def __init__(self, display): """Initiates an eyetracker dummy object, that simulates gaze position using the mouse arguments display -- a pygaze display.Display instance keyword arguments None """ # try to copy docstrings (but ignore it if it fails, as we do # not need it for actual functioning of the code) try: copy_docstr(BaseEyeTracker, Dummy) except: # we're not even going to show a warning, since the copied # docstring is useful for code editors; these load the docs # in a non-verbose manner, so warning messages would be lost pass self.recording = False self.blinking = False self.bbpos = (settings.DISPSIZE[0]/2, settings.DISPSIZE[1]/2) self.resolution = settings.DISPSIZE[:] self.simulator = Mouse(disptype=settings.DISPTYPE, mousebuttonlist=None, timeout=2, visible=False) self.kb = Keyboard(disptype=settings.DISPTYPE, keylist=None, timeout=None) self.angrybeep = Sound(osc='saw',freq=100, length=100, attack=0, decay=0, soundfile=None) self.display = display self.screen = Screen(disptype=settings.DISPTYPE, mousevisible=False)
def confirm_abort_experiment(self):
"""
Asks for confirmation before aborting the experiment. Displays a
confirmation screen, collects the response, and acts accordingly.
Exceptions:
Raises a response_error upon confirmation.
Returns:
False if no confirmation was given.
"""
# Display the confirmation screen
scr = Screen(disptype=DISPTYPE)
kb = Keyboard(timeout=5000)
yc = DISPSIZE[1] / 2
xc = DISPSIZE[0] / 2
ld = 40 # Line height
scr.draw_text(u'Really abort experiment?', pos=(xc, yc - 3 * ld))
scr.draw_text(u'Press \'Y\' to abort', pos=(xc, yc - 0.5 * ld))
scr.draw_text(u'Press any other key or wait 5s to go to setup', \
pos=(xc, yc+0.5*ld))
self.display.fill(scr)
self.display.show()
# process the response:
try:
key, time = kb.get_key()
except:
return False
# if confirmation, close experiment
if key == u'y':
raise Exception(u'The experiment was aborted')
self.eyelink_graphics.esc_pressed = False
return False
def __init__(self, display): """Initiates an eyetracker dummy object, that simulates gaze position using the mouse arguments display -- a pygaze display.Display instance keyword arguments None """ # try to copy docstrings (but ignore it if it fails, as we do # not need it for actual functioning of the code) try: copy_docstr(BaseEyeTracker, Dummy) except: # we're not even going to show a warning, since the copied # docstring is useful for code editors; these load the docs # in a non-verbose manner, so warning messages would be lost pass self.recording = False self.blinking = False self.bbpos = (settings.DISPSIZE[0]/2, settings.DISPSIZE[1]/2) self.resolution = settings.DISPSIZE[:] self.simulator = Mouse(disptype=settings.DISPTYPE, mousebuttonlist=None, timeout=2, visible=False) self.kb = Keyboard(disptype=settings.DISPTYPE, keylist=None, timeout=None) self.angrybeep = Sound(osc='saw',freq=100, length=100, attack=0, decay=0, soundfile=None) self.display = display self.screen = Screen(disptype=settings.DISPTYPE, mousevisible=False)
def __init__(self, display):
"""Initiates a 'dumb dummy' object, that doesn't do a thing
arguments
display -- a pygaze display.Display instance
keyword arguments
None
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docsafe_decode(BaseEyeTracker, DumbDummy)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
self.recording = False
self.blinking = False
self.bbpos = (settings.DISPSIZE[0] / 2, settings.DISPSIZE[1] / 2)
self.display = display
self.screen = Screen(disptype=settings.DISPTYPE, mousevisible=False)
def confirm_abort_experiment(self): """ Asks for confirmation before aborting the experiment. Displays a confirmation screen, collects the response, and acts accordingly. Exceptions: Raises a response_error upon confirmation. Returns: False if no confirmation was given. """ # Display the confirmation screen scr = Screen(disptype=DISPTYPE) kb = Keyboard(timeout=5000) yc = DISPSIZE[1]/2 xc = DISPSIZE[0]/2 ld = 40 # Line height scr.draw_text(u'Really abort experiment?', pos=(xc, yc-3*ld)) scr.draw_text(u'Press \'Y\' to abort', pos=(xc, yc-0.5*ld)) scr.draw_text(u'Press any other key or wait 5s to go to setup', \ pos=(xc, yc+0.5*ld)) self.display.fill(scr) self.display.show() # process the response: try: key, time = kb.get_key() except: return False # if confirmation, close experiment if key == u'y': raise Exception(u'The experiment was aborted') self.eyelink_graphics.esc_pressed = False return False
def draw_menu_screen(self): """ desc: Draws the menu screen. """ self.menuscreen = Screen(disptype=settings.DISPTYPE, mousevisible=False) self.menuscreen.draw_text(text="Eyelink calibration menu", pos=(self.xc,self.yc-6*self.ld), center=True, font='mono', fontsize=int(2*self.fontsize), antialias=True) self.menuscreen.draw_text(text="%s (pygaze %s, pylink %s)" \ % (self.libeyelink.eyelink_model, pygaze.version, pylink.__version__), pos=(self.xc,self.yc-5*self.ld), center=True, font='mono', fontsize=int(.8*self.fontsize), antialias=True) self.menuscreen.draw_text(text="Press C to calibrate", pos=(self.xc, self.yc-3*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text(text="Press V to validate", pos=(self.xc, self.yc-2*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text(text="Press A to auto-threshold", pos=(self.xc,self.yc-1*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text(text="Press I to toggle extra info in camera image", pos=(self.xc,self.yc-0*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text(text="Press Enter to show camera image", pos=(self.xc,self.yc+1*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text( text="(then change between images using the arrow keys)", pos=(self.xc, self.yc+2*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text(text="Press Escape to abort experiment", pos=(self.xc, self.yc+4*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True) self.menuscreen.draw_text(text="Press Q to exit menu", pos=(self.xc, self.yc+5*self.ld), center=True, font='mono', fontsize=self.fontsize, antialias=True)
class SMItracker(BaseEyeTracker):
"""A class for SMI eye tracker objects"""
def __init__(self,
display,
ip='127.0.0.1',
sendport=4444,
receiveport=5555,
logfile=settings.LOGFILE,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
**args):
"""Initializes the SMItracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
ip -- internal ip address for iViewX (default =
'127.0.0.1')
sendport -- port number for iViewX sending (default = 4444)
receiveport -- port number for iViewX receiving (default = 5555)
logfile -- logfile name (string value); note that this is the
name for the SMI logfile, NOT the .idf file
(default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, SMITracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = settings.DISPSIZE # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# output file properties
self.outputfile = logfile
self.description = "experiment" # TODO: EXPERIMENT NAME
self.participant = "participant" # TODO: PP NAME
# eye tracker properties
self.connected = False
self.recording = False
self.eye_used = 0 # 0=left, 1=right, 2=binocular
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.errdist = 2 # degrees; maximal error for drift correction
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# set logger
res = iViewXAPI.iV_SetLogger(c_int(1),
c_char_p(logfile + '_SMILOG.txt'))
if res != 1:
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.__init__: failed to set logger; %s"
% err)
# first logger argument is for logging type (I'm guessing these are decimal bit codes)
# LOG status bitcode
# 1 = LOG_LEVEL_BUG 00001
# 2 = LOG_LEVEL_iV_FCT 00010
# 4 = LOG_LEVEL_ETCOM 00100
# 8 = LOG_LEVEL_ALL 01000
# 16 = LOG_LEVEL_IV_COMMAND 10000
# these can be used together, using a bitwise or, e.g.: 1|2|4 (bitcode 00111)
# connect to iViewX
res = iViewXAPI.iV_Connect(c_char_p(ip), c_int(sendport), c_char_p(ip),
c_int(receiveport))
if res == 1:
res = iViewXAPI.iV_GetSystemInfo(byref(systemData))
self.samplerate = systemData.samplerate
self.sampletime = 1000.0 / self.samplerate
if res != 1:
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.__init__: failed to get system information; %s"
% err)
# handle connection errors
else:
self.connected = False
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.__init__: establishing connection failed; %s"
% err)
# initiation report
self.log("pygaze initiation report start")
self.log("experiment: %s" % self.description)
self.log("participant: %s" % self.participant)
self.log("display resolution: %sx%s" %
(self.dispsize[0], self.dispsize[1]))
self.log("display size in cm: %sx%s" %
(self.screensize[0], self.screensize[1]))
self.log("samplerate: %s Hz" % self.samplerate)
self.log("sampletime: %s ms" % self.sampletime)
self.log("fixation threshold: %s degrees" % self.fixtresh)
self.log("speed threshold: %s degrees/second" % self.spdtresh)
self.log("acceleration threshold: %s degrees/second**2" %
self.accthresh)
self.log("pygaze initiation report end")
def calibrate(self, calibrate=True, validate=True):
"""Calibrates the eye tracking system
arguments
None
keyword arguments
calibrate -- Boolean indicating if calibration should be
performed (default = True)
validate -- Boolean indicating if validation should be performed
(default = True)
returns
success -- returns True if calibration succeeded, or False if
not; in addition a calibration log is added to the
log file and some properties are updated (i.e. the
thresholds for detection algorithms)
"""
# TODO:
# add feedback for calibration (e.g. with iV_GetAccuracyImage (struct ImageStruct * imageData) for accuracy and iV_GetEyeImage for cool eye pictures)
# example: res = iViewXAPI.iV_GetEyeImage(byref(imageData))
# ImageStruct has four data fields:
# imageHeight -- int vertical size (px)
# imageWidth -- int horizontal size (px)
# imageSize -- int image data size (byte)
# imageBuffer -- pointer to image data (I have NO idea what format this is in)
# configure calibration (NOT starting it)
calibrationData = CCalibration(
9, 1, 0, 1, 1, 0, 127, 1, 15, b""
) # (method (i.e.: number of points), visualization, display, speed, auto, fg, bg, shape, size, filename)
# setup calibration
res = iViewXAPI.iV_SetupCalibration(byref(calibrationData))
if res != 1:
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.calibrate: failed to setup calibration; %s"
% err)
# calibrate
cres = iViewXAPI.iV_Calibrate()
# validate if calibration returns succes
if cres == 1:
cerr = None
vres = iViewXAPI.iV_Validate()
# handle validation errors
if vres != 1:
verr = errorstring(vres)
else:
verr = None
## # TEST #
## res = iViewXAPI.iV_GetAccuracyImage(byref(imageData))
## self.log("IMAGEBUFFERSTART")
## self.log(imageData.imageBuffer)
## self.log("IMAGEBUFFERSTOP")
## print("Image height: %s, image width: %s, image size: %s" % (imageData.imageHeight,imageData.imageWidth, imageData.imageSize))
## print imageData.imageBuffer
## ########
# handle calibration errors
else:
cerr = errorstring(cres)
# return succes
if cerr == None:
print("libsmi.SMItracker.calibrate: calibration was succesful")
if verr == None:
print("libsmi.SMItracker.calibrate: validation was succesful")
# present instructions
self.disp.fill() # clear display
self.screen.draw_text(
text=
"Noise calibration: please look at the dot\n\n(press space to start)",
pos=(self.dispsize[0] / 2, int(self.dispsize[1] * 0.2)),
center=True)
self.screen.draw_fixation(fixtype='dot')
self.disp.fill(self.screen)
self.disp.show()
self.screen.clear() # clear screen again
# wait for spacepress
self.kb.get_key(keylist=['space'], timeout=None)
# show fixation
self.disp.fill()
self.screen.draw_fixation(fixtype='dot')
self.disp.fill(self.screen)
self.disp.show()
self.screen.clear()
# wait for a bit, to allow participant to fixate
clock.pause(500)
# get samples
sl = [
self.sample()
] # samplelist, prefilled with 1 sample to prevent sl[-1] from producing an error; first sample will be ignored for RMS calculation
t0 = clock.get_time() # starting time
while clock.get_time() - t0 < 1000:
s = self.sample() # sample
if s != sl[-1] and s != (-1, -1) and s != (0, 0):
sl.append(s)
# calculate RMS noise
Xvar = []
Yvar = []
for i in range(2, len(sl)):
Xvar.append((sl[i][0] - sl[i - 1][0])**2)
Yvar.append((sl[i][1] - sl[i - 1][1])**2)
XRMS = (sum(Xvar) / len(Xvar))**0.5
YRMS = (sum(Yvar) / len(Yvar))**0.5
self.pxdsttresh = (XRMS, YRMS)
# calculate pixels per cm
pixpercm = (self.dispsize[0] / float(self.screensize[0]) +
self.dispsize[1] / float(self.screensize[1])) / 2
# get accuracy
res = 0
i = 0
while res != 1 and i < self.maxtries: # multiple tries, in case no (valid) sample is available
res = iViewXAPI.iV_GetAccuracy(
byref(accuracyData), 0) # 0 is for 'no visualization'
i += 1
clock.pause(int(self.sampletime)) # wait for sampletime
if res == 1:
self.accuracy = (
(accuracyData.deviationLX, accuracyData.deviationLY),
(accuracyData.deviationLX, accuracyData.deviationLY)
) # dsttresh = (left tuple, right tuple); tuple = (horizontal deviation, vertical deviation) in degrees of visual angle
else:
err = errorstring(res)
print(
"WARNING libsmi.SMItracker.calibrate: failed to obtain accuracy data; %s"
% err)
self.accuracy = ((2, 2), (2, 2))
print(
"libsmi.SMItracker.calibrate: As an estimate, the intersample distance threshhold was set to it's default value of 2 degrees"
)
# get distance from screen to eyes (information from tracker)
res = 0
i = 0
while res != 1 and i < self.maxtries: # multiple tries, in case no (valid) sample is available
res = iViewXAPI.iV_GetSample(byref(sampleData))
i += 1
clock.pause(int(self.sampletime)) # wait for sampletime
if res == 1:
screendist = sampleData.leftEye.eyePositionZ / 10.0 # eyePositionZ is in mm; screendist is in cm
else:
err = errorstring(res)
print(
"WARNING libsmi.SMItracker.calibrate: failed to obtain screen distance; %s"
% err)
screendist = settings.SCREENDIST
print(
"libsmi.SMItracker.calibrate: As an estimate, the screendistance was set to it's default value of 57 cm"
)
# calculate thresholds based on tracker settings
self.pxerrdist = deg2pix(screendist, self.errdist, pixpercm)
self.pxfixtresh = deg2pix(screendist, self.fixtresh, pixpercm)
self.pxaccuracy = ((deg2pix(screendist, self.accuracy[0][0],
pixpercm),
deg2pix(screendist, self.accuracy[0][1],
pixpercm)),
(deg2pix(screendist, self.accuracy[1][0],
pixpercm),
deg2pix(screendist, self.accuracy[1][1],
pixpercm)))
self.pxspdtresh = deg2pix(
screendist, self.spdtresh / 1000.0,
pixpercm) # in pixels per millisecond
self.pxacctresh = deg2pix(
screendist, self.accthresh / 1000.0,
pixpercm) # in pixels per millisecond**2
# calibration report
self.log("pygaze calibration report start")
self.log("accuracy (degrees): LX=%s, LY=%s, RX=%s, RY=%s" %
(self.accuracy[0][0], self.accuracy[0][1],
self.accuracy[1][0], self.accuracy[1][1]))
self.log("accuracy (in pixels): LX=%s, LY=%s, RX=%s, RY=%s" %
(self.pxaccuracy[0][0], self.pxaccuracy[0][1],
self.pxaccuracy[1][0], self.pxaccuracy[1][1]))
self.log("precision (RMS noise in pixels): X=%s, Y=%s" %
(self.pxdsttresh[0], self.pxdsttresh[1]))
self.log("distance between participant and display: %s cm" %
screendist)
self.log("fixation threshold: %s pixels" % self.pxfixtresh)
self.log("speed threshold: %s pixels/ms" % self.pxspdtresh)
self.log("acceleration threshold: %s pixels/ms**2" %
self.pxacctresh)
self.log("pygaze calibration report end")
return True
# validation error
else:
print(
"WARNING libsmi.SMItracker.calibrate: validation was unsuccesful %s"
% verr)
return False
# calibration error
else:
print(
"WARNING libsmi.SMItracker.calibrate: calibration was unsuccesful; %s"
% cerr)
return False
def close(self):
"""Neatly close connection to tracker
arguments
None
returns
Nothing -- saves data and sets self.connected to False
"""
# save data
res = iViewXAPI.iV_SaveData(str(self.outputfile),
str(self.description),
str(self.participant), 1)
if res != 1:
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.close: failed to save data; %s" %
err)
# close connection
iViewXAPI.iV_Disconnect()
self.connected = False
def connected(self):
"""Checks if the tracker is connected
arguments
None
returns
connected -- True if connection is established, False if not;
sets self.connected to the same value
"""
res = iViewXAPI.iV_IsConnected()
if res == 1:
self.connected = True
else:
self.connected = False
return self.connected
def drift_correction(self, pos=None, fix_triggered=False):
"""Performs a drift check
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
fix_triggered -- Boolean indicating if drift check should be
performed based on gaze position (fix_triggered
= True) or on spacepress (fix_triggered =
False) (default = False)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
pressed = False
while not pressed:
pressed, presstime = self.kb.get_key()
if pressed:
if pressed == 'escape' or pressed == 'q':
print(
"libsmi.SMItracker.drift_correction: 'q' or 'escape' pressed"
)
return self.calibrate(calibrate=True, validate=True)
gazepos = self.sample()
if ((gazepos[0] - pos[0])**2 +
(gazepos[1] - pos[1])**2)**0.5 < self.pxerrdist:
return True
else:
self.errorbeep.play()
return False
def fix_triggered_drift_correction(self,
pos=None,
min_samples=10,
max_dev=60,
reset_threshold=30):
"""Performs a fixation triggered drift correction by collecting
a number of samples and calculating the average distance from the
fixation position
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
min_samples -- minimal amount of samples after which an
average deviation is calculated (default = 10)
max_dev -- maximal deviation from fixation in pixels
(default = 60)
reset_threshold -- if the horizontal or vertical distance in
pixels between two consecutive samples is
larger than this threshold, the sample
collection is reset (default = 30)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key()[0] in ['escape', 'q']:
print(
"libsmi.SMItracker.fix_triggered_drift_correction: 'q' or 'escape' pressed"
)
return self.calibrate(calibrate=True, validate=True)
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold
or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0])**2 + (avg_y - pos[1])**2)**0.5
if d < max_dev:
return True
else:
lx = []
ly = []
def get_eyetracker_clock_async(self):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def log(self, msg):
"""Writes a message to the log file
arguments
ms -- a string to include in the log file
returns
Nothing -- uses native log function of iViewX to include a line
in the log file
"""
res = iViewXAPI.iV_Log(c_char_p(msg))
if res != 1:
err = errorstring(res)
print(
"WARNING libsmi.SMItracker.log: failed to log message '%s'; %s"
% (msg, err))
def log_var(self, var, val):
"""Writes a variable to the log file
arguments
var -- variable name
val -- variable value
returns
Nothing -- uses native log function of iViewX to include a line
in the log file in a "var NAME VALUE" layout
"""
msg = "var %s %s" % (var, val)
res = iViewXAPI.iV_Log(c_char_p(msg))
if res != 1:
err = errorstring(res)
print(
"WARNING libsmi.SMItracker.log_var: failed to log variable '%s' with value '%s'; %s"
% (var, val, err))
def prepare_backdrop(self):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def prepare_drift_correction(self, pos):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def pupil_size(self):
"""Return pupil size
arguments
None
returns
pupil size -- returns pupil diameter for the eye that is currently
being tracked (as specified by self.eye_used) or -1
when no data is obtainable
"""
res = iViewXAPI.iV_GetSample(byref(sampleData))
# if a new sample exists
if res == 1:
# left eye
if self.eye_used == self.left_eye:
ps = sampleData.leftEye.diam
# right eye
else:
ps = sampleData.rightEye.diam
# set prvious pupil size to newest pupil size
self.prevps = ps
return ps
# no new sample available
elif res == 2:
return self.prevps
# invalid data
else:
# print warning to interpreter
err = errorstring(res)
print(
"WARNING libsmi.SMItracker.pupil_size: failed to obtain sample; %s"
% err)
return -1
def sample(self):
"""Returns newest available gaze position
arguments
None
returns
sample -- an (x,y) tuple or a (-1,-1) on an error
"""
res = iViewXAPI.iV_GetSample(byref(sampleData))
if self.eye_used == self.right_eye:
newsample = sampleData.rightEye.gazeX, sampleData.rightEye.gazeY
else:
newsample = sampleData.leftEye.gazeX, sampleData.leftEye.gazeY
if res == 1:
self.prevsample = newsample[:]
return newsample
elif res == 2:
return self.prevsample
else:
err = errorstring(res)
print(
"WARNING libsmi.SMItracker.sample: failed to obtain sample; %s"
% err)
return (-1, -1)
def send_command(self, cmd):
"""Sends a command to the eye tracker
arguments
cmd -- the command (a string value) to be sent to iViewX
returns
Nothing
"""
try:
iViewXAPI.iV_SendCommand(c_char_p(cmd))
except:
raise Exception(
"Error in libsmi.SMItracker.send_command: failed to send remote command to iViewX (iV_SendCommand might be deprecated)"
)
def set_backdrop(self):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def set_eye_used(self):
"""Logs the eye_used variable, based on which eye was specified
(if both eyes are being tracked, the left eye is used)
arguments
None
returns
Nothing -- logs which eye is used by calling self.log_var, e.g.
self.log_var("eye_used", "right")
"""
if self.eye_used == self.right_eye:
self.log_var("eye_used", "right")
else:
self.log_var("eye_used", "left")
def start_recording(self):
"""Starts recording eye position
arguments
None
returns
Nothing -- sets self.recording to True when recording is
successfully started
"""
res = 0
i = 0
while res != 1 and i < self.maxtries:
res = iViewXAPI.iV_StartRecording()
i += 1
if res == 1:
self.recording = True
else:
self.recording = False
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.start_recording: %s" %
err)
def status_msg(self, msg):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def stop_recording(self):
"""Stop recording eye position
arguments
None
returns
Nothing -- sets self.recording to False when recording is
successfully started
"""
res = 0
i = 0
while res != 1 and i < self.maxtries:
res = iViewXAPI.iV_StopRecording()
i += 1
if res == 1:
self.recording = False
else:
self.recording = False
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.stop_recording: %s" %
err)
def set_detection_type(self, eventdetection):
"""Set the event detection type to either PyGaze algorithms, or
native algorithms as provided by the manufacturer (only if
available: detection type will default to PyGaze if no native
functions are available)
arguments
eventdetection -- a string indicating which detection type
should be employed: either 'pygaze' for
PyGaze event detection algorithms or
'native' for manufacturers algorithms (only
if available; will default to 'pygaze' if no
native event detection is available)
returns -- detection type for saccades, fixations and
blinks in a tuple, e.g.
('pygaze','native','native') when 'native'
was passed, but native detection was not
available for saccade detection
"""
if eventdetection in ['pygaze', 'native']:
self.eventdetection = eventdetection
return ('pygaze', 'native', 'pygaze')
def wait_for_event(self, event):
"""Waits for event
arguments
event -- an integer event code, one of the following:
3 = STARTBLINK
4 = ENDBLINK
5 = STARTSACC
6 = ENDSACC
7 = STARTFIX
8 = ENDFIX
returns
outcome -- a self.wait_for_* method is called, depending on the
specified event; the return values of corresponding
method are returned
"""
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
"Error in libsmi.SMItracker.wait_for_event: eventcode %s is not supported"
% event)
return outcome
def wait_for_blink_end(self):
"""Waits for a blink end and returns the blink ending time
arguments
None
returns
timestamp -- blink ending time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def wait_for_blink_start(self):
"""Waits for a blink start and returns the blink starting time
arguments
None
returns
timestamp -- blink starting time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed 150 ms
if clock.get_time() - t0 >= 150:
# return timestamp of blink start
return t0
def wait_for_fixation_end(self):
"""Returns time and gaze position when a fixation has ended;
function assumes that a 'fixation' has ended when a deviation of
more than self.pxfixtresh from the initial fixation position has
been detected (self.pxfixtresh is created in self.calibration,
based on self.fixtresh, a property defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
moving = True
while moving:
# get newest event
res = 0
while res != 1:
res = iViewXAPI.iV_GetEvent(byref(eventData))
stime = clock.get_time()
# check if event is a fixation (SMI only supports
# fixations at the moment)
if eventData.eventType == 'F':
# get timestamp and starting position
timediff = stime - (int(eventData.startTime) / 1000.0)
etime = timediff + (int(eventData.endTime) / 1000.0
) # time is in microseconds
fixpos = (evenData.positionX, evenData.positionY)
# return starting time and position
return etime, fixpos
# # # # #
# PyGaze method
else:
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0] - spos[0])**2 + (
npos[1] -
spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_fixation_start(self):
"""Returns starting time and position when a fixation is started;
function assumes a 'fixation' has started when gaze position
remains reasonably stable (i.e. when most deviant samples are
within self.pxfixtresh) for five samples in a row (self.pxfixtresh
is created in self.calibration, based on self.fixtresh, a property
defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a fixation start
# detection built into their API (only ending)
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer fixation START detection (only \
fixation ENDING; PyGaze algorithm will be used")
# # # # #
# PyGaze method
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0] - spos[0])**2 + (
npos[1] -
spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a saccade is
ended; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos, endpos -- endtime in milliseconds (from
expbegintime); startpos and endpos
are (x,y) gaze position tuples
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0] - spos[0])**2 + (prevpos[1] - spos[1])**
2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1 - t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0] - prevpos[0])**2 + (newpos[1] - prevpos[1])**
2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (
t1 - t0
) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1 * self.pxacctresh
and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a saccade is
started; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos -- endtime in milliseconds (from expbegintime);
startpos is an (x,y) gaze position tuple
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0] - prevpos[0]
sy = newpos[1] - prevpos[1]
if (sx / self.pxdsttresh[0])**2 + (
sy / self.pxdsttresh[1]
)**2 > self.weightdist: # weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**
2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def is_valid_sample(self, gazepos):
"""Checks if the sample provided is valid, based on SMI specific
criteria (for internal use)
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (-1, -1):
return False
# sometimes, on SMI devices, invalid samples can actually contain
# numbers; these do
elif sum(gazepos) < 10 and 0.0 in gazepos:
return False
# in any other case, the sample is valid
return True
class libeyelink(BaseEyeTracker):
MAX_TRY = 100
def __init__(self,
display,
resolution=DISPSIZE,
data_file=LOGFILENAME + ".edf",
fg_color=FGC,
bg_color=BGC,
eventdetection=EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
force_drift_correct=True,
pupil_size_mode=EYELINKPUPILSIZEMODE,
**args):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# try to import copy docstring (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, libeyelink)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
global _eyelink
# Make sure that we have a valid data file. The local_data_file may
# contain a folder. The eyelink_data_file is only a basename, i.e.
# without folder. The eyelink_data_file must be at most eight characters
# and end with a `.edf` extension.
self.local_data_file = data_file
self.eyelink_data_file = os.path.basename(data_file)
stem, ext = os.path.splitext(self.eyelink_data_file)
if len(stem) > 8 or ext.lower() != '.edf':
raise Exception(
"The EyeLink cannot handle filenames longer than eight "
"characters (excluding '.edf' extension).")
# properties
self.display = display
self.fontsize = 18
self.scr = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=["escape", "q"], timeout=1)
self.resolution = resolution
self.recording = False
self.saccade_velocity_treshold = saccade_velocity_threshold
self.saccade_acceleration_treshold = saccade_acceleration_threshold
self.eye_used = None
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.pupil_size_mode = pupil_size_mode
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
# degrees; maximal distance from fixation start (if gaze wanders beyond
# this, fixation has stopped)
self.fixtresh = 1.5
# milliseconds; amount of time gaze has to linger within self.fixtresh
# to be marked as a fixation
self.fixtimetresh = 100
# degrees per second; saccade velocity threshold
self.spdtresh = self.saccade_velocity_treshold
# degrees per second**2; saccade acceleration threshold
self.accthresh = self.saccade_acceleration_treshold
self.set_detection_type(eventdetection)
# weighted distance, used for determining whether a movement is due to
# measurement error (1 is ok, higher is more conservative and will
# result in only larger saccades to be detected)
self.weightdist = 10
# distance between participant and screen in cm
self.screendist = SCREENDIST
# distance between participant and screen in cm
self.screensize = SCREENSIZE
self.pixpercm = (self.resolution[0]/float(self.screensize[0]) + \
self.resolution[1]/float(self.screensize[1])) / 2.0
# only initialize eyelink once
if _eyelink == None:
try:
_eyelink = pylink.EyeLink()
except:
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to "
"connect to the tracker!")
# determine software version of tracker
self.tracker_software_ver = 0
self.eyelink_ver = pylink.getEYELINK().getTrackerVersion()
if self.eyelink_ver == 3:
tvstr = pylink.getEYELINK().getTrackerVersionString()
vindex = tvstr.find("EYELINK CL")
self.tracker_software_ver = int(float(tvstr[(vindex + \
len("EYELINK CL")):].strip()))
if self.eyelink_ver == 1:
self.eyelink_model = 'EyeLink I'
elif self.eyelink_ver == 2:
self.eyelink_model = 'EyeLink II'
elif self.eyelink_ver == 3:
self.eyelink_model = 'EyeLink 1000'
else:
self.eyelink_model = 'EyeLink (model unknown)'
# Open graphics
self.eyelink_graphics = EyelinkGraphics(self, _eyelink)
pylink.openGraphicsEx(self.eyelink_graphics)
# Optionally force drift correction. For some reason this must be done
# as (one of) the first things, otherwise a segmentation fault occurs.
if force_drift_correct:
self.send_command('driftcorrect_cr_disable = OFF')
# Set pupil-size mode
if self.pupil_size_mode == 'area':
pylink.getEYELINK().setPupilSizeDiameter(False)
elif self.pupil_size_mode == 'diameter':
pylink.getEYELINK().setPupilSizeDiameter(True)
else:
raise Exception(
"pupil_size_mode should be 'area' or 'diameter', not %s" \
% self.pupil_size_mode)
pylink.getEYELINK().openDataFile(self.eyelink_data_file)
pylink.flushGetkeyQueue()
pylink.getEYELINK().setOfflineMode()
# notify eyelink of display resolution
self.send_command("screen_pixel_coords = 0 0 %d %d" % \
(self.resolution[0], self.resolution[1]))
# get some configuration stuff
if self.eyelink_ver >= 2:
self.send_command("select_parser_configuration 0")
if self.eyelink_ver == 2: # turn off scenelink camera stuff
self.send_command("scene_camera_gazemap = NO")
# set EDF file contents (this specifies which data is written to the EDF
# file)
self.send_command(
"file_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,MESSAGE,BUTTON"
)
if self.tracker_software_ver >= 4:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS,HTARGET"
)
else:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS")
# set link data (this specifies which data is sent through the link and
# thus can be used in gaze contingent displays)
self.send_command(
"link_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,BUTTON")
if self.tracker_software_ver >= 4:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS,HTARGET"
)
else:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS")
# not quite sure what this means (according to Sebastiaan Mathot, it
# might be the button that is used to end drift correction?)
self.send_command("button_function 5 'accept_target_fixation'")
if not self.connected():
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to connect "
"to the eyetracker!")
def send_command(self, cmd):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
pylink.getEYELINK().sendCommand(cmd)
def log(self, msg):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
pylink.getEYELINK().sendMessage(msg)
def log_var(self, var, val):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
pylink.getEYELINK().sendMessage("var %s %s" % (var, val))
def status_msg(self, msg):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
print('status message: %s' % msg)
pylink.getEYELINK().sendCommand("record_status_message '%s'" % msg)
def connected(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
return pylink.getEYELINK().isConnected()
def calibrate(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if self.recording:
raise Exception(
"Error in libeyelink.libeyelink.calibrate(): Trying to "
"calibrate after recording has started!")
# # # # #
# EyeLink calibration and validation
# attempt calibrate; confirm abort when esc pressed
while True:
self.eyelink_graphics.esc_pressed = False
pylink.getEYELINK().doTrackerSetup()
if not self.eyelink_graphics.esc_pressed:
break
self.confirm_abort_experiment()
# If we are using the built-in EyeLink event detection, we don't need
# the RMS calibration routine.
if self.eventdetection == 'native':
return
# # # # #
# RMS calibration
# present instructions
self.display.fill() # clear display
self.scr.draw_text(text= \
"Noise calibration: please look at the dot\n\n(press space to start)",
pos=(self.resolution[0]/2, int(self.resolution[1]*0.2)),
center=True, fontsize=self.fontsize)
self.scr.draw_fixation(fixtype='dot')
self.display.fill(self.scr)
self.display.show()
self.scr.clear() # clear screen again
# wait for spacepress
self.kb.get_key(keylist=['space'], timeout=None)
# start recording
self.log("PYGAZE RMS CALIBRATION START")
self.start_recording()
# show fixation
self.display.fill()
self.scr.draw_fixation(fixtype='dot')
self.display.fill(self.scr)
self.display.show()
self.scr.clear()
# wait for a bit, to allow participant to fixate
clock.pause(500)
# get samples
# samplelist, prefilled with 1 sample to prevent sl[-1] from producing
# an error; first sample will be ignored for RMS calculation
sl = [self.sample()]
t0 = clock.get_time() # starting time
while clock.get_time() - t0 < 1000:
s = self.sample() # sample
if s != sl[-1] and s != (-1, -1) and s != (0, 0):
sl.append(s)
# stop recording
self.log("PYGAZE RMS CALIBRATION END")
self.stop_recording()
# calculate RMS noise
Xvar = []
Yvar = []
for i in range(2, len(sl)):
Xvar.append((sl[i][0] - sl[i - 1][0])**2)
Yvar.append((sl[i][1] - sl[i - 1][1])**2)
XRMS = (sum(Xvar) / len(Xvar))**0.5
YRMS = (sum(Yvar) / len(Yvar))**0.5
self.pxdsttresh = (XRMS, YRMS)
# recalculate thresholds (degrees to pixels)
self.pxfixtresh = deg2pix(self.screendist, self.fixtresh,
self.pixpercm)
self.pxspdtresh = deg2pix(
self.screendist, self.spdtresh,
self.pixpercm) / 1000.0 # in pixels per millisecons
self.pxacctresh = deg2pix(
self.screendist, self.accthresh,
self.pixpercm) / 1000.0 # in pixels per millisecond**2
def drift_correction(self, pos=None, fix_triggered=False):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if self.recording:
raise Exception(
"Error in libeyelink.libeyelink.drift_correction(): Trying to "
"perform drift correction after recording has started!")
if not self.connected():
raise Exception(
"Error in libeyelink.libeyelink.drift_correction(): The "
"eyelink is not connected!")
if pos == None:
pos = self.resolution[0] / 2, self.resolution[1] / 2
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
return self.manual_drift_correction(pos)
def manual_drift_correction(self, pos):
"""
Performs a manual, i.e. spacebar-triggered drift correction.
Arguments:
pos -- The positionf or the drift-correction target.
Returns:
True if drift correction was successfull, False otherwise.
"""
self.draw_drift_correction_target(pos[0], pos[1])
self.eyelink_graphics.esc_pressed = False
try:
# The 0 parameters indicate that the display should not be cleared
# and we should not be allowed to fall back to the set-up screen.
error = pylink.getEYELINK().doDriftCorrect(pos[0], pos[1], 0, 0)
except:
error = -1
# A 0 exit code means successful drift correction
if error == 0:
return True
# If escape was pressed, we present the confirm abort screen
if self.eyelink_graphics.esc_pressed:
self.confirm_abort_experiment()
# If 'q' was pressed, we drop back to the calibration screen
else:
self.calibrate()
return False
def prepare_drift_correction(self, pos):
"""Puts the tracker in drift correction mode"""
# start collecting samples in drift correction mode
self.send_command("heuristic_filter = ON")
self.send_command("drift_correction_targets = %d %d" % pos)
self.send_command("start_drift_correction data = 0 0 1 0")
pylink.msecDelay(50)
# wait for a bit until samples start coming in (again, not sure if this
# is indeed what's going on)
if not pylink.getEYELINK().waitForBlockStart(100, 1, 0):
print(
"WARNING libeyelink.libeyelink.prepare_drift_correction(): "
"Failed to perform drift correction (waitForBlockStart error)")
def fix_triggered_drift_correction(self,
pos=None,
min_samples=30,
max_dev=60,
reset_threshold=10):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if self.recording:
raise Exception(
"Error in libeyelink.libeyelink.fix_triggered_drift_correction(): "
"Trying to perform drift correction after recording has started!"
)
self.recording = True
if pos == None:
pos = self.resolution[0] / 2, self.resolution[1] / 2
self.prepare_drift_correction(pos)
self.draw_drift_correction_target(pos[0], pos[1])
# loop until we have enough samples
lx = []
ly = []
while len(lx) < min_samples:
# Check whether the EyeLink is put into set-up mode on the EyeLink
# PC and, if so, jump to the calibration menu.
if pylink.getEYELINK().getCurrentMode() == pylink.IN_SETUP_MODE:
self.recording = False
self.calibrate()
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"'q' pressed")
return False
# pressing escape enters the calibration screen
resp = self.kb.get_key(keylist=["escape", "q"], timeout=1)[0]
if resp == 'escape':
self.recording = False
self.confirm_abort_experiment()
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"'escape' pressed")
return False
elif resp == 'q':
self.recording = False
self.calibrate()
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"'q' pressed")
return False
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample,
# start from scratch.
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold or \
abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# Collect a sample
else:
lx.append(x)
ly.append(y)
# If we have enough samples to perform a drift correction ...
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0])**2 + (avg_y - pos[1])**2)**0.5
# emulate spacebar press on succes
pylink.getEYELINK().sendKeybutton(32, 0, pylink.KB_PRESS)
# getCalibrationResult() returns 0 on success and an exception
# or a non-zero value otherwise
result = -1
try:
result = pylink.getEYELINK().getCalibrationResult()
except:
lx = []
ly = []
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"try again")
if result != 0:
try:
result = pylink.getEYELINK().getCalibrationResult()
except:
lx = []
ly = []
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"try again")
# apply drift correction
pylink.getEYELINK().applyDriftCorrect()
self.recording = False
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): success")
return True
def start_recording(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.recording = True
i = 0
while True:
# params: write samples, write event, send samples, send events
print(u'starting recording ...')
error = pylink.getEYELINK().startRecording(1, 1, 1, 1)
print(u'returned %s' % error)
if not error:
break
if i > self.MAX_TRY:
raise Exception(
"Error in libeyelink.libeyelink.start_recording(): Failed "
"to start recording!")
self.close()
clock.expend()
i += 1
print(
("WARNING libeyelink.libeyelink.start_recording(): Failed to "
"start recording (attempt %d of %d)") % (i, self.MAX_TRY))
pylink.msecDelay(100)
# don't know what this is
print(u'Start realtime mode ...')
pylink.msecDelay(100)
pylink.beginRealTimeMode(100)
# wait a bit until samples start coming in
print(u'Wait for block start ...')
pylink.msecDelay(100)
if not pylink.getEYELINK().waitForBlockStart(100, 1, 0):
raise Exception(
"Error in libeyelink.libeyelink.start_recording(): Failed to "
"start recording (waitForBlockStart error)!")
print(u'done ...')
def stop_recording(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
print(u'stopping recording ...')
self.recording = False
pylink.endRealTimeMode()
pylink.getEYELINK().setOfflineMode()
pylink.msecDelay(500)
print(u'done ...')
def close(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.eyelink_graphics.close()
if self.recording:
self.stop_recording()
# close data file and transfer it to the experimental PC
print("libeyelink.libeyelink.close(): Closing data file")
pylink.getEYELINK().closeDataFile()
pylink.msecDelay(500)
print("libeyelink.libeyelink.close(): Transferring %s to %s" \
% (self.eyelink_data_file, self.local_data_file))
pylink.getEYELINK().receiveDataFile(self.eyelink_data_file,
self.local_data_file)
pylink.msecDelay(500)
print("libeyelink.libeyelink.close(): Closing eyelink")
pylink.getEYELINK().close()
pylink.msecDelay(500)
def set_eye_used(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.eye_used = pylink.getEYELINK().eyeAvailable()
if self.eye_used == self.right_eye:
self.log_var("eye_used", "right")
elif self.eye_used == self.left_eye or self.eye_used == self.binocular:
self.log_var("eye_used", "left")
self.eye_used = self.left_eye
else:
print("WARNING libeyelink.libeyelink.set_eye_used(): Failed to "
"determine which eye is being recorded")
def pupil_size(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.pupil_size(): Recording was "
"not started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
# get newest sample
s = pylink.getEYELINK().getNewestSample()
# check if sample is new
if s != None:
# right eye
if self.eye_used == self.right_eye and s.isRightSample():
ps = s.getRightEye().getPupilSize()
# left eye
elif self.eye_used == self.left_eye and s.isLeftSample():
ps = s.getLeftEye().getPupilSize()
# invalid
else:
ps = -1
# set new pupil size as previous pupil size
self.prevps = ps
# if no new sample is available, use old data
else:
ps = self.prevps
return ps
def sample(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.sample(): Recording was not "
"started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
s = pylink.getEYELINK().getNewestSample()
if s != None:
if self.eye_used == self.right_eye and s.isRightSample():
gaze = s.getRightEye().getGaze()
elif self.eye_used == self.left_eye and s.isLeftSample():
gaze = s.getLeftEye().getGaze()
else:
gaze = (-1, -1)
self.prevsample = gaze[:]
else:
gaze = self.prevsample[:]
return gaze
def set_detection_type(self, eventdetection):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if eventdetection in ['pygaze', 'native']:
self.eventdetection = eventdetection
return (self.eventdetection, self.eventdetection, self.eventdetection)
def _get_eyelink_clock_async(self):
"""
Retrieve time differenece between tracker timestamps and
current clock time upheld in the pygaze environment.
Note that this is not guaranteed to be a static time difference, the
clocks might run at different speeds. Therefore you should consider
running this function every time you utilize on this time difference.
Returns:
The tracker time minus the clock time
"""
return pylink.getEYELINK().trackerTime() - clock.time()
def wait_for_event(self, event):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.wait_for_event(): Recording "
"was not started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
if self.eventdetection == 'native':
# since the link buffer was not have been polled, old data has
# accumulated in the buffer -- so ignore events that are old:
t0 = clock.time() # time of call
while True:
d = pylink.getEYELINK().getNextData()
if d == event:
float_data = pylink.getEYELINK().getFloatData()
# corresponding clock_time
tc = float_data.getTime() - self._get_eyelink_clock_async()
if tc > t0:
return tc, float_data
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
("Error in libeyelink.libeyelink.wait_for_event: eventcode %s "
"is not supported") % event)
return outcome
def wait_for_saccade_start(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.STARTSACC)
return t, d.getStartGaze()
# # # # #
# PyGaze method
else:
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0] - prevpos[0]
sy = newpos[1] - prevpos[1]
# weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means
# movement larger than RMS noise
if (sx/self.pxdsttresh[0])**2 + (sy/self.pxdsttresh[1])**2 \
> self.weightdist:
# calculate distance
# intersampledistance = speed in pixels/ms
s = ((sx)**2 + (sy)**2)**0.5
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0
) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above
# threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def wait_for_saccade_end(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.ENDSACC)
return t, d.getStartGaze(), d.getEndGaze()
# # # # #
# PyGaze method
else:
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
# = intersample distance = speed in px/sample
s = ((prevpos[0] - spos[0])**2 + (prevpos[1] - spos[1])**2)**0.5
v0 = s / (t1 - t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
# = speed in pixels/sample
s = ((newpos[0]-prevpos[0])**2 + \
(newpos[1]-prevpos[1])**2)**0.5
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
# acceleration in pixels/sample**2 (actually is
# v1-v0 / t1-t0; but t1-t0 = 1 sample)
a = (v1 - v0) / (t1 - t0)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1*self.pxacctresh and \
a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_fixation_start(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.STARTFIX)
return t, d.getTime(), d.getStartGaze()
# # # # #
# PyGaze method
else:
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > \
self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_fixation_end(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.ENDFIX)
return t, d.getTime(), d.getStartGaze()
# # # # #
# PyGaze method
else:
# function assumes that a 'fixation' has ended when a deviation of
# more than fixtresh from the initial 'fixation' position has been
# detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > \
self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_blink_start(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.STARTBLINK)
return t, d.getTime()
# # # # #
# PyGaze method
else:
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed 150 ms
if clock.get_time() - t0 >= 150:
# return timestamp of blink start
return t0
def wait_for_blink_end(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.ENDBLINK)
return t
# # # # #
# PyGaze method
else:
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def set_draw_calibration_target_func(self, func):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.eyelink_graphics.draw_cal_target = func
# ***
#
# Internal functions below
#
# ***
def is_valid_sample(self, gazepos):
"""
Checks if the sample provided is valid, based on EyeLink specific
criteria.
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (-1, -1):
return False
# in any other case, the sample is valid
return True
def confirm_abort_experiment(self):
"""
Asks for confirmation before aborting the experiment. Displays a
confirmation screen, collects the response, and acts accordingly.
Exceptions:
Raises a response_error upon confirmation.
Returns:
False if no confirmation was given.
"""
# Display the confirmation screen
scr = Screen(disptype=DISPTYPE)
kb = Keyboard(timeout=5000)
yc = DISPSIZE[1] / 2
xc = DISPSIZE[0] / 2
ld = 40 # Line height
scr.draw_text(
u'Really abort experiment?',
pos=(xc, yc - 3 * ld),
fontsize=self.fontsize)
scr.draw_text(
u'Press \'Y\' to abort',
pos=(xc, yc - 0.5 * ld),
fontsize=self.fontsize)
scr.draw_text(
u'Press any other key or wait 5s to go to setup',
pos=(xc, yc + 0.5 * ld),
fontsize=self.fontsize)
self.display.fill(scr)
self.display.show()
# process the response:
try:
key, time = kb.get_key()
except:
return False
# if confirmation, close experiment
if key == u'y':
raise Exception(u'The experiment was aborted')
self.eyelink_graphics.esc_pressed = False
return False
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.scr.clear()
self.scr.draw_fixation(fixtype='dot', colour=FGC, pos=(x,y), pw=0, \
diameter=12)
self.display.fill(self.scr)
self.display.show()
# # # # # # directory stuff DIR = os.path.split(os.path.abspath(__file__))[0] soundfile = os.path.join(DIR, 'bark.ogg') imagefile = os.path.join(DIR, 'kitten.png') # # # # # # create instances # initialize the display disp = Display() # initialize a screen scr = Screen() # initialize an EyeTracker tracker = EyeTracker(disp) # initialize a keyboard kb = Keyboard(keylist=['space'], timeout=None) # initialize a sound snd = Sound(soundfile=soundfile) # initialize a Timer timer = Time() # create a new logfile log = Logfile(filename="test")
from pygaze.logfile import Logfile
from pygaze.eyetracker import EyeTracker
import pygaze.libtime as timer
from scansync.mri import MRITriggerBox
##############
# INITIALISE #
##############
# Initialise a new Display instance.
disp = Display()
# Present a start-up screen.
scr = Screen()
scr.draw_text("Loading, please wait...", fontsize=24)
disp.fill(scr)
disp.show()
# Open a new log file.
log = Logfile()
# TODO: Write header.
log.write(["trialnr", "block", "run","stim", "keypress", "go_nogo", "face_onset", "signal_onset","resp_onset", "RT", "accuracy", "respmap", "block_type"])
# Open a new log file to log events.
event_log = Logfile(filename=EVENT_LOG)
event_log.write(["time", "event"])
# Initialise the eye tracker.
tracker = EyeTracker(disp)
class EyelinkGraphics(custom_display):
"""
Implements the EyeLink graphics that are shown on the experimental PC, such
as the camera image, and the calibration dots. This class only implements
the drawing operations, and little to no of the logic behind the set-up,
which is implemented in PyLink.
"""
def __init__(self, display, tracker):
"""
Constructor.
Arguments:
display -- A PyGaze Display object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.display = display
self.screen = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=1)
if DISPTYPE == 'pygame':
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
#if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), \
'__eyelink__.jpg')
# drawing properties
self.xc = self.display.dispsize[0]/2
self.yc = self.display.dispsize[1]/2
self.ld = 40 # line distance
# menu
self.menuscreen = Screen(disptype=DISPTYPE, mousevisible=False)
self.menuscreen.draw_text(text="== Eyelink calibration menu ==", pos= \
(self.xc,self.yc-5*self.ld), center=True, font='mono', fontsize= \
12, antialias=True)
self.menuscreen.draw_text(text="Press C to calibrate", pos=(self.xc, \
self.yc-3*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press V to validate", pos=(self.xc, \
self.yc-2*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press A to auto-threshold", pos=( \
self.xc,self.yc-1*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press Enter to show camera image", \
pos=(self.xc,self.yc+1*self.ld), center=True, font='mono', \
fontsize=12, antialias=True)
self.menuscreen.draw_text(text= \
"(then change between images using the arrow keys)", pos=(self.xc, \
self.yc+2*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press Q to exit menu", pos=(self.xc, \
self.yc+5*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
# beeps
self.__target_beep__ = Sound(osc='sine', freq=440, length=50, attack= \
0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc='sine', freq=880, length=200, \
attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc='sine', freq=220, length=200, \
attack=0, decay=0, soundfile=None)
# further properties
self.state = None
self.imagebuffer = array.array('l')
self.pal = None
self.size = (0,0)
self.set_tracker(tracker)
self.last_mouse_state = -1
def set_tracker(self, tracker):
"""
Connects the tracker to the graphics environment.
Arguments:
tracker -- An tracker object as returned by pylink.EyeLink().
"""
self.tracker = tracker
self.tracker_version = tracker.getTrackerVersion()
if self.tracker_version >= 3:
self.tracker.sendCommand("enable_search_limits=YES")
self.tracker.sendCommand("track_search_limits=YES")
self.tracker.sendCommand("autothreshold_click=YES")
self.tracker.sendCommand("autothreshold_repeat=YES")
self.tracker.sendCommand("enable_camera_position_detect=YES")
def setup_cal_display(self):
"""
Sets up the initial calibration display, which contains a menu with
instructions.
"""
# show instructions
self.display.fill(self.menuscreen)
self.display.show()
def exit_cal_display(self):
"""Exits calibration display."""
self.clear_cal_display()
def record_abort_hide(self):
"""TODO: What does this do?"""
pass
def clear_cal_display(self):
"""Clears the calibration display"""
self.display.fill()
self.display.show()
def erase_cal_target(self):
"""TODO: What does this do?"""
self.clear_cal_display()
def draw_cal_target(self, x, y):
"""
Draws calibration target.
Arguments:
x -- The X coordinate of the target.
y -- The Y coordinate of the target.
"""
self.play_beep(pylink.CAL_TARG_BEEP)
self.screen.clear()
self.screen.draw_fixation(fixtype='dot', pos=(x,y))
self.display.fill(screen=self.screen)
self.display.show()
def play_beep(self, beepid):
"""
Plays a sound.
Arguments:
beepid -- A number that identifies the sound.
"""
if beepid == pylink.CAL_TARG_BEEP:
# For some reason, playing the beep here doesn't work, so we have
# to play it when the calibration target is drawn.
if EYELINKCALBEEP:
self.__target_beep__.play()
elif beepid == pylink.CAL_ERR_BEEP or beepid == pylink.DC_ERR_BEEP:
# show a picture
self.screen.clear()
self.screen.draw_text(text= \
"calibration lost, press 'q' to return to menu", pos= \
(self.xc,self.yc), center=True, font='mono', fontsize=12, \
antialias=True)
self.display.fill(self.screen)
self.display.show()
# play beep
self.__target_beep__error__.play()
elif beepid == pylink.CAL_GOOD_BEEP:
self.screen.clear()
if self.state == "calibration":
self.screen.draw_text(text= \
"Calibration succesfull, press 'v' to validate", pos= \
(self.xc,self.yc), center=True, font='mono', fontsize=12, \
antialias=True)
pass
elif self.state == "validation":
self.screen.draw_text(text= \
"Validation succesfull, press 'q' to return to menu", \
pos=(self.xc,self.yc), center=True, font='mono', fontsize= \
12, antialias=True)
pass
else:
self.screen.draw_text(text="Press 'q' to return to menu", pos= \
(self.xc,self.yc), center=True, font='mono', fontsize=12, \
antialias=True)
pass
# show screen
self.display.fill(self.screen)
self.display.show()
# play beep
self.__target_beep__done__.play()
else: # DC_GOOD_BEEP or DC_TARG_BEEP
pass
def getColorFromIndex(self, i):
"""
Maps a PyLink color code onto a color-name string.
Arguments:
i -- A PyLink color code.
Returns:
A color-name string.
"""
print 'getColorFromIndex(%s)' % i
if i == pylink.CR_HAIR_COLOR:
return 'white'
if i == pylink.PUPIL_HAIR_COLOR:
return 'yellow'
if i == pylink.PUPIL_BOX_COLOR:
return 'green'
if i == pylink.SEARCH_LIMIT_BOX_COLOR:
return 'red'
if i == pylink.MOUSE_CURSOR_COLOR:
return 'blue'
return 'black'
def draw_line(self, x1, y1, x2, y2, colorindex):
"""Unused"""
# Find out how this can be used
print 'draw_line() %s %s %s %s' % (x1, y1, x2, y2)
def draw_lozenge(self, x, y, width, height, colorindex):
"""Unused"""
# Find out how this can be used
print 'draw_lozenge() %s %s %s %s' % (x, y, width, height)
def get_mouse_state(self):
"""Unused"""
pass
def get_input_key(self):
"""
Gets an input key.
Returns:
A list containing a single pylink key identifier.
"""
try:
key, time = self.kb.get_key(keylist=None, timeout='default')
except:
self.esc_pressed = True
key = 'q'
if key == None:
return None
# Escape functions as a 'q' with the additional esc_pressed flag
if key == 'escape':
key = 'q'
self.esc_pressed = True
# Process regular keys
if key == "return":
keycode = pylink.ENTER_KEY
self.state = None
elif key == "space":
keycode = ord(" ")
elif key == "q":
keycode = pylink.ESC_KEY
self.state = None
elif key == "c":
keycode = ord("c")
self.state = "calibration"
elif key == "v":
keycode = ord("v")
self.state = "validation"
elif key == "a":
keycode = ord("a")
elif key == "up":
keycode = pylink.CURS_UP
elif key == "down":
keycode = pylink.CURS_DOWN
elif key == "left":
keycode = pylink.CURS_LEFT
elif key == "right":
keycode = pylink.CURS_RIGHT
else:
keycode = 0
# Convert key to PyLink keycode and return
return [pylink.KeyInput(keycode, 0)] # 0 = pygame.KMOD_NONE
def exit_image_display(self):
"""Exits the image display."""
self.clear_cal_display()
def alert_printf(self,msg):
"""
Prints alert message.
Arguments:
msg -- The message to be played.
"""
print "eyelink_graphics.alert_printf(): %s" % msg
def setup_image_display(self, width, height):
"""
Initializes the buffer that will contain the camera image.
Arguments:
width -- The width of the image.
height -- The height of the image.
"""
self.size = (width,height)
self.clear_cal_display()
self.last_mouse_state = -1
self.imagebuffer = array.array('l')
def image_title(self, text):
"""
TODO: What does this do?
Arguments:
text -- Unknown.
"""
pass
def draw_image_line(self, width, line, totlines, buff):
"""
Draws a single eye video frame, line by line.
Arguments:
width -- Width of the video.
line -- Line nr of current line.
totlines -- Total lines in video.
buff -- Frame buffer.
imagesize -- The size of the image, which is (usually?) 192x160 px.
"""
# If the buffer hasn't been filled yet, add a line.
for i in range(width):
try:
self.imagebuffer.append(self.pal[buff[i]])
except:
pass
# If the buffer is full, push it to the display.
if line == totlines:
# First create a PIL image, then convert it to a PyGame image, and
# then save it to a temporary file on disk. This juggling with
# formats is necessary to show the image without distortions under
# (so far) all conditions. Surprisingly, it doesn't cause any
# appreciable delays, relative to directly invoking PyGame or
# PsychoPy functions.
bufferv = self.imagebuffer.tostring()
img = Image.new("RGBX", self.size)
imgsz = self.xc, self.yc
img.fromstring(bufferv)
img = img.resize(imgsz)
img = pygame.image.fromstring(img.tostring(), imgsz, 'RGBX')
pygame.image.save(img, self.tmp_file)
# ... and then show the image.
self.screen.clear()
self.screen.draw_image(self.tmp_file)
self.display.fill(self.screen)
self.display.show()
# Clear the buffer for the next round!
self.imagebuffer = array.array('l')
def set_image_palette(self, r, g, b):
"""
Sets the image palette.
TODO: What this function actually does is highly mysterious. Figure it
out!
Arguments:
r -- The red channel.
g -- The green channel.
b -- The blue channel.
"""
self.imagebuffer = array.array('l')
self.clear_cal_display()
sz = len(r)
i = 0
self.pal = []
while i < sz:
rf = int(b[i])
gf = int(g[i])
bf = int(r[i])
self.pal.append((rf<<16) | (gf<<8) | (bf))
i += 1
class libeyelink(BaseEyeTracker):
MAX_TRY = 100
def __init__(self,
display,
resolution=settings.DISPSIZE,
data_file=settings.LOGFILENAME + ".edf",
fg_color=settings.FGC,
bg_color=settings.BGC,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
blink_threshold=settings.BLINKTHRESH,
force_drift_correct=True,
pupil_size_mode=settings.EYELINKPUPILSIZEMODE,
**args):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# try to import copy docstring (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, libeyelink)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
global _eyelink
# Make sure that we have a valid data file. The local_data_file may
# contain a folder. The eyelink_data_file is only a basename, i.e.
# without folder. The eyelink_data_file must be at most eight characters
# and end with a `.edf` extension.
self.local_data_file = data_file
self.eyelink_data_file = os.path.basename(data_file)
stem, ext = os.path.splitext(self.eyelink_data_file)
if len(stem) > 8 or ext.lower() != '.edf':
raise Exception(
"The EyeLink cannot handle filenames longer than eight "
"characters (excluding '.edf' extension).")
# properties
self.display = display
self.fontsize = 18
self.scr = Screen(disptype=settings.DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=["escape", "q"], timeout=1)
self.resolution = resolution
self.recording = False
self.saccade_velocity_treshold = saccade_velocity_threshold
self.saccade_acceleration_treshold = saccade_acceleration_threshold
self.blink_threshold = blink_threshold
self.eye_used = None
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.pupil_size_mode = pupil_size_mode
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
# degrees; maximal distance from fixation start (if gaze wanders beyond
# this, fixation has stopped)
self.fixtresh = 1.5
# milliseconds; amount of time gaze has to linger within self.fixtresh
# to be marked as a fixation
self.fixtimetresh = 100
# degrees per second; saccade velocity threshold
self.spdtresh = self.saccade_velocity_treshold
# degrees per second**2; saccade acceleration threshold
self.accthresh = self.saccade_acceleration_treshold
self.set_detection_type(eventdetection)
# weighted distance, used for determining whether a movement is due to
# measurement error (1 is ok, higher is more conservative and will
# result in only larger saccades to be detected)
self.weightdist = 10
# distance between participant and screen in cm
self.screendist = settings.SCREENDIST
# distance between participant and screen in cm
self.screensize = settings.SCREENSIZE
self.pixpercm = (self.resolution[0]/float(self.screensize[0]) + \
self.resolution[1]/float(self.screensize[1])) / 2.0
# only initialize eyelink once
if _eyelink == None:
try:
_eyelink = pylink.EyeLink()
except:
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to "
"connect to the tracker!")
# determine software version of tracker
self.tracker_software_ver = 0
self.eyelink_ver = pylink.getEYELINK().getTrackerVersion()
if self.eyelink_ver == 3:
tvstr = pylink.getEYELINK().getTrackerVersionString()
vindex = tvstr.find("EYELINK CL")
self.tracker_software_ver = int(float(tvstr[(vindex + \
len("EYELINK CL")):].strip()))
if self.eyelink_ver == 1:
self.eyelink_model = 'EyeLink I'
elif self.eyelink_ver == 2:
self.eyelink_model = 'EyeLink II'
elif self.eyelink_ver == 3:
self.eyelink_model = 'EyeLink 1000'
else:
self.eyelink_model = 'EyeLink (model unknown)'
# Open graphics
self.eyelink_graphics = EyelinkGraphics(self, _eyelink)
pylink.openGraphicsEx(self.eyelink_graphics)
# Optionally force drift correction. For some reason this must be done
# as (one of) the first things, otherwise a segmentation fault occurs.
if force_drift_correct:
try:
self.send_command('driftcorrect_cr_disable = OFF')
except:
print('Failed to force drift correction (EyeLink 1000 only)')
# Set pupil-size mode
if self.pupil_size_mode == 'area':
pylink.getEYELINK().setPupilSizeDiameter(False)
elif self.pupil_size_mode == 'diameter':
pylink.getEYELINK().setPupilSizeDiameter(True)
else:
raise Exception(
"pupil_size_mode should be 'area' or 'diameter', not %s" \
% self.pupil_size_mode)
pylink.getEYELINK().openDataFile(self.eyelink_data_file)
pylink.flushGetkeyQueue()
pylink.getEYELINK().setOfflineMode()
# notify eyelink of display resolution
self.send_command("screen_pixel_coords = 0 0 %d %d" % \
(self.resolution[0], self.resolution[1]))
# get some configuration stuff
if self.eyelink_ver >= 2:
self.send_command("select_parser_configuration 0")
if self.eyelink_ver == 2: # turn off scenelink camera stuff
self.send_command("scene_camera_gazemap = NO")
# set EDF file contents (this specifies which data is written to the EDF
# file)
self.send_command(
"file_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,MESSAGE,BUTTON"
)
if self.tracker_software_ver >= 4:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS,HTARGET"
)
else:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS")
# set link data (this specifies which data is sent through the link and
# thus can be used in gaze contingent displays)
self.send_command(
"link_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,BUTTON")
if self.tracker_software_ver >= 4:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS,HTARGET"
)
else:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS")
# not quite sure what this means (according to Sebastiaan Mathot, it
# might be the button that is used to end drift correction?)
self.send_command("button_function 5 'accept_target_fixation'")
if not self.connected():
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to connect "
"to the eyetracker!")
def send_command(self, cmd):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
pylink.getEYELINK().sendCommand(cmd)
def log(self, msg):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
pylink.getEYELINK().sendMessage(msg)
def status_msg(self, msg):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
print('status message: %s' % msg)
pylink.getEYELINK().sendCommand("record_status_message '%s'" % msg)
def connected(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
return pylink.getEYELINK().isConnected()
def calibrate(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
while True:
if self.recording:
raise Exception(
"Error in libeyelink.libeyelink.calibrate(): Trying to "
"calibrate after recording has started!")
# # # # #
# EyeLink calibration and validation
# attempt calibrate; confirm abort when esc pressed
while True:
self.eyelink_graphics.esc_pressed = False
pylink.getEYELINK().doTrackerSetup()
if not self.eyelink_graphics.esc_pressed:
break
self.confirm_abort_experiment()
# If we are using the built-in EyeLink event detection, we don't need
# the RMS calibration routine.
if self.eventdetection == 'native':
return
# # # # #
# RMS calibration
while True:
# present instructions
self.display.fill() # clear display
self.scr.draw_text(text= \
"Noise calibration: please look at the dot\n\n(press space to start)",
pos=(self.resolution[0]/2, int(self.resolution[1]*0.2)),
center=True, fontsize=self.fontsize)
self.scr.draw_fixation(fixtype='dot')
self.display.fill(self.scr)
self.display.show()
self.scr.clear() # clear screen again
# wait for spacepress
self.kb.get_key(keylist=['space'], timeout=None)
# start recording
self.log("PYGAZE RMS CALIBRATION START")
self.start_recording()
# show fixation
self.display.fill()
self.scr.draw_fixation(fixtype='dot')
self.display.fill(self.scr)
self.display.show()
self.scr.clear()
# wait for a bit, to allow participant to fixate
clock.pause(500)
# get samples
# samplelist, prefilled with 1 sample to prevent sl[-1] from producing
# an error; first sample will be ignored for RMS calculation
sl = [self.sample()]
t0 = clock.get_time() # starting time
while clock.get_time() - t0 < 1000:
s = self.sample() # sample
if s != sl[-1] and s != (-1, -1) and s != (0, 0):
sl.append(s)
# stop recording
self.log("PYGAZE RMS CALIBRATION END")
self.stop_recording()
# calculate RMS noise
Xvar = []
Yvar = []
for i in range(2, len(sl)):
Xvar.append((sl[i][0] - sl[i - 1][0])**2)
Yvar.append((sl[i][1] - sl[i - 1][1])**2)
if Xvar and Yvar: # check if properly recorded to avoid risk of division by zero error
XRMS = (sum(Xvar) / len(Xvar))**0.5
YRMS = (sum(Yvar) / len(Yvar))**0.5
self.pxdsttresh = (XRMS, YRMS)
# recalculate thresholds (degrees to pixels)
self.pxfixtresh = deg2pix(self.screendist, self.fixtresh,
self.pixpercm)
self.pxspdtresh = deg2pix(
self.screendist, self.spdtresh,
self.pixpercm) / 1000.0 # in pixels per millisecons
self.pxacctresh = deg2pix(
self.screendist, self.accthresh,
self.pixpercm) / 1000.0 # in pixels per millisecond**2
return
else: # if nothing recorded, display message saying so
self.display.fill()
self.scr.draw_text(text = \
"Noise calibration failed.\n\nPress r to retry,\nor press space to return to calibration screen.", \
pos=(self.resolution[0]/2, int(self.resolution[1]*0.2)), \
center=True, fontsize=self.fontsize)
self.display.fill(self.scr)
self.display.show()
self.scr.clear()
# wait for space or r press, if r restart noise calibration, if space return to calibration menu
keypressed = self.kb.get_key(keylist=['space', 'r'],
timeout=None)
if keypressed[0] == 'space':
break
def drift_correction(self, pos=None, fix_triggered=False):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if self.recording:
raise Exception(
"Error in libeyelink.libeyelink.drift_correction(): Trying to "
"perform drift correction after recording has started!")
if not self.connected():
raise Exception(
"Error in libeyelink.libeyelink.drift_correction(): The "
"eyelink is not connected!")
if pos == None:
pos = self.resolution[0] / 2, self.resolution[1] / 2
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
return self.manual_drift_correction(pos)
def manual_drift_correction(self, pos):
"""
Performs a manual, i.e. spacebar-triggered drift correction.
Arguments:
pos -- The positionf or the drift-correction target.
Returns:
True if drift correction was successfull, False otherwise.
"""
self.draw_drift_correction_target(pos[0], pos[1])
self.eyelink_graphics.esc_pressed = False
try:
# The 0 parameters indicate that the display should not be cleared
# and we should not be allowed to fall back to the set-up screen.
error = pylink.getEYELINK().doDriftCorrect(pos[0], pos[1], 0, 0)
except:
error = -1
# A 0 exit code means successful drift correction
if error == 0:
return True
# If escape was pressed, we present the confirm abort screen
if self.eyelink_graphics.esc_pressed:
self.confirm_abort_experiment()
# If 'q' was pressed, we drop back to the calibration screen
else:
self.calibrate()
return False
def prepare_drift_correction(self, pos):
"""Puts the tracker in drift correction mode"""
# start collecting samples in drift correction mode
self.send_command("heuristic_filter = ON")
self.send_command("drift_correction_targets = %d %d" % pos)
self.send_command("start_drift_correction data = 0 0 1 0")
pylink.msecDelay(50)
# wait for a bit until samples start coming in (again, not sure if this
# is indeed what's going on)
if not pylink.getEYELINK().waitForBlockStart(100, 1, 0):
print(
"WARNING libeyelink.libeyelink.prepare_drift_correction(): "
"Failed to perform drift correction (waitForBlockStart error)")
def fix_triggered_drift_correction(self,
pos=None,
min_samples=30,
max_dev=60,
reset_threshold=10):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if self.recording:
raise Exception(
"Error in libeyelink.libeyelink.fix_triggered_drift_correction(): "
"Trying to perform drift correction after recording has started!"
)
self.recording = True
if pos == None:
pos = self.resolution[0] / 2, self.resolution[1] / 2
self.prepare_drift_correction(pos)
self.draw_drift_correction_target(pos[0], pos[1])
# loop until we have enough samples
lx = []
ly = []
while len(lx) < min_samples:
# Check whether the EyeLink is put into set-up mode on the EyeLink
# PC and, if so, jump to the calibration menu.
if pylink.getEYELINK().getCurrentMode() == pylink.IN_SETUP_MODE:
self.recording = False
self.calibrate()
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"'q' pressed")
return False
# pressing escape enters the calibration screen
resp = self.kb.get_key(keylist=["escape", "q"], timeout=1)[0]
if resp == 'escape':
self.recording = False
self.confirm_abort_experiment()
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"'escape' pressed")
return False
elif resp == 'q':
self.recording = False
self.calibrate()
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"'q' pressed")
return False
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample,
# start from scratch.
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold or \
abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# Collect a sample
else:
lx.append(x)
ly.append(y)
# If we have enough samples to perform a drift correction ...
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0])**2 + (avg_y - pos[1])**2)**0.5
# emulate spacebar press on succes
pylink.getEYELINK().sendKeybutton(32, 0, pylink.KB_PRESS)
# getCalibrationResult() returns 0 on success and an exception
# or a non-zero value otherwise
result = -1
try:
result = pylink.getEYELINK().getCalibrationResult()
except:
lx = []
ly = []
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"try again")
if result != 0:
try:
result = pylink.getEYELINK().getCalibrationResult()
except:
lx = []
ly = []
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): "
"try again")
# apply drift correction
pylink.getEYELINK().applyDriftCorrect()
self.recording = False
print(
"libeyelink.libeyelink.fix_triggered_drift_correction(): success")
return True
def start_recording(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.recording = True
i = 0
while True:
# params: write samples, write event, send samples, send events
print(u'starting recording ...')
error = pylink.getEYELINK().startRecording(1, 1, 1, 1)
print(u'returned %s' % error)
if not error:
break
if i > self.MAX_TRY:
raise Exception(
"Error in libeyelink.libeyelink.start_recording(): Failed "
"to start recording!")
self.close()
clock.expend()
i += 1
print(
("WARNING libeyelink.libeyelink.start_recording(): Failed to "
"start recording (attempt %d of %d)") % (i, self.MAX_TRY))
pylink.msecDelay(100)
# don't know what this is
print(u'Start realtime mode ...')
pylink.msecDelay(100)
pylink.beginRealTimeMode(100)
# wait a bit until samples start coming in
print(u'Wait for block start ...')
pylink.msecDelay(100)
if not pylink.getEYELINK().waitForBlockStart(100, 1, 0):
raise Exception(
"Error in libeyelink.libeyelink.start_recording(): Failed to "
"start recording (waitForBlockStart error)!")
print(u'done ...')
def stop_recording(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
print(u'stopping recording ...')
self.recording = False
pylink.endRealTimeMode()
pylink.getEYELINK().setOfflineMode()
pylink.msecDelay(500)
print(u'done ...')
def close(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.eyelink_graphics.close()
if self.recording:
self.stop_recording()
# close data file and transfer it to the experimental PC
print("libeyelink.libeyelink.close(): Closing data file")
pylink.getEYELINK().closeDataFile()
pylink.msecDelay(500)
print("libeyelink.libeyelink.close(): Transferring %s to %s" \
% (self.eyelink_data_file, self.local_data_file))
# During data transfer, suppress output
_out = sys.stdout
with open(os.devnull, 'w') as fd:
sys.stdout = fd
pylink.getEYELINK().receiveDataFile(self.eyelink_data_file,
self.local_data_file)
sys.stdout = _out
pylink.msecDelay(500)
print("libeyelink.libeyelink.close(): Closing eyelink")
pylink.getEYELINK().close()
pylink.msecDelay(500)
def set_eye_used(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.eye_used = pylink.getEYELINK().eyeAvailable()
if self.eye_used == self.right_eye:
self.log_var("eye_used", "right")
elif self.eye_used == self.left_eye or self.eye_used == self.binocular:
self.log_var("eye_used", "left")
self.eye_used = self.left_eye
else:
print("WARNING libeyelink.libeyelink.set_eye_used(): Failed to "
"determine which eye is being recorded")
def pupil_size(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.pupil_size(): Recording was "
"not started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
# get newest sample
s = pylink.getEYELINK().getNewestSample()
# check if sample is new
if s != None:
# right eye
if self.eye_used == self.right_eye and s.isRightSample():
ps = s.getRightEye().getPupilSize()
# left eye
elif self.eye_used == self.left_eye and s.isLeftSample():
ps = s.getLeftEye().getPupilSize()
# invalid
else:
ps = -1
# set new pupil size as previous pupil size
self.prevps = ps
# if no new sample is available, use old data
else:
ps = self.prevps
return ps
def sample(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.sample(): Recording was not "
"started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
s = pylink.getEYELINK().getNewestSample()
if s != None:
if self.eye_used == self.right_eye and s.isRightSample():
gaze = s.getRightEye().getGaze()
elif self.eye_used == self.left_eye and s.isLeftSample():
gaze = s.getLeftEye().getGaze()
else:
gaze = (-1, -1)
self.prevsample = gaze[:]
else:
gaze = self.prevsample[:]
return gaze
def set_detection_type(self, eventdetection):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if eventdetection in ['pygaze', 'native']:
self.eventdetection = eventdetection
return (self.eventdetection, self.eventdetection, self.eventdetection)
def _get_eyelink_clock_async(self):
"""
Retrieve time differenece between tracker timestamps and
current clock time upheld in the pygaze environment.
Note that this is not guaranteed to be a static time difference, the
clocks might run at different speeds. Therefore you should consider
running this function every time you utilize on this time difference.
Returns:
The tracker time minus the clock time
"""
return pylink.getEYELINK().trackerTime() - clock.get_time()
def wait_for_event(self, event):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.wait_for_event(): Recording "
"was not started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
if self.eventdetection == 'native':
# since the link buffer was not have been polled, old data has
# accumulated in the buffer -- so ignore events that are old:
t0 = clock.get_time() # time of call
while True:
d = pylink.getEYELINK().getNextData()
if d == event:
float_data = pylink.getEYELINK().getFloatData()
# corresponding clock_time
tc = float_data.getTime() - self._get_eyelink_clock_async()
if tc > t0:
return tc, float_data
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
("Error in libeyelink.libeyelink.wait_for_event: eventcode %s "
"is not supported") % event)
return outcome
def wait_for_saccade_start(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.STARTSACC)
return t, d.getStartGaze()
# # # # #
# PyGaze method
else:
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0] - prevpos[0]
sy = newpos[1] - prevpos[1]
# weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means
# movement larger than RMS noise
if (sx/self.pxdsttresh[0])**2 + (sy/self.pxdsttresh[1])**2 \
> self.weightdist:
# calculate distance
# intersampledistance = speed in pixels/ms
s = ((sx)**2 + (sy)**2)**0.5
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0
) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above
# threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def wait_for_saccade_end(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.ENDSACC)
return t, d.getStartGaze(), d.getEndGaze()
# # # # #
# PyGaze method
else:
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
# = intersample distance = speed in px/sample
s = ((prevpos[0] - spos[0])**2 + (prevpos[1] - spos[1])**2)**0.5
v0 = s / (t1 - t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
# = speed in pixels/sample
s = ((newpos[0]-prevpos[0])**2 + \
(newpos[1]-prevpos[1])**2)**0.5
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
# acceleration in pixels/sample**2 (actually is
# v1-v0 / t1-t0; but t1-t0 = 1 sample)
a = (v1 - v0) / (t1 - t0)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1*self.pxacctresh and \
a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_fixation_start(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.STARTFIX)
return t, d.getTime(), d.getStartGaze()
# # # # #
# PyGaze method
else:
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > \
self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_fixation_end(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.ENDFIX)
return t, d.getTime(), d.getStartGaze()
# # # # #
# PyGaze method
else:
# function assumes that a 'fixation' has ended when a deviation of
# more than fixtresh from the initial 'fixation' position has been
# detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > \
self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_blink_start(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.STARTBLINK)
return t, d.getTime()
# # # # #
# PyGaze method
else:
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed 150 ms
if clock.get_time() - t0 >= self.blink_threshold:
# return timestamp of blink start
return t0
def wait_for_blink_end(self):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# # # # #
# EyeLink method
if self.eventdetection == 'native':
t, d = self.wait_for_event(pylink.ENDBLINK)
return t
# # # # #
# PyGaze method
else:
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def set_draw_calibration_target_func(self, func):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.eyelink_graphics.draw_cal_target = func
# ***
#
# Internal functions below
#
# ***
def is_valid_sample(self, gazepos):
"""
Checks if the sample provided is valid, based on EyeLink specific
criteria.
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (-1, -1):
return False
# in any other case, the sample is valid
return True
def confirm_abort_experiment(self):
"""
Asks for confirmation before aborting the experiment. Displays a
confirmation screen, collects the response, and acts accordingly.
Exceptions:
Raises a response_error upon confirmation.
Returns:
False if no confirmation was given.
"""
# Display the confirmation screen
scr = Screen(disptype=settings.DISPTYPE)
kb = Keyboard(timeout=5000)
yc = settings.DISPSIZE[1] / 2
xc = settings.DISPSIZE[0] / 2
ld = 40 # Line height
scr.draw_text(u'Really abort experiment?',
pos=(xc, yc - 3 * ld),
fontsize=self.fontsize)
scr.draw_text(u'Press \'Y\' to abort',
pos=(xc, yc - 0.5 * ld),
fontsize=self.fontsize)
scr.draw_text(u'Press any other key or wait 5s to go to setup',
pos=(xc, yc + 0.5 * ld),
fontsize=self.fontsize)
self.display.fill(scr)
self.display.show()
# process the response:
try:
key, time = kb.get_key()
except:
return False
# if confirmation, close experiment
if key == u'y':
raise Exception(u'The experiment was aborted')
self.eyelink_graphics.esc_pressed = False
return False
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.scr.clear()
self.scr.draw_fixation(fixtype='dot',
colour=settings.FGC,
pos=(x, y),
pw=0,
diameter=12)
self.display.fill(self.scr)
self.display.show()
class EyeLogicTracker(BaseEyeTracker):
## Initializes the EyeTracker object.
def __init__(self, display,
logfile=settings.LOGFILE, \
eventdetection=settings.EVENTDETECTION, \
saccade_velocity_threshold=35, \
saccade_acceleration_threshold=9500, \
blink_threshold=settings.BLINKTHRESH, \
**args):
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, EyeLogicTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
self.disp = display
self.screen = Screen()
self.dispsize = self.disp.dispsize # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# show a message
self.screen.clear()
self.screen.draw_text(
text="Initialising the eye tracker, please wait...",
fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# output file properties
self.logfile = logfile
# eye tracker properties
self._recording = Event()
self._recording.clear()
self._calibrated = Event()
self._calibrated.clear()
self.eye_used = 2 # 0=left, 1=right, 2=binocular
self.sampleLock = Lock()
self.lastSample = None
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
# event detection properties
self.pxfixtresh = 50;
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self._log_vars = [ \
"timestampMicroSec", \
"index", \
"porFilteredX", \
"porFilteredY", \
"porLeftX", \
"porLeftY", \
"pupilRadiusLeft", \
"porRightX", \
"porRightY", \
"pupilRadiusRight", \
]
# Open a new log file.
dir_name = os.path.dirname(logfile)
file_name = os.path.basename(logfile)
name, ext = os.path.splitext(file_name)
self._data_file_path = os.path.join(dir_name, name+".eyelogic.csv")
self._log_file = open(self._data_file_path, "w")
# Write a header to the log.
header = ["TYPE"]
header.extend(self._log_vars)
self._sep = ";"
self._log_file.write("Sep="+self._sep+"\n")
self._log_file.write(self._sep.join(map(str, header)))
# Create a lock to prevent simultaneous access to the log file.
self._logging_queue = Queue()
self._logging_queue_empty = Event()
self._logging_queue_empty.set()
self._connected = Event()
self._connected.set()
self._log_counter = 0
self._log_consolidation_freq = 60
self._logging_thread = Thread( target=self.loggingThread, \
name='PyGaze_EyeLogic_Logging', args=[])
global g_api
g_api = self
# log
self.log("pygaze initiation")
#self.log("experiment = {}".format(self.description))
#self.log("participant = {}".format(self.participant))
self.log("display resolution = {}x{}".format(self.dispsize[0], \
self.dispsize[1]))
self.log("display size in cm = {}x{}".format(self.screensize[0], \
self.screensize[1]))
self.log("fixation threshold = {} degrees".format(self.fixtresh))
self.log("speed threshold = {} degrees/second".format(self.spdtresh))
self.log("acceleration threshold = {} degrees/second**2".format( \
self.accthresh))
# connect
self.api = ELApi( "PyGaze" )
self.api.registerGazeSampleCallback( gazeSampleCallback )
self.api.registerEventCallback( eventCallback )
resultConnect = self.api.connect()
if (resultConnect != ELApi.ReturnConnect.SUCCESS):
self._connected.clear()
raise Exception("Cannot connect to EyeLogic server = {}".format(errorstringConnect(resultConnect)))
self._connected.set()
screenConfig = self.api.getScreenConfig()
self.log("eye tracker is mounted on screen {}".format(screenConfig.id))
self.rawResolution = (screenConfig.resolutionX, screenConfig.resolutionY)
self.log("raw screen resolution = {}x{}".format(
self.rawResolution[0], self.rawResolution[1]))
self.log("end pygaze initiation")
deviceConfig = self.api.getDeviceConfig()
if (deviceConfig.deviceSerial == 0):
raise Exception("no eye tracking device connected")
if (len(deviceConfig.frameRates) == 0):
raise Exception("failed to read out device configuration")
g_api.sampleRate = deviceConfig.frameRates[0]
g_api.sampleTime = 1000.0 / g_api.sampleRate
g_api.log("samplerate = {} Hz".format(g_api.sampleRate))
g_api.log("sampletime = {} ms".format(g_api.sampleTime))
self._logging_thread.start()
self.screen.clear()
self.disp.fill(self.screen)
self.disp.show()
def loggingThread(self):
while self._connected.is_set():
# Check if the sample Queue is empty.
if self._logging_queue.empty():
# Signal to other Threads that the logging Queue is empty.
if not self._logging_queue_empty.is_set():
self._logging_queue_empty.set()
# Process data from the Queue.
else:
# Signal to other Threads that the Queue isn't empty.
if self._logging_queue_empty.is_set():
self._logging_queue_empty.clear()
# Get the next object from the Queue.
sample = self._logging_queue.get()
# Log the message string and/or the sample.
if type(sample) in [tuple, list]:
self._write_tuple(sample)
elif type(sample) == ELGazeSample:
self._write_sample(sample)
else:
print("WARNING = Unrecognised object in log queue = '{}'".format( \
sample))
# Increment the log counter.
self._log_counter += 1
# Check if the log file needs to be consolidated.
if self._log_counter % self._log_consolidation_freq == 0:
# Internal buffer to RAM.
self._log_file.flush()
# RAM to disk.
os.fsync(self._log_file.fileno())
# Release the log file lock.
def _write_sample(self, sample):
# Construct a list with the sample data.
line = ["DAT"]
for var in self._log_vars:
line.append(sample.__getattribute__(var))
# Log the sample to the log file.
self._log_file.write("\n" + self._sep.join(map(str, line)))
def _write_tuple(self, tup):
# Construct a list values that need to be logged.
line = []
# Add the values that need to be logged. Usually this will be ("MSG",
# timestamp, message).
line.extend(tup)
# Pad the list so that it will be of equal length to the sample
# lines, which makes it easier to be read into a spreadsheet editor
# and by some read_csv functions.
line.extend([""] * (len(self._log_vars) - len(line) - 1))
# Log the line to the log file.
self._log_file.write("\n" + self._sep.join(map(str, line)))
## Calibrates the eye tracking system.
def calibrate(self):
#self.screen.clear()
#self.screen.draw_text(
# text="Calibrate EyeTracker",
# fontsize=20)
#self.disp.fill(self.screen)
#self.disp.show()
if (not self._recording.is_set()):
resultTracking = self.api.requestTracking(0)
if (resultTracking != ELApi.ReturnStart.SUCCESS):
raise Exception("unable to start eye tracker")
resultCalibrate = self.api.calibrate(0)
if (resultCalibrate != ELApi.ReturnCalibrate.SUCCESS):
self.api.unrequestTracking()
self.errorbeep.play()
raise Exception("Calibration failed = {}".format(errorstringCalibrate(resultCalibrate)))
self._calibrated.set()
# NOISE CALIBRATION
self.screen.clear()
self.screen.draw_text(
text="Noise calibration. Please look at the dot, and press any key to start.",
fontsize=20, \
pos=(int(self.dispsize[0]/2),int(self.dispsize[1]*0.3)))
x = int(float(self.dispsize[0]) / 2.0)
y = int(float(self.dispsize[1]) / 2.0)
self.screen.draw_fixation(fixtype="dot", pos=(x,y))
self.disp.fill(self.screen)
self.disp.show()
self.kb.get_key(keylist=None, timeout=None, flush=True)
# wait for a bit, to allow participant to fixate
clock.pause(500)
# get distance to screen
screendist = 0
i = 0
while screendist == 0 and i < self.maxtries:
i = i+1
self.sampleLock.acquire()
if (self.lastSample is not None):
if self.eye_used != 1 and self.lastSample.eyePositionLeftZ != ELInvalidValue:
screendist = self.lastSample.eyePositionLeftZ / 10.0 # eyePositionZ is in mm; screendist is in cm
elif self.eye_used != 0 and self.lastSample.eyePositionRightZ != ELInvalidValue:
screendist = self.lastSample.eyePositionRightZ / 10.0
self.sampleLock.release()
clock.pause(int(self.sampleTime))
if i >= self.maxtries:
self.api.unrequestTracking()
self.errorbeep.play()
raise Exception("unable to receive gaze data for noise calibration")
# get samples
sl = [self.sample()] # samplelist, prefilled with 1 sample to prevent sl[-1] from producing an error; first sample will be ignored for RMS calculation
t0 = clock.get_time() # starting time
while clock.get_time() - t0 < 1000:
s = self.sample() # sample
if s[0] != -1 and s[1] != -1 and s[0] != ELInvalidValue and s[1] != ELInvalidValue:
sl.append(s)
clock.pause(int(self.sampleTime))
if (len(sl) < 2):
if (not self._recording.is_set()):
self.api.unrequestTracking()
return False
# calculate RMS noise
Xvar = []
Yvar = []
Xmean = 0.
Ymean = 0.
for i in range(2,len(sl)):
Xvar.append((sl[i][0]-sl[i-1][0])**2)
Yvar.append((sl[i][1]-sl[i-1][1])**2)
Xmean += sl[i][0]
Ymean += sl[i][1]
XRMS = (sum(Xvar) / len(Xvar))**0.5
YRMS = (sum(Yvar) / len(Yvar))**0.5
Xmean = Xmean / (len(sl)-2)
Ymean = Ymean / (len(sl)-2)
self.pxdsttresh = (XRMS, YRMS)
# calculate pixels per cm
pixpercm = (self.dispsize[0]/float(self.screensize[0]) + self.dispsize[1]/float(self.screensize[1])) / 2
# get accuracy
accuracyPxX = abs( Xmean - x )
accuracyPxY = abs( Ymean - y )
self.accuracy = ( pix2deg(screendist, accuracyPxX, pixpercm), \
pix2deg(screendist, accuracyPxY, pixpercm) )
# calculate thresholds based on tracker settings
self.pxfixtresh = deg2pix(screendist, self.fixtresh, pixpercm)
self.pxaccuracy = (accuracyPxX, accuracyPxY )
self.pxspdtresh = deg2pix(screendist, self.spdtresh/1000.0, pixpercm) # in pixels per millisecond
self.pxacctresh = deg2pix(screendist, self.accthresh/1000.0, pixpercm) # in pixels per millisecond**2
## log
self.log("pygaze calibration")
self.log("accuracy (degrees) = X={}, Y={}".format( \
self.accuracy[0], self.accuracy[1] ))
self.log("accuracy (in pixels) = X={}, Y={}".format( \
self.pxaccuracy[0], self.pxaccuracy[1]))
self.log("precision (RMS noise in pixels) = X={}, Y={}".format( \
self.pxdsttresh[0], self.pxdsttresh[1]))
self.log("distance between participant and display = {} cm".format(screendist))
self.log("fixation threshold = {} pixels".format(self.pxfixtresh))
self.log("speed threshold = {} pixels/ms".format(self.pxspdtresh))
self.log("acceleration threshold = {} pixels/ms**2".format(self.pxacctresh))
if (not self._recording.is_set()):
self.api.unrequestTracking()
return True
## Neatly closes connection to tracker.
def close(self):
if self._recording.is_set():
self.stop_recording()
# Wait until the Queue is empty, or until 60 seconds have passed.
queue_empty = self._logging_queue_empty.wait(timeout=15.0)
if not queue_empty:
print("WARNING = Logging Thread timeout occurred; something might have gone wrong!")
# Signal to the Threads to stop.
self._connected.clear()
# Close the log file.
self._log_file.close()
# Close the connection.
self.api.disconnect()
self._connected = False
## Checks if the tracker is connected.
def connected(self):
isConnected = self.api.isConnected()
if isConnected:
self._connected.set()
else:
self._connected.clear()
return isConnected
## Performs a drift check
def drift_correction(self, pos=None, fix_triggered=False):
return True
## Performs a fixation triggered drift correction by collecting
# a number of samples and calculating the average distance from the
# fixation position.
def fix_triggered_drift_correction(self, pos=None, min_samples=10, max_dev=60, reset_threshold=30):
pass
## Returns the difference between tracker time and PyGaze time,
# which can be used to synchronize timing
def get_eyetracker_clock_async(self):
return 0
## Writes a message to the log file.
def log(self, msg):
# Get current timestamp.
self.sampleLock.acquire()
if self.lastSample is None:
t = 0
else:
t = self.lastSample.timestampMicroSec
self.sampleLock.release()
# Construct a tuple, and add it to the queue.
self._logging_queue.put(("MSG", t, msg))
## Writes a variable's name and value to the log file
def log_var(self, var, val):
pass
## Returns the newest pupil size sample
def pupil_size(self):
self.sampleLock.acquire()
pupilSize = -1
if (self.lastSample is not None):
if self.eye_used == 0:
pupilSize = 2.*self.lastSample.pupilRadiusLeft;
elif self.eye_used == 1:
pupilSize = 2.*self.lastSample.pupilRadiusRight;
elif self.eye_used == 2:
pupilSize = self.lastSample.pupilRadiusLeft + self.lastSample.pupilRadiusRight;
self.sampleLock.release()
return pupilSize
## Returns newest available gaze position.
def sample(self):
self.sampleLock.acquire()
por = (-1, -1)
if (self.lastSample is not None):
if self.eye_used == 0:
por = (self.lastSample.porLeftX, self.lastSample.porLeftY)
elif self.eye_used == 1:
por = (self.lastSample.porRightX, self.lastSample.porRightY)
elif self.eye_used == 2:
por = (self.lastSample.porFilteredX, self.lastSample.porFilteredY)
self.sampleLock.release()
return por
# Directly sends a command to the eye tracker.
def send_command(self, cmd):
pass
## Set the event detection type to either PyGaze algorithms, or
# native algorithms.
def set_detection_type(self, eventdetection):
# detection type for saccades, fixations, blinks (pygaze or native)
return ('pygaze','pygaze','pygaze')
## Specifies a custom function to draw the calibration target.
def set_draw_calibration_target_func(self, func):
pass
## Specifies a custom function to draw the drift-correction target.
def set_draw_drift_correction_target_func(self, func):
pass
## Logs the eye_used variable, based on which eye was specified
# (if both eyes are being tracked, the left eye is used)
def set_eye_used(self):
pass
## Starts recording.
def start_recording(self):
resultTracking = self.api.requestTracking(0)
if (resultTracking != ELApi.ReturnStart.SUCCESS):
raise Exception("unable to start eye tracker")
self._recording.set()
## Sends a status message to the eye tracker, which is displayed in the tracker's GUI
def status_msg(self, msg):
pass
## Stops recording.
def stop_recording(self):
self.api.unrequestTracking()
self._recording.clear()
## Waits for an event.
def wait_for_event(self, event):
print("waitforevent", flush=True)
if event == 3: # STARTBLINK
return self.wait_for_blink_start()
elif event == 4: # ENDBLINK
return self.wait_for_blink_end()
elif event == 5: # STARTSACC
return self.wait_for_saccade_start()
elif event == 6: # ENDSACC
return self.wait_for_saccade_end()
elif event == 7: # STARTFIX
return self.wait_for_fixation_start()
elif event == 8: # ENDFIX
return self.wait_for_fixation_end()
else:
raise Exception("wait_for_event({}) is not supported".format(event))
## Waits for a blink end and returns the blink ending time.
def wait_for_blink_end(self):
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
## Waits for a blink start and returns the blink starting time.
def wait_for_blink_start(self):
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed BLINKTHRESH
if clock.get_time()-t0 >= self.blinkthresh:
# return timestamp of blink start
return t0
## Returns time and gaze position when a fixation has ended.
def wait_for_fixation_end(self):
print("wait_for_fixation_end", flush=True)
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
## Returns starting time and position when a fixation is started.
def wait_for_fixation_start(self):
print("wait_for_fixation_start", flush=True)
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
## Returns ending time, starting and end position when a saccade is
# ended.
def wait_for_saccade_end(self):
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0]-spos[0])**2 + (prevpos[1]-spos[1])**2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1-t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0]-prevpos[0])**2 + (newpos[1]-prevpos[1])**2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1-t0)
# calculate acceleration
a = (v1-v0) / (t1-t0) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1*self.pxacctresh and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
## Returns starting time and starting position when a saccade is started.
def wait_for_saccade_start(self):
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0]-prevpos[0]; sy = newpos[1]-prevpos[1]
if (sx/self.pxdsttresh[0])**2 + (sy/self.pxdsttresh[1])**2 > self.weightdist: # weigthed distance = (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1-t0)
# calculate acceleration
a = (v1-v0) / (t1-t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def __init__(self,
display,
address='192.168.71.50',
udpport=49152,
logfile=settings.LOGFILE,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
blink_threshold=settings.BLINKTHRESH,
**args):
"""Initializes a TobiiProGlassesTracker instance
arguments
display -- a pygaze.display.Display instance
keyword arguments
address -- internal ipv4/ipv6 address for Tobii Pro Glasses 2 (default =
'192.168.71.50', for IpV6 address use square brackets [fe80::xxxx:xxxx:xxxx:xxxx])
udpport -- UDP port number for Tobii Pro Glasses data streaming (default = 49152)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, TobiiProGlassesTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = settings.DISPSIZE # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.screendist = settings.SCREENDIST # distance between participant and screen in cm
self.pixpercm = (self.dispsize[0] / float(self.screensize[0]) +
self.dispsize[1] / float(self.screensize[1])) / 2.0
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# output file properties
self.outputfile = logfile
self.description = "experiment" # TODO: EXPERIMENT NAME
self.participant = "participant" # TODO: PP NAME
# eye tracker properties
self.eye_used = 0 # 0=left, 1=right, 2=binocular
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1, -1)
# validation properties
self.nvalsamples = 1000 # samples for one validation point
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
self.tobiiglasses = TobiiGlassesController(udpport, address)
self.triggers_values = {}
self.logging = False
self.current_recording_id = None
self.current_participant_id = None
self.current_project_id = None
def __init__(self, display, logfile=settings.LOGFILE,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
blink_threshold=settings.BLINKTHRESH, **args):
"""Initializes a TobiiProTracker instance
arguments
display -- a pygaze.display.Display instance
keyword arguments
None
"""
self.gaze = []
self.disp = display
# initialize a screen
self.screen = Screen()
# initialize keyboard
self.kb = Keyboard(keylist=['space', 'escape', 'q','enter'], timeout=1)
self.recording = False
self.screendist = settings.SCREENDIST
if hasattr(settings, 'TRACKERSERIALNUMBER'):
# Search for a specific eye tracker
self.eyetrackers = [t for t in tr.find_all_eyetrackers() if t.serial_number == settings.TRACKERSERIALNUMBER]
else:
# Search for all eye trackers (The first one found will be selected)
self.eyetrackers = tr.find_all_eyetrackers()
if self.eyetrackers:
self.eyetracker = self.eyetrackers[0]
else:
print("WARNING! libtobii.TobiiProTracker.__init__: no eye trackers found!")
self.LEFT_EYE = 0
self.RIGHT_EYE = 1
self.BINOCULAR = 2
self.eye_used = 0 # 0=left, 1=right, 2=binocular
# calibration and validation points
lb = 0.1 # left bound
xc = 0.5 # horizontal center
rb = 0.9 # right bound
ub = 0.1 # upper bound
yc = 0.5 # vertical center
bb = 0.9 # bottom bound
self.points_to_calibrate = [self._norm_2_px(p) for p in [(lb, ub), (xc,ub), (rb, ub), (lb,yc), (xc, yc),(rb,yc), (lb, bb),(xc,bb),(rb, bb)]]
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
self.screensize = settings.SCREENSIZE # display size in cm
self.pixpercm = (self.disp.dispsize[0] / float(self.screensize[0]) + self.disp.dispsize[1] / float(self.screensize[1])) / 2.0
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = self._deg2pix(self.screendist, self.errdist, self.pixpercm)
self.event_data = []
self.t0 = None
self._write_enabled = True
self.datafile = open("{0}_TOBII_output.tsv".format(logfile), 'w')
# initiation report
self.datafile.write("pygaze initiation report start\n")
self.datafile.write("display resolution: %sx%s\n" % (self.disp.dispsize[0], self.disp.dispsize[1]))
self.datafile.write("display size in cm: %sx%s\n" % (self.screensize[0], self.screensize[1]))
self.datafile.write("fixation threshold: %s degrees\n" % self.fixtresh)
self.datafile.write("speed threshold: %s degrees/second\n" % self.spdtresh)
self.datafile.write("acceleration threshold: %s degrees/second**2\n" % self.accthresh)
self.datafile.write("pygaze initiation report end\n")
class TobiiProTracker(BaseEyeTracker):
"""A class for Tobii Pro EyeTracker objects"""
def __init__(self, display, logfile=settings.LOGFILE,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
blink_threshold=settings.BLINKTHRESH, **args):
"""Initializes a TobiiProTracker instance
arguments
display -- a pygaze.display.Display instance
keyword arguments
None
"""
self.gaze = []
self.disp = display
# initialize a screen
self.screen = Screen()
# initialize keyboard
self.kb = Keyboard(keylist=['space', 'escape', 'q','enter'], timeout=1)
self.recording = False
self.screendist = settings.SCREENDIST
if hasattr(settings, 'TRACKERSERIALNUMBER'):
# Search for a specific eye tracker
self.eyetrackers = [t for t in tr.find_all_eyetrackers() if t.serial_number == settings.TRACKERSERIALNUMBER]
else:
# Search for all eye trackers (The first one found will be selected)
self.eyetrackers = tr.find_all_eyetrackers()
if self.eyetrackers:
self.eyetracker = self.eyetrackers[0]
else:
print("WARNING! libtobii.TobiiProTracker.__init__: no eye trackers found!")
self.LEFT_EYE = 0
self.RIGHT_EYE = 1
self.BINOCULAR = 2
self.eye_used = 0 # 0=left, 1=right, 2=binocular
# calibration and validation points
lb = 0.1 # left bound
xc = 0.5 # horizontal center
rb = 0.9 # right bound
ub = 0.1 # upper bound
yc = 0.5 # vertical center
bb = 0.9 # bottom bound
self.points_to_calibrate = [self._norm_2_px(p) for p in [(lb, ub), (xc,ub), (rb, ub), (lb,yc), (xc, yc),(rb,yc), (lb, bb),(xc,bb),(rb, bb)]]
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
self.screensize = settings.SCREENSIZE # display size in cm
self.pixpercm = (self.disp.dispsize[0] / float(self.screensize[0]) + self.disp.dispsize[1] / float(self.screensize[1])) / 2.0
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = self._deg2pix(self.screendist, self.errdist, self.pixpercm)
self.event_data = []
self.t0 = None
self._write_enabled = True
self.datafile = open("{0}_TOBII_output.tsv".format(logfile), 'w')
# initiation report
self.datafile.write("pygaze initiation report start\n")
self.datafile.write("display resolution: %sx%s\n" % (self.disp.dispsize[0], self.disp.dispsize[1]))
self.datafile.write("display size in cm: %sx%s\n" % (self.screensize[0], self.screensize[1]))
self.datafile.write("fixation threshold: %s degrees\n" % self.fixtresh)
self.datafile.write("speed threshold: %s degrees/second\n" % self.spdtresh)
self.datafile.write("acceleration threshold: %s degrees/second**2\n" % self.accthresh)
self.datafile.write("pygaze initiation report end\n")
def _norm_2_px(self, normalized_point):
return (round(normalized_point[0] * self.disp.dispsize[0], 0), round(normalized_point[1] * self.disp.dispsize[1], 0))
def _px_2_norm(self, pixelized_point):
return (pixelized_point[0] / self.disp.dispsize[0], pixelized_point[1] / self.disp.dispsize[1])
def _mean(self, array):
if array:
a = [s for s in array if s is not None]
return sum(a) / float(len(a))
def _deg2pix(self, cmdist, angle, pixpercm):
return pixpercm * math.tan(math.radians(angle)) * float(cmdist)
def log_var(self, var, val):
"""Writes a variable to the log file
arguments
var -- variable name
val -- variable value
returns
Nothing -- uses native log function to include a line
in the log file in a "var NAME VALUE" layout
"""
self.log("var %s %s" % (var, val))
def set_eye_used(self):
"""Logs the eye_used variable, based on which eye was specified.
arguments
None
returns
Nothing -- logs which eye is used by calling self.log_var, e.g.
self.log_var("eye_used", "right")
"""
if self.eye_used == self.BINOCULAR:
self.log_var("eye_used", "binocular")
elif self.eye_used == self.RIGHT_EYE:
self.log_var("eye_used", "right")
else:
self.log_var("eye_used", "left")
def is_valid_sample(self, sample):
"""Checks if the sample provided is valid, based on Tobii specific
criteria (for internal use)
arguments
sample -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
return sample != (-1, -1)
def _on_gaze_data(self, gaze_data):
self.gaze.append(gaze_data)
if self._write_enabled:
self._write_sample(gaze_data)
def start_recording(self):
"""Starts recording eye position
arguments
None
returns
None -- sets self.recording to True when recording is
successfully started
"""
if not self.t0 and self._write_enabled:
self.t0 = tr.get_system_time_stamp()
self._write_header()
if self.recording:
print("WARNING! libtobii.TobiiProTracker.start_recording: Recording already started!")
self.gaze = []
else:
self.gaze = []
self.eyetracker.subscribe_to(tr.EYETRACKER_GAZE_DATA, self._on_gaze_data, as_dictionary=True)
time.sleep(1)
self.recording = True
def stop_recording(self):
"""Stop recording eye position
arguments
None
returns
Nothing -- sets self.recording to False when recording is
successfully started
"""
if self.recording:
self.eyetracker.unsubscribe_from(tr.EYETRACKER_GAZE_DATA)
self.recording = False
self.event_data = []
else:
print("WARNING! libtobii.TobiiProTracker.stop_recording: A recording has not been started!")
def sample(self):
"""Returns newest available gaze position
The gaze position is relative to the self.eye_used currently selected.
If both eyes are selected, the gaze position is averaged from the data of both eyes.
arguments
None
returns
sample -- an (x,y) tuple or a (-1,-1) on an error
"""
gaze_sample = copy.copy(self.gaze[-1])
if self.eye_used == self.LEFT_EYE and gaze_sample["left_gaze_point_validity"]:
return self._norm_2_px(gaze_sample["left_gaze_point_on_display_area"])
if self.eye_used == self.RIGHT_EYE and gaze_sample["right_gaze_point_validity"]:
return self._norm_2_px(gaze_sample["right_gaze_point_on_display_area"])
if self.eye_used == self.BINOCULAR:
if gaze_sample["left_gaze_point_validity"] and gaze_sample["right_gaze_point_validity"]:
left_sample = self._norm_2_px(gaze_sample["left_gaze_point_on_display_area"])
right_sample = self._norm_2_px(gaze_sample["right_gaze_point_on_display_area"])
return (self._mean([left_sample[0], right_sample[0]]), self._mean([left_sample[1], right_sample[1]]))
if gaze_sample["left_gaze_point_validity"]:
return self._norm_2_px(gaze_sample["left_gaze_point_on_display_area"])
if gaze_sample["right_gaze_point_validity"]:
return self._norm_2_px(gaze_sample["right_gaze_point_on_display_area"])
return (-1, -1)
def pupil_size(self):
"""Returns newest available pupil size
arguments
None
returns
pupilsize -- a float if only eye is selected or only one eye has valid data.
-- a tuple with two floats if both eyes are selected.
-- -1 if there is no valid pupil data available.
"""
if self.gaze:
gaze_sample = copy.copy(self.gaze[-1])
if self.eye_used == self.BINOCULAR:
pupil_data = [-1, -1]
if gaze_sample["left_pupil_validity"]:
pupil_data[0] = gaze_sample["left_pupil_diameter"]
if gaze_sample["right_pupil_validity"]:
pupil_data[1] = gaze_sample["right_pupil_diameter"]
return tuple(pupil_data)
if self.eye_used == self.LEFT_EYE and gaze_sample["left_pupil_validity"]:
return gaze_sample["left_pupil_diameter"]
if self.eye_used == self.RIGHT_EYE and gaze_sample["right_pupil_validity"]:
return gaze_sample["right_pupil_diameter"]
return -1
def ReduceBall (self,point,facteur,colour):
self.showPoint(point,colour,facteur)
for i in range (0,200,3):
self.screen.clear()
self.screen.draw_circle(colour=colour, pos=point, r=int(self.disp.dispsize[0] / (facteur+i)), pw=5, fill=True)
self.disp.fill(self.screen)
self.disp.show()
def showPoint( self,point,colour,facteur):
self.screen.clear()
self.screen.draw_circle(colour=colour, pos=point, r=int(self.disp.dispsize[0] / facteur), pw=5, fill=True)
self.disp.fill(self.screen)
self.disp.show()
def calibrate(self, calibrate=True, validate=True):
"""Calibrates the eye tracker.
arguments
None
keyword arguments
calibrate -- Boolean indicating if calibration should be
performed (default = True).
validate -- Boolean indicating if validation should be performed
(default = True).
returns
success -- returns True if calibration succeeded, or False if
not; in addition a calibration log is added to the
log file and some properties are updated (i.e. the
thresholds for detection algorithms)
"""
self._write_enabled = False
self.start_recording()
self.screen.set_background_colour(colour=(0, 0, 0))
if calibrate:
origin = (int(self.disp.dispsize[0] / 4), int(self.disp.dispsize[1] / 4))
size = (int(2 * self.disp.dispsize[0] / 4), int(2 * self.disp.dispsize[1] / 4))
while not self.kb.get_key(keylist=['space'], flush=False)[0]:
gaze_sample = copy.copy(self.gaze[-1])
self.screen.clear()
validity_colour = (255, 0, 0)
if gaze_sample['right_gaze_origin_validity'] and gaze_sample['left_gaze_origin_validity']:
left_validity = 0.15 < gaze_sample['left_gaze_origin_in_trackbox_coordinate_system'][2] < 0.85
right_validity = 0.15 < gaze_sample['right_gaze_origin_in_trackbox_coordinate_system'][2] < 0.85
if left_validity and right_validity:
validity_colour = (0, 255, 0)
self.screen.draw_text(text="When correctly positioned press \'space\' to start the calibration.", pos=(int(self.disp.dispsize[0] / 2), int(self.disp.dispsize[1] * 0.1)), colour=(255, 255, 255), fontsize=20)
self.screen.draw_line(colour=validity_colour, spos=origin, epos=(origin[0] + size[0], origin[1]), pw=1)
self.screen.draw_line(colour=validity_colour, spos=origin, epos=(origin[0], origin[1] + size[1]), pw=1)
self.screen.draw_line(colour=validity_colour, spos=(origin[0], origin[1] + size[1]), epos=(origin[0] + size[0], origin[1] + size[1]), pw=1)
self.screen.draw_line(colour=validity_colour, spos=(origin[0] + size[0], origin[1] + size[1]), epos=(origin[0] + size[0], origin[1]), pw=1)
right_eye, left_eye, distance = None, None, []
if gaze_sample['right_gaze_origin_validity']:
distance.append(round(gaze_sample['right_gaze_origin_in_user_coordinate_system'][2] / 10, 1))
right_eye = ((1 - gaze_sample['right_gaze_origin_in_trackbox_coordinate_system'][0]) * size[0] + origin[0],
gaze_sample['right_gaze_origin_in_trackbox_coordinate_system'][1] * size[1] + origin[1])
self.screen.draw_circle(colour=validity_colour, pos=right_eye, r=int(self.disp.dispsize[0] / 100), pw=5, fill=True)
if gaze_sample['left_gaze_origin_validity']:
distance.append(round(gaze_sample['left_gaze_origin_in_user_coordinate_system'][2] / 10, 1))
left_eye = ((1 - gaze_sample['left_gaze_origin_in_trackbox_coordinate_system'][0]) * size[0] + origin[0],
gaze_sample['left_gaze_origin_in_trackbox_coordinate_system'][1] * size[1] + origin[1])
self.screen.draw_circle(colour=validity_colour, pos=left_eye, r=int(self.disp.dispsize[0] / 100), pw=5, fill=True)
self.screen.draw_text(text="Current distance to the eye tracker: {0} cm.".format(self._mean(distance)), pos=(int(self.disp.dispsize[0] / 2), int(self.disp.dispsize[1] * 0.9)), colour=(255, 255, 255), fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# # # # # #
# # calibration
if not self.eyetracker:
print("WARNING! libtobii.TobiiProTracker.calibrate: no eye trackers found for the calibration!")
self.stop_recording()
return False
calibration = tr.ScreenBasedCalibration(self.eyetracker)
calibrating = True
while calibrating:
calibration.enter_calibration_mode()
for point in self.points_to_calibrate:
self.screen.clear()
# CDP : Changement couleur
#self.screen.draw_circle(colour='yellow', pos=point, r=int(self.disp.dispsize[0] / 100.0), pw=5, fill=True)
#self.screen.draw_circle(colour=(255, 0, 0), pos=point, r=int(self.disp.dispsize[0] / 400.0), pw=5, fill=True)
#self.disp.fill(self.screen)
#self.disp.show()
# Wait a little for user to focus.
# CDP : Ajout sasie clavier
#clock.pause(1000)
self.ReduceBall(point,30,'yellow')
pressed_key = self.kb.get_key(keylist=['space', 'r'], flush=True, timeout=None)
normalized_point = self._px_2_norm(point)
if calibration.collect_data(normalized_point[0], normalized_point[1]) != tr.CALIBRATION_STATUS_SUCCESS:
# Try again if it didn't go well the first time.
# Not all eye tracker models will fail at this point, but instead fail on ComputeAndApply.
calibration.collect_data(normalized_point[0], normalized_point[1])
self.screen.clear()
self.screen.draw_text("Calculating calibration result....", colour=(255, 255, 255), fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
calibration_result = calibration.compute_and_apply()
calibration.leave_calibration_mode()
print "Compute and apply returned {0} and collected at {1} points.".\
format(calibration_result.status, len(calibration_result.calibration_points))
if calibration_result.status != tr.CALIBRATION_STATUS_SUCCESS:
self.stop_recording()
print("WARNING! libtobii.TobiiProTracker.calibrate: Calibration was unsuccessful!")
return False
self.screen.clear()
for point in calibration_result.calibration_points:
self.screen.draw_circle(colour=(255, 255, 255), pos=self._norm_2_px(point.position_on_display_area), r=self.disp.dispsize[0] / 200, pw=1, fill=False)
for sample in point.calibration_samples:
if sample.left_eye.validity == tr.VALIDITY_VALID_AND_USED:
self.screen.draw_circle(colour=(255, 0, 0), pos=self._norm_2_px(sample.left_eye.position_on_display_area), r=self.disp.dispsize[0] / 450, pw=self.disp.dispsize[0] / 450, fill=False)
self.screen.draw_line(colour=(255, 0, 0), spos=self._norm_2_px(point.position_on_display_area), epos=self._norm_2_px(sample.left_eye.position_on_display_area), pw=1)
if sample.right_eye.validity == tr.VALIDITY_VALID_AND_USED:
self.screen.draw_circle(colour=(0, 0, 255), pos=self._norm_2_px(sample.right_eye.position_on_display_area), r=self.disp.dispsize[0] / 450, pw=self.disp.dispsize[0] / 450, fill=False)
self.screen.draw_line(colour=(0, 0, 255), spos=self._norm_2_px(point.position_on_display_area), epos=self._norm_2_px(sample.right_eye.position_on_display_area), pw=1)
self.screen.draw_text("Press the \'R\' key to recalibrate or \'Space\' to continue....", pos=(0.5 * self.disp.dispsize[0], 0.95 * self.disp.dispsize[1]), colour=(255, 255, 255), fontsize=20)
self.screen.draw_text("Left Eye", pos=(0.5 * self.disp.dispsize[0], 0.01 * self.disp.dispsize[1]), colour=(255, 0, 0), fontsize=20)
self.screen.draw_text("Right Eye", pos=(0.5 * self.disp.dispsize[0], 0.03 * self.disp.dispsize[1]), colour=(0, 0, 255), fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
pressed_key = self.kb.get_key(keylist=['space', 'r'], flush=True, timeout=None)
if pressed_key[0] == 'space':
calibrating = False
if validate:
# # # show menu
self.screen.clear()
self.screen.draw_text(text="Press space to start validation", colour=(255, 255, 255), fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# # # wait for spacepress
self.kb.get_key(keylist=['space'], flush=True, timeout=None)
# # # # # #
# # validation
# # # arrays for data storage
lxacc, lyacc, rxacc, ryacc = [], [], [], []
# # loop through all calibration positions
for pos in self.points_to_calibrate:
# show validation point
self.screen.clear()
self.screen.draw_fixation(fixtype='dot', pos=pos, colour=(255, 255, 255))
self.disp.fill(self.screen)
self.disp.show()
# allow user some time to gaze at dot
clock.pause(1000)
lxsamples, lysamples, rxsamples, rysamples = [], [], [], []
for sample in self.gaze:
if sample["left_gaze_point_validity"]:
gaze_point = self._norm_2_px(sample["left_gaze_point_on_display_area"])
lxsamples.append(abs(gaze_point[0] - pos[0]))
lysamples.append(abs(gaze_point[1] - pos[1]))
if sample["right_gaze_point_validity"]:
gaze_point = self._norm_2_px(sample["right_gaze_point_on_display_area"])
rxsamples.append(abs(gaze_point[0] - pos[0]))
rysamples.append(abs(gaze_point[1] - pos[1]))
# calculate mean deviation
lxacc.append(self._mean(lxsamples))
lyacc.append(self._mean(lysamples))
rxacc.append(self._mean(rxsamples))
ryacc.append(self._mean(rysamples))
# wait for a bit to slow down validation process a bit
clock.pause(1000)
# calculate mean accuracy
self.pxaccuracy = [(self._mean(lxacc), self._mean(lyacc)), (self._mean(rxacc), self._mean(ryacc))]
# sample rate
# calculate intersample times
timestamps = []
gaze_samples = copy.copy(self.gaze)
for i in xrange(0, len(gaze_samples) - 1):
timestamps.append((gaze_samples[i + 1]['system_time_stamp'] - gaze_samples[i]['system_time_stamp']) / 1000.0)
# mean intersample time
self.sampletime = self._mean(timestamps)
self.samplerate = int(1000.0 / self.sampletime)
# # # # # #
# # RMS noise
# # present instructions
self.screen.clear()
self.screen.draw_text(text="Noise calibration: please look at the dot\n\n(press space to start)", pos=(self.disp.dispsize[0] / 2, int(self.disp.dispsize[1] * 0.2)), colour=(255, 255, 255), fontsize=20)
self.screen.draw_fixation(fixtype='dot', colour=(255, 255, 255))
self.disp.fill(self.screen)
self.disp.show()
# # wait for spacepress
self.kb.get_key(keylist=['space'], flush=True, timeout=None)
# # show fixation
self.screen.draw_fixation(fixtype='dot', colour=(255, 255, 255))
self.disp.fill(self.screen)
self.disp.show()
self.screen.clear()
# # wait for a bit, to allow participant to fixate
clock.pause(500)
# # get samples
sl = [self.sample()] # samplelist, prefilled with 1 sample to prevent sl[-1] from producing an error; first sample will be ignored for RMS calculation
t0 = clock.get_time() # starting time
while clock.get_time() - t0 < 1000:
s = self.sample() # sample
if s != sl[-1] and self.is_valid_sample(s) and s != (0, 0):
sl.append(s)
# # calculate RMS noise
Xvar, Yvar = [], []
for i in xrange(2, len(sl)):
Xvar.append((sl[i][0] - sl[i - 1][0])**2)
Yvar.append((sl[i][1] - sl[i - 1][1])**2)
XRMS = (self._mean(Xvar))**0.5
YRMS = (self._mean(Yvar))**0.5
self.pxdsttresh = (XRMS, YRMS)
# # # # # # #
# # # calibration report
# # # # recalculate thresholds (degrees to pixels)
self.pxfixtresh = self._deg2pix(self.screendist, self.fixtresh, self.pixpercm)
self.pxspdtresh = self._deg2pix(self.screendist, self.spdtresh / 1000.0, self.pixpercm) # in pixels per millisecons
self.pxacctresh = self._deg2pix(self.screendist, self.accthresh / 1000.0, self.pixpercm) # in pixels per millisecond**2
data_to_write = ''
data_to_write += "pygaze calibration report start\n"
data_to_write += "samplerate: %s Hz\n" % self.samplerate
data_to_write += "sampletime: %s ms\n" % self.sampletime
data_to_write += "accuracy (in pixels): LX=%s, LY=%s, RX=%s, RY=%s\n" % (self.pxaccuracy[0][0], self.pxaccuracy[0][1], self.pxaccuracy[1][0], self.pxaccuracy[1][1])
data_to_write += "precision (RMS noise in pixels): X=%s, Y=%s\n" % (self.pxdsttresh[0], self.pxdsttresh[1])
data_to_write += "distance between participant and display: %s cm\n" % self.screendist
data_to_write += "fixation threshold: %s pixels\n" % self.pxfixtresh
data_to_write += "speed threshold: %s pixels/ms\n" % self.pxspdtresh
data_to_write += "accuracy threshold: %s pixels/ms**2\n" % self.pxacctresh
data_to_write += "pygaze calibration report end\n"
# # # # write report to log
#self.datafile.write(data_to_write)
self.screen.clear()
self.screen.draw_text(text=data_to_write, pos=(self.disp.dispsize[0] / 2, int(self.disp.dispsize[1] / 2)), colour=(255, 255, 255), fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
self.kb.get_key(keylist=['space'], flush=True, timeout=None)
self.stop_recording()
self._write_enabled = True
return True
def fix_triggered_drift_correction(self, pos=None, min_samples=10, max_dev=60, reset_threshold=30):
"""Performs a fixation triggered drift correction by collecting
a number of samples and calculating the average distance from the
fixation position
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
min_samples -- minimal amount of samples after which an
average deviation is calculated (default = 10)
max_dev -- maximal deviation from fixation in pixels
(default = 60)
reset_threshold -- if the horizontal or vertical distance in
pixels between two consecutive samples is
larger than this threshold, the sample
collection is reset (default = 30)
returns
checked -- Boolean indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos is None:
pos = self.disp.dispsize[0] / 2, self.disp.dispsize[1] / 2
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key()[0] in ['escape', 'q']:
print("libtobii.TobiiTracker.fix_triggered_drift_correction: 'q' or 'escape' pressed")
return self.calibrate(calibrate=True, validate=True)
# collect a sample
x, y = self.sample()
if len(lx) == 0 or (x, y) != (lx[-1], ly[-1]):
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
if len(lx) == min_samples:
avg_x = self._mean(lx)
avg_y = self._mean(ly)
d = ((avg_x - pos[0]) ** 2 + (avg_y - pos[1]) ** 2)**0.5
if d < max_dev:
if stoprec:
self.stop_recording()
return True
else:
lx = []
ly = []
if stoprec:
self.stop_recording()
def drift_correction(self, pos=None, fix_triggered=False):
"""Performs a drift check
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
fix_triggered -- Boolean indicating if drift check should be
performed based on gaze position (fix_triggered
= True) or on spacepress (fix_triggered =
False) (default = False)
returns
checked -- Boolean indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
if pos is None:
pos = self.disp.dispsize[0] / 2, self.disp.dispsize[1] / 2
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
result = False
pressed = False
while not pressed:
pressed, presstime = self.kb.get_key()
if pressed:
if pressed == 'escape' or pressed == 'q':
print("libtobii.TobiiProTracker.drift_correction: 'q' or 'escape' pressed")
return self.calibrate(calibrate=True, validate=True)
gazepos = self.sample()
if ((gazepos[0] - pos[0])**2 + (gazepos[1] - pos[1])**2)**0.5 < self.pxerrdist:
result = True
if stoprec:
self.stop_recording()
return result
def wait_for_fixation_start(self):
"""Returns starting time and position when a fixation is started;
function assumes a 'fixation' has started when gaze position
remains reasonably stable (i.e. when most deviant samples are
within self.pxfixtresh) for five samples in a row (self.pxfixtresh
is created in self.calibration, based on self.fixtresh, a property
defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# Tobii method
if self.eventdetection == 'native':
# print warning, since Tobii does not have a fixation start
# detection built into their API (only ending)
print("WARNING! 'native' event detection has been selected, \
but Tobii does not offer fixation detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0] - spos[0])**2 + (npos[1] - spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
if stoprec:
self.stop_recording()
# return time and starting position
return t0, spos
def wait_for_fixation_end(self):
"""Returns time and gaze position when a fixation has ended;
function assumes that a 'fixation' has ended when a deviation of
more than self.pxfixtresh from the initial fixation position has
been detected (self.pxfixtresh is created in self.calibration,
based on self.fixtresh, a property defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# Tobii method
if self.eventdetection == 'native':
# print warning, since Tobii does not have a fixation detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but Tobii does not offer fixation detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0] - spos[0])**2 + (npos[1] - spos[1])**2 > self.pxfixtresh**2:
# break loop if deviation is too high
break
if stoprec:
self.stop_recording()
return clock.get_time(), spos
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a saccade is
started; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos -- endtime in milliseconds (from expbegintime);
startpos is an (x,y) gaze position tuple
"""
# # # # #
# Tobii method
if self.eventdetection == 'native':
# print warning, since Tobii does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but Tobii does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0] - prevpos[0]
sy = newpos[1] - prevpos[1]
if (sx / self.pxdsttresh[0])**2 + (sy / self.pxdsttresh[1])**2 > self.weightdist: # weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
if stoprec:
self.stop_recording()
return stime, spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a saccade is
ended; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos, endpos -- endtime in milliseconds (from
expbegintime); startpos and endpos
are (x,y) gaze position tuples
"""
# # # # #
# Tobii method
if self.eventdetection == 'native':
# print warning, since Tobii does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but Tobii does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0] - spos[0])**2 + (prevpos[1] - spos[1])**2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1 - t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0] - prevpos[0])**2 + (newpos[1] - prevpos[1])**2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1 * self.pxacctresh and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
if stoprec:
self.stop_recording()
return etime, spos, epos
def wait_for_blink_start(self):
"""Waits for a blink start and returns the blink starting time
arguments
None
returns
timestamp -- blink starting time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# Tobii method
if self.eventdetection == 'native':
# print warning, since Tobii does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but Tobii does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed BLINKTHRESH
if clock.get_time() - t0 >= self.blinkthresh:
if stoprec:
self.stop_recording()
# return timestamp of blink start
return t0
def wait_for_blink_end(self):
"""Waits for a blink end and returns the blink ending time
arguments
None
returns
timestamp -- blink ending time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# Tobii method
if self.eventdetection == 'native':
# print warning, since Tobii does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but Tobii does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
# start recording if recording has not yet started
if not self.recording:
self.start_recording()
stoprec = True
else:
stoprec = False
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
if stoprec:
self.stop_recording()
# return timestamp of blink end
return clock.get_time()
def log(self, msg):
"""Writes a message to the log file
arguments
msg -- a string to include in the log file
returns
Nothing -- uses native log function to include a line
in the log file
"""
t = tr.get_system_time_stamp()
if not self.t0:
self.t0 = t
self._write_header()
self.datafile.write('%.4f\t%s\n' % ((t - self.t0) / 1000.0, msg))
self._flush_to_file()
def _flush_to_file(self):
# write data to disk
self.datafile.flush() # internal buffer to RAM
os.fsync(self.datafile.fileno()) # RAM file cache to disk
def _write_header(self):
# write header
self.datafile.write('\t'.join(['TimeStamp',
'Event',
'GazePointXLeft',
'GazePointYLeft',
'ValidityLeft',
'GazePointXRight',
'GazePointYRight',
'ValidityRight',
'GazePointX',
'GazePointY',
'PupilSizeLeft',
'PupilValidityLeft',
'PupilSizeRight',
'PupilValidityRight']) + '\n')
self._flush_to_file()
def _write_sample(self, sample):
# write timestamp and gaze position for both eyes to the datafile
left_gaze_point = self._norm_2_px(sample['left_gaze_point_on_display_area']) if sample['left_gaze_point_validity'] else (-1, -1)
right_gaze_point = self._norm_2_px(sample['right_gaze_point_on_display_area']) if sample['right_gaze_point_validity'] else (-1, -1)
self.datafile.write('%.4f\t\t%d\t%d\t%d\t%d\t%d\t%d' % (
(sample['system_time_stamp'] - self.t0) / 1000.0,
left_gaze_point[0],
left_gaze_point[1],
sample['left_gaze_point_validity'],
right_gaze_point[0],
right_gaze_point[1],
sample['right_gaze_point_validity']))
# if no correct sample is available, data is missing
if not (sample['left_gaze_point_validity'] or sample['right_gaze_point_validity']): # not detected
ave = (-1.0, -1.0)
# if the right sample is unavailable, use left sample
elif not sample['right_gaze_point_validity']:
ave = left_gaze_point
# if the left sample is unavailable, use right sample
elif not sample['left_gaze_point_validity']:
ave = right_gaze_point
# if we have both samples, use both samples
else:
ave = (int(round((left_gaze_point[0] + right_gaze_point[0]) / 2.0, 0)),
(int(round(left_gaze_point[1] + right_gaze_point[1]) / 2.0)))
# write gaze position to the datafile, based on the selected sample(s)
self.datafile.write('\t%d\t%d' % ave)
left_pupil = sample['left_pupil_diameter'] if sample['left_pupil_validity'] else -1
right_pupil = sample['right_pupil_diameter'] if sample['right_pupil_validity'] else -1
self.datafile.write('\t%.4f\t%d\t%.4f\t%d' % (left_pupil,
sample['left_pupil_validity'],
right_pupil,
sample['right_pupil_validity']))
self.datafile.write('\n')
self._flush_to_file()
def close(self):
"""Closes the currently used log file.
arguments
None
returns
None -- closes the log file.
"""
self.datafile.close()
# PyGaze from constants import * from pygaze.display import Display from pygaze.screen import Screen from pygaze.eyetracker import EyeTracker from pygaze.keyboard import Keyboard from pygaze.libtime import clock # # # # # # SETUP # visuals disp = Display() scr = Screen() # input tracker = EyeTracker(disp) kb = Keyboard(keylist=None, timeout=None) # calibrate tracker.calibrate() # starting screen scr.clear() scr.draw_text(text="Press Space to start") disp.fill(scr) disp.show() kb.get_key(keylist=['space'], timeout=None, flush=True)
def __init__(self, display, tracker):
"""
Constructor.
Arguments:
display -- A PyGaze Display object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.display = display
self.screen = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=1)
if DISPTYPE == 'pygame':
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
#if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), \
'__eyelink__.jpg')
# drawing properties
self.xc = self.display.dispsize[0]/2
self.yc = self.display.dispsize[1]/2
self.ld = 40 # line distance
# menu
self.menuscreen = Screen(disptype=DISPTYPE, mousevisible=False)
self.menuscreen.draw_text(text="== Eyelink calibration menu ==", pos= \
(self.xc,self.yc-5*self.ld), center=True, font='mono', fontsize= \
12, antialias=True)
self.menuscreen.draw_text(text="Press C to calibrate", pos=(self.xc, \
self.yc-3*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press V to validate", pos=(self.xc, \
self.yc-2*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press A to auto-threshold", pos=( \
self.xc,self.yc-1*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press Enter to show camera image", \
pos=(self.xc,self.yc+1*self.ld), center=True, font='mono', \
fontsize=12, antialias=True)
self.menuscreen.draw_text(text= \
"(then change between images using the arrow keys)", pos=(self.xc, \
self.yc+2*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
self.menuscreen.draw_text(text="Press Q to exit menu", pos=(self.xc, \
self.yc+5*self.ld), center=True, font='mono', fontsize=12, \
antialias=True)
# beeps
self.__target_beep__ = Sound(osc='sine', freq=440, length=50, attack= \
0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc='sine', freq=880, length=200, \
attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc='sine', freq=220, length=200, \
attack=0, decay=0, soundfile=None)
# further properties
self.state = None
self.imagebuffer = array.array('l')
self.pal = None
self.size = (0,0)
self.set_tracker(tracker)
self.last_mouse_state = -1
class AleaTracker(BaseEyeTracker):
"""A class for AleaTracker objects"""
def __init__(self, display, logfile=settings.LOGFILE, \
alea_key=settings.ALEAKEY, \
animated_calibration=settings.ALEAANIMATEDCALIBRATION, \
eventdetection=settings.EVENTDETECTION, \
saccade_velocity_threshold=35, \
saccade_acceleration_threshold=9500, \
blink_threshold=settings.BLINKTHRESH, \
**args):
"""Initializes the AleaTracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
logfile -- logfile name (string value); note that this is the
name for the eye data log file (default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, AleaTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = self.disp.dispsize # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# show a message
self.screen.clear()
self.screen.draw_text(
text="Initialising the eye tracker, please wait...", fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# output file properties
self.outputfile = logfile + '.tsv'
# calibration properties
self.animated_calibration = animated_calibration == True
# eye tracker properties
self.connected = False
self.recording = False
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = 30 # initial error in pixels
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# connect to the tracker
self.alea = OGAleaTracker(alea_key, file_path=self.outputfile)
# get info on the sample rate
# TODO: Compute after streaming some samples?
self.samplerate = 60.0
self.sampletime = 1000.0 / self.samplerate
# initiation report
self.log("pygaze initiation report start")
self.log("display resolution: {}x{}".format( \
self.dispsize[0], self.dispsize[1]))
self.log("display size in cm: {}x{}".format( \
self.screensize[0], self.screensize[1]))
self.log("samplerate: {} Hz".format(self.samplerate))
self.log("sampletime: {} ms".format(self.sampletime))
self.log("fixation threshold: {} degrees".format(self.fixtresh))
self.log("speed threshold: {} degrees/second".format(self.spdtresh))
self.log("acceleration threshold: {} degrees/second**2".format( \
self.accthresh))
self.log("pygaze initiation report end")
def calibrate(self, animated=None, skip_bad_points=False):
"""Calibrates the eye tracking system
arguments
None
keyword arguments
animated -- bool. Set to True to show a parrot animation instead
of calibration dots, or False to use standard points.
Set to None to use default option.
skip_bad_points -- bool. Intelligaze will skip difficult points
when set to True. (Default = False)
returns
success -- returns True if calibration succeeded, or False if
not; in addition a calibration log is added to the
log file and some properties are updated (i.e. the
thresholds for detection algorithms)
"""
# Process animated keyword argument.
if animated is None:
animated = self.animated_calibration
if animated:
img = "ANIMATION:PARROT"
else:
img = ""
# Show a message.
self.screen.clear()
self.screen.draw_text(text="Running calibration in the foreground...",
fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# CALIBRATION
# Re-run the calibration until it was approved by the user.
quited = False
calibration_approved = False
while not calibration_approved:
# Wait for the calibration to finish.
status, improve = self.alea.calibrate(image=img, \
skip_bad_points=skip_bad_points)
# Construct a message string.
if status == 0:
calib_str = "Calibration completed!"
else:
calib_str = "Calibration failed!"
if improve:
calib_str += "\n\nWARNING: IntelliGaze recommends repeating the calibration to improve accuracy."
calib_str += "\n\n\nPress R to retry, or Space to continue."
# Show calibration results.
self.screen.clear()
self.screen.draw_text(text=calib_str, fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# Wait for user input.
key = None
while key not in ["r", "Space", "space", "q"]:
key, keytime = self.kb.get_key(keylist=['q', 'r', 'space'],
timeout=None,
flush=True)
# Process key press.
if key in ["q", "Space", "space"]:
calibration_approved = True
if key == "q":
quited = True
# Calibration failed if the user quited.
if quited:
return False
# NOISE CALIBRATION
# Present noise calibration instructions.
self.screen.clear()
self.screen.draw_text(
text="Noise calibration. Please look at the dot, and press any key to start.",
fontsize=20, \
pos=(int(self.dispsize[0]/2),int(self.dispsize[1]*0.3)))
self.screen.draw_fixation(fixtype="dot")
self.disp.fill(self.screen)
self.disp.show()
# Wait for a keypress.
key, keytime = self.kb.get_key(keylist=None, timeout=None, \
flush=True)
# Start with empty lists.
err = {'LX': [], 'LY': [], 'RX': [], 'RY': []}
var = {'LX': [], 'LY': [], 'RX': [], 'RY': []}
# Start streaming data so that samples can be obtained.
self.start_recording()
self.log("noise_calibration_start")
# Present a central fixation.
x = int(float(self.dispsize[0]) / 2.0)
y = int(float(self.dispsize[1]) / 2.0)
self.screen.clear()
self.screen.draw_fixation(fixtype="dot", pos=(x, y))
self.disp.fill(self.screen)
t0 = self.disp.show()
# Collect at least 10 samples, and wait for at least 1 second.
i = 0
while (i < 10) or (clock.get_time() - t0 < 1000):
# Get new sample.
gx, gy = self.sample()
if (gx > 0) and (gy > 0):
i += 1
err["LX"].append(abs(float(x) - float(gx)))
err["LY"].append(abs(float(y) - float(gy)))
err["RX"].append(abs(float(x) - float(gx)))
err["RY"].append(abs(float(y) - float(gy)))
for k in var.keys():
var[k].append(err[k][-1]**2)
clock.pause(int(self.sampletime))
# Stop streaming.
self.log("noise_calibration_stop")
self.stop_recording()
# Compute the RMS noise for the calibration points.
xnoise = (math.sqrt(sum(var['LX']) / float(len(var['LX']))) + \
math.sqrt(sum(var['RX']) / float(len(var['RX'])))) / 2.0
ynoise = (math.sqrt(sum(var['LY']) / float(len(var['LY']))) + \
math.sqrt(sum(var['RY']) / float(len(var['RY'])))) / 2.0
self.pxdsttresh = (xnoise, ynoise)
# AFTERMATH
# store some variables
pixpercm = (self.dispsize[0] / float(self.screensize[0]) + \
self.dispsize[1]/float(self.screensize[1])) / 2
screendist = settings.SCREENDIST
# calculate thresholds based on tracker settings
self.accuracy = ( \
(pix2deg(screendist, sum(err['LX']) / float(len(err['LX'])), pixpercm), \
pix2deg(screendist, sum(err['LY']) / float(len(err['LY'])), pixpercm)), \
(pix2deg(screendist, sum(err['RX']) / float(len(err['RX'])), pixpercm), \
pix2deg(screendist, sum(err['RY']) / float(len(err['RY'])), pixpercm)))
self.pxerrdist = deg2pix(screendist, self.errdist, pixpercm)
self.pxfixtresh = deg2pix(screendist, self.fixtresh, pixpercm)
self.pxaccuracy = ( \
(sum(err['LX']) / float(len(err['LX'])), \
sum(err['LY']) / float(len(err['LY']))), \
(sum(err['RX']) / float(len(err['RX'])), \
sum(err['RY']) / float(len(err['RY']))))
self.pxspdtresh = deg2pix(screendist, self.spdtresh / 1000.0,
pixpercm) # in pixels per millisecond
self.pxacctresh = deg2pix(screendist, self.accthresh / 1000.0,
pixpercm) # in pixels per millisecond**2
# calibration report
self.log("pygaze calibration report start")
self.log("accuracy (degrees): LX={}, LY={}, RX={}, RY={}".format( \
self.accuracy[0][0], self.accuracy[0][1], self.accuracy[1][0], \
self.accuracy[1][1]))
self.log("accuracy (in pixels): LX={}, LY={}, RX={}, RY={}".format( \
self.pxaccuracy[0][0], self.pxaccuracy[0][1], \
self.pxaccuracy[1][0], self.pxaccuracy[1][1]))
self.log("precision (RMS noise in pixels): X={}, Y={}".format( \
self.pxdsttresh[0],self.pxdsttresh[1]))
self.log("distance between participant and display: {} cm".format( \
screendist))
self.log("fixation threshold: {} pixels".format(self.pxfixtresh))
self.log("speed threshold: {} pixels/ms".format(self.pxspdtresh))
self.log("acceleration threshold: {} pixels/ms**2".format( \
self.pxacctresh))
self.log("pygaze calibration report end")
return True
def close(self):
"""Neatly close connection to tracker
arguments
None
returns
Nothing -- saves data and sets self.connected to False
"""
# close connection
self.alea.close()
self.connected = False
def connected(self):
"""Checks if the tracker is connected
arguments
None
returns
connected -- True if connection is established, False if not;
sets self.connected to the same value
"""
return self.connected
def drift_correction(self, pos=None, fix_triggered=False):
"""Performs a drift check
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
fix_triggered -- Boolean indicating if drift check should be
performed based on gaze position (fix_triggered
= True) or on spacepress (fix_triggered =
False) (default = False)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos == None:
pos = (int(self.dispsize[0] / 2), int(self.dispsize[1] / 2))
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
self.draw_drift_correction_target(pos[0], pos[1])
pressed = False
while not pressed:
pressed, presstime = self.kb.get_key()
if pressed:
if pressed in ["Escape", "escape", "q"]:
print(
"libalea.AleaTracker.drift_correction: 'q' or 'escape' pressed"
)
return self.calibrate()
gazepos = self.sample()
if ((gazepos[0] - pos[0])**2 +
(gazepos[1] - pos[1])**2)**0.5 < self.pxerrdist:
return True
else:
self.errorbeep.play()
return False
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.screen.clear()
self.screen.draw_fixation(fixtype='dot',
colour=settings.FGC,
pos=(x, y),
pw=0,
diameter=12)
self.disp.fill(self.screen)
self.disp.show()
def draw_calibration_target(self, x, y):
self.draw_drift_correction_target(x, y)
def fix_triggered_drift_correction(self,
pos=None,
min_samples=4,
max_dev=120,
timeout=10000):
"""Performs a fixation triggered drift correction by collecting
a number of samples and calculating the average distance from the
fixation position
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
min_samples -- minimal amount of samples after which a
fixation is accepted (default = 4)
max_dev -- maximal deviation from fixation in pixels
(default = 120)
timeout -- Time in milliseconds until fixation-triggering is
given up on, and calibration is started
(default = 10000)
returns
checked -- Boolean indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos == None:
pos = (int(self.dispsize[0] / 2), int(self.dispsize[1] / 2))
self.draw_drift_correction_target(pos[0], pos[1])
t0 = clock.get_time()
consecutive_count = 0
while consecutive_count < min_samples:
# Get new sample.
x, y = self.sample()
# Ignore empty samples.
if (x is None) or (y is None):
continue
# Measure the distance to the target position.
d = ((x - pos[0])**2 + (y - pos[1])**2)**0.5
# Check whether the distance is below the allowed distance.
if d <= max_dev:
# Increment count.
consecutive_count += 1
else:
# Reset count.
consecutive_count = 0
# Check for a timeout.
if clock.get_time() - t0 > timeout:
print(
"libalea.AleaTracker.fix_triggered_drift_correction: timeout during fixation-triggered drift check"
)
return self.calibrate()
# Pressing escape enters the calibration screen.
if self.kb.get_key()[0] in ["Escape", "escape", "q"]:
print(
"libalea.AleaTracker.fix_triggered_drift_correction: 'q' or 'escape' pressed"
)
return self.calibrate()
return True
def get_eyetracker_clock_async(self):
"""Not supported for AleaTracker (yet)"""
print(
"get_eyetracker_clock_async function not supported for AleaTracker"
)
def log(self, msg):
"""Writes a message to the log file
arguments
ms -- a string to include in the log file
returns
Nothing -- uses native log function of iViewX to include a line
in the log file
"""
self.alea.log(msg)
def prepare_drift_correction(self, pos):
"""Not supported for AleaTracker"""
print(
"prepare_drift_correction function not supported for AleaTracker")
def pupil_size(self):
"""Return pupil size
arguments
None
returns
pupil size -- returns pupil diameter for the eye that is currently
being tracked (as specified by self.eye_used) or -1
when no data is obtainable
"""
# Get the latest sample.
t, x, y, ps = self.alea.sample()
# Invalid data.
if ps == 0:
return -1
# Check if the new pupil size is the same as the previous.
if ps != self.prevps:
# Update the pupil size.
self.prevps = copy.copy(ps)
return self.prevps
def sample(self):
"""Returns newest available gaze position
arguments
None
returns
sample -- an (x,y) tuple or a (-1,-1) on an error
"""
# Get the latest sample.
t, x, y, ps = self.alea.sample()
# Invalid data.
if (x == 0) and (y == 0):
return (-1, -1)
# Combine the x and y coordinates.
s = (int(x), int(y))
# Check if the new sample is the same as the previous.
if s != self.prevsample:
# Update the current sample.
self.prevsample = copy.copy(s)
return self.prevsample
def send_command(self, cmd):
"""Function not supported.
"""
print("send_command function not supported for AleaTracker")
def start_recording(self):
"""Starts recording eye position
arguments
None
returns
Nothing -- sets self.recording to True when recording is
successfully started
"""
self.alea.start_recording()
self.recording = True
def status_msg(self, msg):
"""Not supported for AleaTracker"""
print("status_msg function not supported for AleaTracker")
def stop_recording(self):
"""Stop recording eye position
arguments
None
returns
Nothing -- sets self.recording to False when recording is
successfully started
"""
self.alea.stop_recording()
self.recording = False
def set_detection_type(self, eventdetection):
"""Set the event detection type to either PyGaze algorithms, or
native algorithms as provided by the manufacturer (only if
available: detection type will default to PyGaze if no native
functions are available)
arguments
eventdetection -- a string indicating which detection type
should be employed: either 'pygaze' for
PyGaze event detection algorithms or
'native' for manufacturers algorithms (only
if available; will default to 'pygaze' if no
native event detection is available)
returns -- detection type for saccades, fixations and
blinks in a tuple, e.g.
('pygaze','native','native') when 'native'
was passed, but native detection was not
available for saccade detection
"""
if eventdetection in ['pygaze', 'native']:
self.eventdetection = eventdetection
return ('pygaze', 'pygaze', 'pygaze')
def wait_for_event(self, event):
"""Waits for event
arguments
event -- an integer event code, one of the following:
3 = STARTBLINK
4 = ENDBLINK
5 = STARTSACC
6 = ENDSACC
7 = STARTFIX
8 = ENDFIX
returns
outcome -- a self.wait_for_* method is called, depending on the
specified event; the return values of corresponding
method are returned
"""
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
"Error in libalea.AleaTracker.wait_for_event: eventcode {} is not supported"
.format(event))
return outcome
def wait_for_blink_end(self):
"""Waits for a blink end and returns the blink ending time
arguments
None
returns
timestamp -- blink ending time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# Native method
if self.eventdetection == 'native':
print("WARNING! 'native' event detection not implemented")
# # # # #
# PyGaze method
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def wait_for_blink_start(self):
"""Waits for a blink start and returns the blink starting time
arguments
None
returns
timestamp -- blink starting time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# Native method
if self.eventdetection == 'native':
print("WARNING! 'native' event detection not implemented")
# # # # #
# PyGaze method
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed BLINKTHRESH
if clock.get_time() - t0 >= self.blinkthresh:
# return timestamp of blink start
return t0
def wait_for_fixation_end(self):
"""Returns time and gaze position when a fixation has ended;
function assumes that a 'fixation' has ended when a deviation of
more than self.pxfixtresh from the initial fixation position has
been detected (self.pxfixtresh is created in self.calibration,
based on self.fixtresh, a property defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# Native method
if self.eventdetection == 'native':
print("WARNING! 'native' event detection not implemented")
# # # # #
# PyGaze method
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0] - spos[0])**2 + (
npos[1] -
spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_fixation_start(self):
"""Returns starting time and position when a fixation is started;
function assumes a 'fixation' has started when gaze position
remains reasonably stable (i.e. when most deviant samples are
within self.pxfixtresh) for five samples in a row (self.pxfixtresh
is created in self.calibration, based on self.fixtresh, a property
defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# Native method
if self.eventdetection == 'native':
print("WARNING! 'native' event detection not implemented")
# # # # #
# PyGaze method
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0] - spos[0])**2 + (
npos[1] -
spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a saccade is
ended; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos, endpos -- endtime in milliseconds (from
expbegintime); startpos and endpos
are (x,y) gaze position tuples
"""
# # # # #
# Native method
if self.eventdetection == 'native':
print("WARNING! 'native' event detection not implemented")
# # # # #
# PyGaze method
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0] - spos[0])**2 + (prevpos[1] - spos[1])**
2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1 - t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0] - prevpos[0])**2 + (newpos[1] - prevpos[1])**
2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (
t1 - t0
) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1 * self.pxacctresh
and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a saccade is
started; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos -- endtime in milliseconds (from expbegintime);
startpos is an (x,y) gaze position tuple
"""
# # # # #
# Native method
if self.eventdetection == 'native':
print("WARNING! 'native' event detection not implemented")
# # # # #
# PyGaze method
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0] - prevpos[0]
sy = newpos[1] - prevpos[1]
if (sx / self.pxdsttresh[0])**2 + (
sy / self.pxdsttresh[1]
)**2 > self.weightdist: # weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**
2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def is_valid_sample(self, gazepos):
"""Checks if the sample provided is valid (for internal use)
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (None, None) or gazepos == (-1, -1) or gazepos == (0, 0):
return False
# in any other case, the sample is valid
return True
class EyelinkGraphics(custom_display):
"""
Implements the EyeLink graphics that are shown on the experimental PC, such
as the camera image, and the calibration dots. This class only implements
the drawing operations, and little to no of the logic behind the set-up,
which is implemented in PyLink.
"""
def __init__(self, libeyelink, tracker):
"""
Constructor.
Arguments:
libeyelink -- A libeyelink object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.libeyelink = libeyelink
self.display = libeyelink.display
self.screen = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=0)
self.mouse = Mouse(timeout=0)
if DISPTYPE == 'pygame':
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
#if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), '__eyelink__.jpg')
# drawing properties
self.xc = self.display.dispsize[0]/2
self.yc = self.display.dispsize[1]/2
self.extra_info = True
self.ld = 40 # line distance
self.fontsize = libeyelink.fontsize
self.title = ""
self.display_open = True
# menu
self.menuscreen = Screen(disptype=DISPTYPE, mousevisible=False)
self.menuscreen.draw_text(text="Eyelink calibration menu",
pos=(self.xc,self.yc-6*self.ld), center=True, font='mono',
fontsize=int(2*self.fontsize), antialias=True)
self.menuscreen.draw_text(text="%s (pygaze %s, pylink %s)" \
% (libeyelink.eyelink_model, pygaze.version, pylink.__version__),
pos=(self.xc,self.yc-5*self.ld), center=True,
font='mono', fontsize=int(.8*self.fontsize), antialias=True)
self.menuscreen.draw_text(text="Press C to calibrate",
pos=(self.xc, self.yc-3*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press V to validate",
pos=(self.xc, self.yc-2*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press A to auto-threshold",
pos=(self.xc,self.yc-1*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press I to toggle extra info in camera image",
pos=(self.xc,self.yc-0*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press Enter to show camera image",
pos=(self.xc,self.yc+1*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(
text="(then change between images using the arrow keys)",
pos=(self.xc, self.yc+2*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press Escape to abort experiment",
pos=(self.xc, self.yc+4*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press Q to exit menu",
pos=(self.xc, self.yc+5*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
# beeps
self.__target_beep__ = Sound(osc='sine', freq=440, length=50,
attack=0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc='sine', freq=880, length=200,
attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc='sine', freq=220, length=200,
attack=0, decay=0, soundfile=None)
# Colors
self.color = {
pylink.CR_HAIR_COLOR: pygame.Color('white'),
pylink.PUPIL_HAIR_COLOR: pygame.Color('white'),
pylink.PUPIL_BOX_COLOR: pygame.Color('green'),
pylink.SEARCH_LIMIT_BOX_COLOR: pygame.Color('red'),
pylink.MOUSE_CURSOR_COLOR: pygame.Color('red'),
'font': pygame.Color('white'),
}
# Font
pygame.font.init()
self.font = pygame.font.SysFont('Courier New', 11)
# further properties
self.state = None
self.pal = None
self.size = (0,0)
self.set_tracker(tracker)
self.last_mouse_state = -1
self.bit64 = '64bit' in platform.architecture()
self.imagebuffer = self.new_array()
def close(self):
"""
Is called when the connection and display are shutting down.
"""
self.display_open = False
def new_array(self):
"""
Creates a new array with a system-specific format.
Returns:
An array.
"""
# On 64 bit Linux, we need to use an unsigned int data format.
# <https://www.sr-support.com/showthread.php?3215-Visual-glitch-when-/
# sending-eye-image-to-display-PC&highlight=ubuntu+pylink>
if os.name == 'posix' and self.bit64:
return array.array('I')
return array.array('L')
def set_tracker(self, tracker):
"""
Connects the tracker to the graphics environment.
Arguments:
tracker -- An tracker object as returned by pylink.EyeLink().
"""
self.tracker = tracker
self.tracker_version = tracker.getTrackerVersion()
if self.tracker_version >= 3:
self.tracker.sendCommand("enable_search_limits=YES")
self.tracker.sendCommand("track_search_limits=YES")
self.tracker.sendCommand("autothreshold_click=YES")
self.tracker.sendCommand("autothreshold_repeat=YES")
self.tracker.sendCommand("enable_camera_position_detect=YES")
def setup_cal_display(self):
"""
Sets up the initial calibration display, which contains a menu with
instructions.
"""
# show instructions
self.display.fill(self.menuscreen)
self.display.show()
def exit_cal_display(self):
"""Exits calibration display."""
self.clear_cal_display()
def record_abort_hide(self):
"""TODO: What does this do?"""
pass
def clear_cal_display(self):
"""Clears the calibration display"""
self.display.fill()
self.display.show()
def erase_cal_target(self):
"""TODO: What does this do?"""
self.clear_cal_display()
def draw_cal_target(self, x, y):
"""
Draws calibration target.
Arguments:
x -- The X coordinate of the target.
y -- The Y coordinate of the target.
"""
self.play_beep(pylink.CAL_TARG_BEEP)
self.screen.clear()
self.screen.draw_fixation(fixtype='dot', pos=(x,y))
self.display.fill(screen=self.screen)
self.display.show()
def play_beep(self, beepid):
"""
Plays a sound.
Arguments:
beepid -- A number that identifies the sound.
"""
if beepid == pylink.CAL_TARG_BEEP:
# For some reason, playing the beep here doesn't work, so we have
# to play it when the calibration target is drawn.
if EYELINKCALBEEP:
self.__target_beep__.play()
elif beepid == pylink.CAL_ERR_BEEP or beepid == pylink.DC_ERR_BEEP:
# show a picture
self.screen.clear()
self.screen.draw_text(
text="calibration lost, press 'Enter' to return to menu",
pos=(self.xc,self.yc), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.display.fill(self.screen)
self.display.show()
# play beep
self.__target_beep__error__.play()
elif beepid == pylink.CAL_GOOD_BEEP:
self.screen.clear()
if self.state == "calibration":
self.screen.draw_text(
text="Calibration succesfull, press 'v' to validate",
pos=(self.xc,self.yc), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
elif self.state == "validation":
self.screen.draw_text(
text="Validation succesfull, press 'Enter' to return to menu",
pos=(self.xc,self.yc), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
else:
self.screen.draw_text(text="Press 'Enter' to return to menu",
pos=(self.xc,self.yc), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
# show screen
self.display.fill(self.screen)
self.display.show()
# play beep
self.__target_beep__done__.play()
else: # DC_GOOD_BEEP or DC_TARG_BEEP
pass
def draw_line(self, x1, y1, x2, y2, colorindex):
"""
Unlike the function name suggests, this draws a single pixel. I.e.
the end coordinates are always exactly one pixel away from the start
coordinates.
Arguments:
x1 -- The starting x.
y1 -- The starting y.
x2 -- The end x.
y2 -- The end y.
colorIndex -- A color index.
"""
x1 = int(self.scale*x1)
y1 = int(self.scale*y1)
x2 = int(self.scale*x2)
y2 = int(self.scale*y2)
pygame.draw.line(self.cam_img, self.color[colorindex], (x1, y1),
(x2, y2))
def draw_lozenge(self, x, y, w, h, colorindex):
"""
desc:
Draws a rectangle.
arguments:
x:
desc: X coordinate.
type: int
y:
desc: Y coordinate.
type: int
w:
desc: A width.
type: int
h:
desc: A height.
type: int
colorindex:
desc: A colorindex.
type: int
"""
x = int(self.scale*x)
y = int(self.scale*y)
w = int(self.scale*w)
h = int(self.scale*h)
pygame.draw.rect(self.cam_img, self.color[colorindex], (x, y, w, h), 2)
def draw_title(self):
"""
desc:
Draws title info.
"""
y = 0
for line in self.title:
surf = self.font.render(line, 0, self.color['font'])
self.cam_img.blit(surf, (1, y))
y += 12
def get_mouse_state(self):
"""
desc:
Gets the mouse position and state.
returns:
desc: A (pos, state) tuple.
type: tuple.
"""
button, pos, time = self.mouse.get_clicked()
if button == None:
button = -1
if pos == None:
pos = self.mouse.get_pos()
return pos, button
def get_input_key(self):
"""
Gets an input key.
Returns:
A list containing a single pylink key identifier.
"""
# Don't try to collect key presses when the display is no longer
# available. This is necessary, because pylink polls key presses during
# file transfer, which generally occurs after the display has been
# closed.
if not self.display_open:
return None
try:
key, time = self.kb.get_key(keylist=None, timeout='default')
except:
self.esc_pressed = True
key = 'q'
if key == None:
return None
# Escape functions as a 'q' with the additional esc_pressed flag
if key == 'escape':
key = 'q'
self.esc_pressed = True
# Process regular keys
if key == "return":
keycode = pylink.ENTER_KEY
self.state = None
elif key == "space":
keycode = ord(" ")
elif key == "q":
keycode = pylink.ESC_KEY
self.state = None
elif key == "c":
keycode = ord("c")
self.state = "calibration"
elif key == "v":
keycode = ord("v")
self.state = "validation"
elif key == "a":
keycode = ord("a")
elif key == "i":
self.extra_info = not self.extra_info
keycode = 0
elif key == "up":
keycode = pylink.CURS_UP
elif key == "down":
keycode = pylink.CURS_DOWN
elif key == "left":
keycode = pylink.CURS_LEFT
elif key == "right":
keycode = pylink.CURS_RIGHT
else:
keycode = 0
# Convert key to PyLink keycode and return
return [pylink.KeyInput(keycode, 0)] # 0 = pygame.KMOD_NONE
def exit_image_display(self):
"""Exits the image display."""
self.clear_cal_display()
def alert_printf(self,msg):
"""
Prints alert message.
Arguments:
msg -- The message to be played.
"""
print "eyelink_graphics.alert_printf(): %s" % msg
def setup_image_display(self, width, height):
"""
Initializes the buffer that will contain the camera image.
Arguments:
width -- The width of the image.
height -- The height of the image.
"""
self.size = width, height
self.clear_cal_display()
self.last_mouse_state = -1
self.imagebuffer = self.new_array()
def image_title(self, text):
"""
Sets the current image title.
Arguments:
text -- An image title.
"""
while ': ' in text:
text = text.replace(': ', ':')
self.title = text.split()
def draw_image_line(self, width, line, totlines, buff):
"""
Draws a single eye video frame, line by line.
Arguments:
width -- Width of the video.
line -- Line nr of current line.
totlines -- Total lines in video.
buff -- Frame buffer.
imagesize -- The size of the image, which is (usually?) 192x160 px.
"""
# If the buffer hasn't been filled yet, add a line.
for i in range(width):
try:
self.imagebuffer.append(self.pal[buff[i]])
except:
pass
# If the buffer is full, push it to the display.
if line == totlines:
self.scale = totlines/320.
self._size = int(self.scale*self.size[0]), int(
self.scale*self.size[1])
# Convert the image buffer to a pygame image, save it ...
self.cam_img = pygame.image.fromstring(self.imagebuffer.tostring(),
self._size, 'RGBX')
if self.extra_info:
self.draw_cross_hair()
self.draw_title()
pygame.image.save(self.cam_img, self.tmp_file)
# ... and then show the image.
self.screen.clear()
self.screen.draw_image(self.tmp_file, scale=1.5/self.scale)
self.display.fill(self.screen)
self.display.show()
# Clear the buffer for the next round!
self.imagebuffer = self.new_array()
def set_image_palette(self, r, g, b):
"""
Sets the image palette.
TODO: What this function actually does is highly mysterious. Figure it
out!
Arguments:
r -- The red channel.
g -- The green channel.
b -- The blue channel.
"""
self.imagebuffer = self.new_array()
self.clear_cal_display()
sz = len(r)
i = 0
self.pal = []
while i < sz:
rf = int(b[i])
gf = int(g[i])
bf = int(r[i])
self.pal.append((rf<<16) | (gf<<8) | (bf))
i += 1
# PyGaze from constants import * from pygaze.display import Display from pygaze.screen import Screen from pygaze.eyetracker import EyeTracker from pygaze.keyboard import Keyboard from pygaze.libtime import clock # # # # # # SETUP # visuals disp = Display() scr = Screen() # input tracker = EyeTracker(disp) kb = Keyboard(keylist=None, timeout=None) # calibrate tracker.calibrate() # starting screen scr.clear() scr.draw_text(text="Press Space to start") disp.fill(scr) disp.show() kb.get_key(keylist=['space'], timeout=None, flush=True)
class EyeTribeTracker(BaseEyeTracker):
"""A class for EyeTribeTracker objects"""
def __init__(self,
display,
logfile=settings.LOGFILE,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
blink_threshold=settings.BLINKTHRESH,
**args):
"""Initializes the EyeTribeTracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
logfile -- logfile name (string value); note that this is the
name for the eye data log file (default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, EyeTribeTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = settings.DISPSIZE # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# output file properties
self.outputfile = logfile
# eye tracker properties
self.connected = False
self.recording = False
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = 30 # initial error in pixels
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# connect to the tracker
self.eyetribe = EyeTribe(logfilename=logfile)
# get info on the sample rate
self.samplerate = self.eyetribe._samplefreq
self.sampletime = 1000.0 * self.eyetribe._intsampletime
# initiation report
self.log("pygaze initiation report start")
self.log("display resolution: {}x{}".format(self.dispsize[0],
self.dispsize[1]))
self.log("display size in cm: {}x{}".format(self.screensize[0],
self.screensize[1]))
self.log("samplerate: {} Hz".format(self.samplerate))
self.log("sampletime: {} ms".format(self.sampletime))
self.log("fixation threshold: {} degrees".format(self.fixtresh))
self.log("speed threshold: {} degrees/second".format(self.spdtresh))
self.log("acceleration threshold: {} degrees/second**2".format(
self.accthresh))
self.log("pygaze initiation report end")
def calibrate(self):
"""Calibrates the eye tracking system
arguments
None
keyword arguments
None
returns
success -- returns True if calibration succeeded, or False if
not; in addition a calibration log is added to the
log file and some properties are updated (i.e. the
thresholds for detection algorithms)
"""
# CALIBRATION
# determine the calibration points
calibpoints = []
for x in [0.1, 0.5, 0.9]:
for y in [0.1, 0.5, 0.9]:
calibpoints.append(
(int(x * self.dispsize[0]), int(y * self.dispsize[1])))
random.shuffle(calibpoints)
# show a message
self.screen.clear()
self.screen.draw_text(
text="Press Space to calibrate, S to skip, and Q to quit",
fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# wait for keyboard input
key, keytime = self.kb.get_key(keylist=['q', 's', 'space'],
timeout=None,
flush=True)
if key == 's':
return True
if key == 'q':
quited = True
else:
quited = False
# Pause the processing of samples during the calibration.
# self.eyetribe._pause_sample_processing()
# run until the user is statisfied, or quits
calibrated = False
calibresult = None
while not quited and not calibrated:
# Clear the existing calibration.
if self.eyetribe._tracker.get_iscalibrated():
self.eyetribe._lock.acquire(True)
self.eyetribe.calibration.clear()
self.eyetribe._lock.release()
# Wait for a bit.
clock.pause(1500)
# start a new calibration
if not self.eyetribe._tracker.get_iscalibrating():
self.eyetribe._lock.acquire(True)
self.eyetribe.calibration.start(pointcount=len(calibpoints))
self.eyetribe._lock.release()
# loop through calibration points
for cpos in calibpoints:
# Check whether the calibration is already done.
# (Not sure how or why, but for some reason some data
# can persist between calbrations, and the tracker will
# simply stop allowing further pointstart requests.)
if self.eyetribe._tracker.get_iscalibrated():
break
# Draw a calibration target.
self.draw_calibration_target(cpos[0], cpos[1])
# wait for a bit to allow participant to start looking at
# the calibration point (#TODO: space press?)
clock.pause(settings.EYETRIBEPRECALIBDUR)
# start calibration of point
self.eyetribe._lock.acquire(True)
self.eyetribe.calibration.pointstart(cpos[0], cpos[1])
self.eyetribe._lock.release()
# wait for a second
clock.pause(settings.EYETRIBECALIBDUR)
# stop calibration of this point
self.eyetribe._lock.acquire(True)
self.eyetribe.calibration.pointend()
self.eyetribe._lock.release()
# check if the Q key has been pressed
if self.kb.get_key(keylist=['q'], timeout=10,
flush=False)[0] == 'q':
# abort calibration
self.eyetribe._lock.acquire(True)
self.eyetribe.calibration.abort()
self.eyetribe._lock.release()
# set quited variable and break this for loop
quited = True
break
# retry option if the calibration was aborted
if quited:
# show retry message
self.screen.clear()
self.screen.draw_text(
"Calibration aborted. Press Space to restart or 'Q' to quit",
fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# get input
key, keytime = self.kb.get_key(keylist=['q', 'space'],
timeout=None,
flush=True)
if key == 'space':
# unset quited Boolean
quited = False
# skip further processing
continue
# empty display
self.disp.fill()
self.disp.show()
# allow for a bit of calculation time
# (this is waaaaaay too much)
clock.pause(1000)
# get the calibration result
self.eyetribe._lock.acquire(True)
calibresult = self.eyetribe._tracker.get_calibresult()
self.eyetribe._lock.release()
# results
# clear the screen
self.screen.clear()
# draw results for each point
if type(calibresult) == dict:
for p in calibresult['calibpoints']:
# only draw the point if data was obtained
if p['state'] > 0:
# draw the mean error
# self.screen.draw_circle(colour=(252,233,79),
# pos=(p['cpx'],p['cpy']), r=p['mepix'], pw=0,
# fill=True)
self.screen.draw_line(spos=(p['cpx'], p['cpy']),
epos=(p['mecpx'], p['mecpy']),
pw=2)
# draw the point
self.screen.draw_fixation(fixtype='dot',
colour=(115, 210, 22),
pos=(p['cpx'], p['cpy']))
# draw the estimated point
self.screen.draw_fixation(fixtype='dot',
colour=(32, 74, 135),
pos=(p['mecpx'], p['mecpy']))
# annotate accuracy
self.screen.draw_text(text="{}".format(\
round(p['acd'], ndigits=2)),
pos=(p['cpx']+10,p['cpy']+10), fontsize=20)
# if no data was obtained, draw the point in red
else:
self.screen.draw_fixation(fixtype='dot',
colour=(204, 0, 0),
pos=(p['cpx'], p['cpy']))
# draw box for averages
# self.screen.draw_rect(colour=(238,238,236), x=int(self.dispsize[0]*0.15), y=int(self.dispsize[1]*0.2), w=400, h=200, pw=0, fill=True)
# draw result
if calibresult['result']:
self.screen.draw_text(text="Calibration successful",
colour=(0, 255, 0),
pos=(int(self.dispsize[0] * 0.5),
int(self.dispsize[1] * 0.25)),
fontsize=20)
else:
self.screen.draw_text(text="Calibration failed",
colour=(255, 0, 0),
pos=(int(self.dispsize[0] * 0.5),
int(self.dispsize[1] * 0.25)),
fontsize=20)
# draw average accuracy
self.screen.draw_text(
text="Average error = {} degrees".format(round(\
calibresult['deg'], ndigits=2)), \
pos=(int(self.dispsize[0]*0.5),int(self.dispsize[1]*0.25+30)),
fontsize=20)
# draw input options
self.screen.draw_text(
text="Press Space to continue or 'R' to restart",
pos=(int(self.dispsize[0] * 0.5),
int(self.dispsize[1] * 0.25 + 60)),
fontsize=20)
else:
self.screen.draw_text(
text="Calibration failed. Press 'R' to try again.",
fontsize=20)
# show the results
self.disp.fill(self.screen)
self.disp.show()
# wait for input
key, keytime = self.kb.get_key(keylist=['space', 'r'],
timeout=None,
flush=True)
# process input
if key == 'space':
calibrated = True
# Continue the processing of samples after the calibration.
# self.eyetribe._unpause_sample_processing()
# calibration failed if the user quited
if quited:
return False
# NOISE CALIBRATION
# get all error estimates (pixels)
var = []
for p in calibresult['calibpoints']:
# only draw the point if data was obtained
if p['state'] > 0:
var.append(p['mepix'])
noise = sum(var) / float(len(var))
self.pxdsttresh = (noise, noise)
# AFTERMATH
# store some variables
pixpercm = (self.dispsize[0] / float(self.screensize[0]) +
self.dispsize[1] / float(self.screensize[1])) / 2
screendist = settings.SCREENDIST
# calculate thresholds based on tracker settings
self.accuracy = ((calibresult['Ldeg'], calibresult['Ldeg']),
(calibresult['Rdeg'], calibresult['Rdeg']))
self.pxerrdist = deg2pix(screendist, self.errdist, pixpercm)
self.pxfixtresh = deg2pix(screendist, self.fixtresh, pixpercm)
self.pxaccuracy = ((deg2pix(screendist, self.accuracy[0][0], pixpercm),
deg2pix(screendist, self.accuracy[0][1],
pixpercm)),
(deg2pix(screendist, self.accuracy[1][0], pixpercm),
deg2pix(screendist, self.accuracy[1][1],
pixpercm)))
self.pxspdtresh = deg2pix(screendist, self.spdtresh / 1000.0,
pixpercm) # in pixels per millisecond
self.pxacctresh = deg2pix(screendist, self.accthresh / 1000.0,
pixpercm) # in pixels per millisecond**2
# calibration report
self.log("pygaze calibration report start")
self.log("accuracy (degrees): LX={}, LY={}, RX={}, RY={}".format(
self.accuracy[0][0], self.accuracy[0][1], self.accuracy[1][0], \
self.accuracy[1][1]))
self.log("accuracy (in pixels): LX={}, LY={}, RX={}, RY={}".format( \
self.pxaccuracy[0][0], self.pxaccuracy[0][1], \
self.pxaccuracy[1][0], self.pxaccuracy[1][1]))
self.log("precision (RMS noise in pixels): X={}, Y={}".format( \
self.pxdsttresh[0], self.pxdsttresh[1]))
self.log("distance between participant and display: {} cm".format( \
screendist))
self.log("fixation threshold: {} pixels".format(self.pxfixtresh))
self.log("speed threshold: {} pixels/ms".format(self.pxspdtresh))
self.log("acceleration threshold: {} pixels/ms**2".format( \
self.pxacctresh))
self.log("pygaze calibration report end")
return True
def close(self):
"""Neatly close connection to tracker
arguments
None
returns
Nothing -- saves data and sets self.connected to False
"""
# close connection
self.eyetribe.close()
self.connected = False
def connected(self):
"""Checks if the tracker is connected
arguments
None
returns
connected -- True if connection is established, False if not;
sets self.connected to the same value
"""
res = self.eyetribe._tracker.get_trackerstate()
if res == 0:
self.connected = True
else:
self.connected = False
return self.connected
def drift_correction(self, pos=None, fix_triggered=False):
"""Performs a drift check
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
fix_triggered -- Boolean indicating if drift check should be
performed based on gaze position (fix_triggered
= True) or on spacepress (fix_triggered =
False) (default = False)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
self.draw_drift_correction_target(pos[0], pos[1])
pressed = False
while not pressed:
pressed, presstime = self.kb.get_key()
if pressed:
if pressed == 'escape' or pressed == 'q':
print(
"libeyetribe.EyeTribeTracker.drift_correction: 'q' or 'escape' pressed"
)
return self.calibrate()
gazepos = self.sample()
if ((gazepos[0] - pos[0])**2 +
(gazepos[1] - pos[1])**2)**0.5 < self.pxerrdist:
return True
else:
self.errorbeep.play()
return False
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.screen.clear()
self.screen.draw_fixation(fixtype='dot',
colour=settings.FGC,
pos=(x, y),
pw=0,
diameter=12)
self.disp.fill(self.screen)
self.disp.show()
def draw_calibration_target(self, x, y):
self.draw_drift_correction_target(x, y)
def fix_triggered_drift_correction(self,
pos=None,
min_samples=10,
max_dev=60,
reset_threshold=30):
"""Performs a fixation triggered drift correction by collecting
a number of samples and calculating the average distance from the
fixation position
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
min_samples -- minimal amount of samples after which an
average deviation is calculated (default = 10)
max_dev -- maximal deviation from fixation in pixels
(default = 60)
reset_threshold -- if the horizontal or vertical distance in
pixels between two consecutive samples is
larger than this threshold, the sample
collection is reset (default = 30)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
self.draw_drift_correction_target(pos[0], pos[1])
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key()[0] in ['escape', 'q']:
print(
"libeyetribe.EyeTribeTracker.fix_triggered_drift_correction: 'q' or 'escape' pressed"
)
return self.calibrate()
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold
or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0])**2 + (avg_y - pos[1])**2)**0.5
if d < max_dev:
return True
else:
lx = []
ly = []
def get_eyetracker_clock_async(self):
"""Not supported for EyeTribeTracker (yet)"""
print("function not supported yet")
def log(self, msg):
"""Writes a message to the log file
arguments
ms -- a string to include in the log file
returns
Nothing -- uses native log function of iViewX to include a line
in the log file
"""
self.eyetribe.log_message(msg)
def prepare_drift_correction(self, pos):
"""Not supported for EyeTribeTracker (yet)"""
print("function not supported yet")
def pupil_size(self):
"""Return pupil size
arguments
None
returns
pupil size -- returns pupil diameter for the eye that is currently
being tracked (as specified by self.eye_used) or -1
when no data is obtainable
"""
# get newest pupil size
ps = self.eyetribe.pupil_size()
# invalid data
if ps == None:
return -1
# check if the new pupil size is the same as the previous
if ps != self.prevps:
# update the pupil size
self.prevps = copy.copy(ps)
return self.prevps
def sample(self):
"""Returns newest available gaze position
arguments
None
returns
sample -- an (x,y) tuple or a (-1,-1) on an error
"""
# get newest sample
s = self.eyetribe.sample()
# invalid data
if s == (None, None):
return (-1, -1)
# check if the new sample is the same as the previous
if s != self.prevsample:
# update the current sample
self.prevsample = copy.copy(s)
return self.prevsample
def send_command(self, cmd):
"""Sends a command to the eye tracker
arguments
cmd -- the command to be sent to the EyeTribe, which should
be a list with the following information:
[category, request, values]
returns
Nothing
"""
self.eyetribe._connection.request(cmd)
def start_recording(self):
"""Starts recording eye position
arguments
None
returns
Nothing -- sets self.recording to True when recording is
successfully started
"""
self.eyetribe.start_recording()
self.recording = True
def status_msg(self, msg):
"""Not supported for EyeTribeTracker (yet)"""
print("function not supported yet")
def stop_recording(self):
"""Stop recording eye position
arguments
None
returns
Nothing -- sets self.recording to False when recording is
successfully started
"""
self.eyetribe.stop_recording()
self.recording = False
def set_detection_type(self, eventdetection):
"""Set the event detection type to either PyGaze algorithms, or
native algorithms as provided by the manufacturer (only if
available: detection type will default to PyGaze if no native
functions are available)
arguments
eventdetection -- a string indicating which detection type
should be employed: either 'pygaze' for
PyGaze event detection algorithms or
'native' for manufacturers algorithms (only
if available; will default to 'pygaze' if no
native event detection is available)
returns -- detection type for saccades, fixations and
blinks in a tuple, e.g.
('pygaze','native','native') when 'native'
was passed, but native detection was not
available for saccade detection
"""
if eventdetection in ['pygaze', 'native']:
self.eventdetection = eventdetection
return ('pygaze', 'pygaze', 'pygaze')
def wait_for_event(self, event):
"""Waits for event
arguments
event -- an integer event code, one of the following:
3 = STARTBLINK
4 = ENDBLINK
5 = STARTSACC
6 = ENDSACC
7 = STARTFIX
8 = ENDFIX
returns
outcome -- a self.wait_for_* method is called, depending on the
specified event; the return values of corresponding
method are returned
"""
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
"Error in libeyetribe.EyeTribeTracker.wait_for_event: eventcode {} is not supported"
.format(event))
return outcome
def wait_for_blink_end(self):
"""Waits for a blink end and returns the blink ending time
arguments
None
returns
timestamp -- blink ending time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def wait_for_blink_start(self):
"""Waits for a blink start and returns the blink starting time
arguments
None
returns
timestamp -- blink starting time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed BLINKTHRESH
if clock.get_time() - t0 >= self.blinkthresh:
# return timestamp of blink start
return t0
def wait_for_fixation_end(self):
"""Returns time and gaze position when a fixation has ended;
function assumes that a 'fixation' has ended when a deviation of
more than self.pxfixtresh from the initial fixation position has
been detected (self.pxfixtresh is created in self.calibration,
based on self.fixtresh, a property defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer fixation detection; \
PyGaze algorithm will be used")
# # # # #
# PyGaze method
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0] - spos[0])**2 + (
npos[1] -
spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_fixation_start(self):
"""Returns starting time and position when a fixation is started;
function assumes a 'fixation' has started when gaze position
remains reasonably stable (i.e. when most deviant samples are
within self.pxfixtresh) for five samples in a row (self.pxfixtresh
is created in self.calibration, based on self.fixtresh, a property
defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a fixation start
# detection built into their API (only ending)
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer fixation detection; \
PyGaze algorithm will be used")
# # # # #
# PyGaze method
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0] - spos[0])**2 + (
npos[1] -
spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a saccade is
ended; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos, endpos -- endtime in milliseconds (from
expbegintime); startpos and endpos
are (x,y) gaze position tuples
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0] - spos[0])**2 + (prevpos[1] - spos[1])**
2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1 - t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0] - prevpos[0])**2 + (newpos[1] - prevpos[1])**
2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (
t1 - t0
) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1 * self.pxacctresh
and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a saccade is
started; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos -- endtime in milliseconds (from expbegintime);
startpos is an (x,y) gaze position tuple
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0] - prevpos[0]
sy = newpos[1] - prevpos[1]
if (sx / self.pxdsttresh[0])**2 + (
sy / self.pxdsttresh[1]
)**2 > self.weightdist: # weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**
2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1 - t0)
# calculate acceleration
a = (v1 - v0) / (t1 - t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def is_valid_sample(self, gazepos):
"""Checks if the sample provided is valid, based on EyeTribe specific
criteria (for internal use)
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (None, None) or gazepos == (-1, -1):
return False
# in any other case, the sample is valid
return True
# # # # #
# directory stuff
DIR = os.path.split(os.path.abspath(__file__))[0]
soundfile = os.path.join(DIR, 'bark.ogg')
imagefile = os.path.join(DIR, 'kitten.png')
# # # # #
# create instances
# initialize the display
disp = Display()
# initialize a screen
scr = Screen()
# initialize a keyboard
kb = Keyboard(keylist=['space'],timeout=None)
# initialize a mouse
mouse = Mouse(mousebuttonlist=None, timeout=None)
# initialize a sound
snd = Sound(osc='sine', freq=4400, length=3000)
sounds = {
'a sine wave (slightly oscillating)':Sound(osc='sine', freq=440, length=5000, attack=1000, decay=1000),
'a saw wave':Sound(osc='saw', freq=880, length=5000, attack=0, decay=0),
'a square wave':Sound(osc='square', freq=1760, length=5000, attack=0, decay=0),
'white noise':Sound(osc='whitenoise'),
'soundfile':Sound(soundfile=soundfile)
# # # # # # directory stuff DIR = os.path.split(os.path.abspath(__file__))[0] soundfile = os.path.join(DIR, 'bark.ogg') imagefile = os.path.join(DIR, 'kitten.png') # # # # # # create instances # initialize the display disp = Display() # initialize a screen scr = Screen() # initialize an EyeTracker tracker = EyeTracker(disp) # initialize a keyboard kb = Keyboard(keylist=['space'],timeout=None) # initialize a sound snd = Sound(soundfile=soundfile) # initialize a Timer timer = Time() # create a new logfile log = Logfile(filename="test")
def __init__(self, display,
logfile=settings.LOGFILE, \
eventdetection=settings.EVENTDETECTION, \
saccade_velocity_threshold=35, \
saccade_acceleration_threshold=9500, \
blink_threshold=settings.BLINKTHRESH, \
**args):
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, EyeLogicTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
self.disp = display
self.screen = Screen()
self.dispsize = self.disp.dispsize # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# show a message
self.screen.clear()
self.screen.draw_text(
text="Initialising the eye tracker, please wait...",
fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# output file properties
self.logfile = logfile
# eye tracker properties
self._recording = Event()
self._recording.clear()
self._calibrated = Event()
self._calibrated.clear()
self.eye_used = 2 # 0=left, 1=right, 2=binocular
self.sampleLock = Lock()
self.lastSample = None
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
# event detection properties
self.pxfixtresh = 50;
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self._log_vars = [ \
"timestampMicroSec", \
"index", \
"porFilteredX", \
"porFilteredY", \
"porLeftX", \
"porLeftY", \
"pupilRadiusLeft", \
"porRightX", \
"porRightY", \
"pupilRadiusRight", \
]
# Open a new log file.
dir_name = os.path.dirname(logfile)
file_name = os.path.basename(logfile)
name, ext = os.path.splitext(file_name)
self._data_file_path = os.path.join(dir_name, name+".eyelogic.csv")
self._log_file = open(self._data_file_path, "w")
# Write a header to the log.
header = ["TYPE"]
header.extend(self._log_vars)
self._sep = ";"
self._log_file.write("Sep="+self._sep+"\n")
self._log_file.write(self._sep.join(map(str, header)))
# Create a lock to prevent simultaneous access to the log file.
self._logging_queue = Queue()
self._logging_queue_empty = Event()
self._logging_queue_empty.set()
self._connected = Event()
self._connected.set()
self._log_counter = 0
self._log_consolidation_freq = 60
self._logging_thread = Thread( target=self.loggingThread, \
name='PyGaze_EyeLogic_Logging', args=[])
global g_api
g_api = self
# log
self.log("pygaze initiation")
#self.log("experiment = {}".format(self.description))
#self.log("participant = {}".format(self.participant))
self.log("display resolution = {}x{}".format(self.dispsize[0], \
self.dispsize[1]))
self.log("display size in cm = {}x{}".format(self.screensize[0], \
self.screensize[1]))
self.log("fixation threshold = {} degrees".format(self.fixtresh))
self.log("speed threshold = {} degrees/second".format(self.spdtresh))
self.log("acceleration threshold = {} degrees/second**2".format( \
self.accthresh))
# connect
self.api = ELApi( "PyGaze" )
self.api.registerGazeSampleCallback( gazeSampleCallback )
self.api.registerEventCallback( eventCallback )
resultConnect = self.api.connect()
if (resultConnect != ELApi.ReturnConnect.SUCCESS):
self._connected.clear()
raise Exception("Cannot connect to EyeLogic server = {}".format(errorstringConnect(resultConnect)))
self._connected.set()
screenConfig = self.api.getScreenConfig()
self.log("eye tracker is mounted on screen {}".format(screenConfig.id))
self.rawResolution = (screenConfig.resolutionX, screenConfig.resolutionY)
self.log("raw screen resolution = {}x{}".format(
self.rawResolution[0], self.rawResolution[1]))
self.log("end pygaze initiation")
deviceConfig = self.api.getDeviceConfig()
if (deviceConfig.deviceSerial == 0):
raise Exception("no eye tracking device connected")
if (len(deviceConfig.frameRates) == 0):
raise Exception("failed to read out device configuration")
g_api.sampleRate = deviceConfig.frameRates[0]
g_api.sampleTime = 1000.0 / g_api.sampleRate
g_api.log("samplerate = {} Hz".format(g_api.sampleRate))
g_api.log("sampletime = {} ms".format(g_api.sampleTime))
self._logging_thread.start()
self.screen.clear()
self.disp.fill(self.screen)
self.disp.show()
def __init__(self, libeyelink, tracker):
"""
Constructor.
Arguments:
libeyelink -- A libeyelink object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.libeyelink = libeyelink
self.display = libeyelink.display
self.screen = Screen(disptype=settings.DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=0)
self.mouse = Mouse(timeout=0)
if settings.DISPTYPE == "pygame":
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
# if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), "__eyelink__.jpg")
# drawing properties
self.xc = self.display.dispsize[0] / 2
self.yc = self.display.dispsize[1] / 2
self.extra_info = True
self.ld = 40 # line distance
self.fontsize = libeyelink.fontsize
self.title = ""
self.display_open = True
self.draw_menu_screen()
# beeps
self.__target_beep__ = Sound(osc="sine", freq=440, length=50, attack=0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc="sine", freq=880, length=200, attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc="sine", freq=220, length=200, attack=0, decay=0, soundfile=None)
# Colors
self.color = {
pylink.CR_HAIR_COLOR: pygame.Color("white"),
pylink.PUPIL_HAIR_COLOR: pygame.Color("white"),
pylink.PUPIL_BOX_COLOR: pygame.Color("green"),
pylink.SEARCH_LIMIT_BOX_COLOR: pygame.Color("red"),
pylink.MOUSE_CURSOR_COLOR: pygame.Color("red"),
"font": pygame.Color("white"),
}
# Font
pygame.font.init()
self.font = pygame.font.SysFont("Courier New", 11)
# further properties
self.state = None
self.pal = None
self.size = (0, 0)
self.set_tracker(tracker)
self.last_mouse_state = -1
self.bit64 = "64bit" in platform.architecture()
self.imagebuffer = self.new_array()
def __init__(self, libeyelink, tracker):
"""
Constructor.
Arguments:
libeyelink -- A libeyelink object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.libeyelink = libeyelink
self.display = libeyelink.display
self.screen = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=0)
self.mouse = Mouse(timeout=0)
if DISPTYPE == 'pygame':
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
#if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), '__eyelink__.jpg')
# drawing properties
self.xc = self.display.dispsize[0]/2
self.yc = self.display.dispsize[1]/2
self.extra_info = True
self.ld = 40 # line distance
self.fontsize = libeyelink.fontsize
self.title = ""
self.display_open = True
# menu
self.menuscreen = Screen(disptype=DISPTYPE, mousevisible=False)
self.menuscreen.draw_text(text="Eyelink calibration menu",
pos=(self.xc,self.yc-6*self.ld), center=True, font='mono',
fontsize=int(2*self.fontsize), antialias=True)
self.menuscreen.draw_text(text="%s (pygaze %s, pylink %s)" \
% (libeyelink.eyelink_model, pygaze.version, pylink.__version__),
pos=(self.xc,self.yc-5*self.ld), center=True,
font='mono', fontsize=int(.8*self.fontsize), antialias=True)
self.menuscreen.draw_text(text="Press C to calibrate",
pos=(self.xc, self.yc-3*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press V to validate",
pos=(self.xc, self.yc-2*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press A to auto-threshold",
pos=(self.xc,self.yc-1*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press I to toggle extra info in camera image",
pos=(self.xc,self.yc-0*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press Enter to show camera image",
pos=(self.xc,self.yc+1*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(
text="(then change between images using the arrow keys)",
pos=(self.xc, self.yc+2*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press Escape to abort experiment",
pos=(self.xc, self.yc+4*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
self.menuscreen.draw_text(text="Press Q to exit menu",
pos=(self.xc, self.yc+5*self.ld), center=True, font='mono',
fontsize=self.fontsize, antialias=True)
# beeps
self.__target_beep__ = Sound(osc='sine', freq=440, length=50,
attack=0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc='sine', freq=880, length=200,
attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc='sine', freq=220, length=200,
attack=0, decay=0, soundfile=None)
# Colors
self.color = {
pylink.CR_HAIR_COLOR: pygame.Color('white'),
pylink.PUPIL_HAIR_COLOR: pygame.Color('white'),
pylink.PUPIL_BOX_COLOR: pygame.Color('green'),
pylink.SEARCH_LIMIT_BOX_COLOR: pygame.Color('red'),
pylink.MOUSE_CURSOR_COLOR: pygame.Color('red'),
'font': pygame.Color('white'),
}
# Font
pygame.font.init()
self.font = pygame.font.SysFont('Courier New', 11)
# further properties
self.state = None
self.pal = None
self.size = (0,0)
self.set_tracker(tracker)
self.last_mouse_state = -1
self.bit64 = '64bit' in platform.architecture()
self.imagebuffer = self.new_array()
class EyeTribeTracker(BaseEyeTracker):
"""A class for EyeTribeTracker objects"""
def __init__(self, display, logfile=LOGFILE, eventdetection=EVENTDETECTION, \
saccade_velocity_threshold=35, saccade_acceleration_threshold=9500, \
**args):
"""Initializes the EyeTribeTracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
logfile -- logfile name (string value); note that this is the
name for the eye data log file (default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, EyeTribeTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = DISPSIZE # display size in pixels
self.screensize = SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw',freq=100, length=100)
# output file properties
self.outputfile = logfile
# eye tracker properties
self.connected = False
self.recording = False
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = 30 # initial error in pixels
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1,-1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# connect to the tracker
self.eyetribe = EyeTribe(logfilename=logfile)
# get info on the sample rate
self.samplerate = self.eyetribe._samplefreq
self.sampletime = 1000.0 * self.eyetribe._intsampletime
# initiation report
self.log("pygaze initiation report start")
self.log("display resolution: %sx%s" % (self.dispsize[0],self.dispsize[1]))
self.log("display size in cm: %sx%s" % (self.screensize[0],self.screensize[1]))
self.log("samplerate: %.2f Hz" % self.samplerate)
self.log("sampletime: %.2f ms" % self.sampletime)
self.log("fixation threshold: %s degrees" % self.fixtresh)
self.log("speed threshold: %s degrees/second" % self.spdtresh)
self.log("acceleration threshold: %s degrees/second**2" % self.accthresh)
self.log("pygaze initiation report end")
def calibrate(self):
"""Calibrates the eye tracking system
arguments
None
keyword arguments
None
returns
success -- returns True if calibration succeeded, or False if
not; in addition a calibration log is added to the
log file and some properties are updated (i.e. the
thresholds for detection algorithms)
"""
# CALIBRATION
# determine the calibration points
calibpoints = []
for x in [0.1,0.5,0.9]:
for y in [0.1,0.5,0.9]:
calibpoints.append((int(x*self.dispsize[0]),int(y*self.dispsize[1])))
random.shuffle(calibpoints)
# show a message
self.screen.clear()
self.screen.draw_text(text="Press Space to start the calibration or Q to quit.")
self.disp.fill(self.screen)
self.disp.show()
# wait for keyboard input
key, keytime = self.kb.get_key(keylist=['q','space'], timeout=None, flush=True)
if key == 'q':
quited = True
else:
quited = False
# run until the user is statisfied, or quits
calibrated = False
calibresult = None
while not quited and not calibrated:
# start a new calibration
self.eyetribe.calibration.start(pointcount=len(calibpoints))
# loop through calibration points
for cpos in calibpoints:
self.draw_calibration_target(cpos[0], cpos[1])
# wait for a bit to allow participant to start looking at
# the calibration point (#TODO: space press?)
clock.pause(1000)
# start calibration of point
self.eyetribe.calibration.pointstart(cpos[0],cpos[1])
# wait for a second
clock.pause(1000)
# stop calibration of this point
result = self.eyetribe.calibration.pointend()
# the final calibration point returns a dict (does it?)
if type(result) == dict:
calibresult = copy.deepcopy(result)
# check if the Q key has been pressed
if self.kb.get_key(keylist=['q'],timeout=10,flush=False)[0] == 'q':
# abort calibration
self.eyetribe.calibration.abort()
# set quited variable and break this for loop
quited = True
break
# retry option if the calibration was aborted
if quited:
# show retry message
self.screen.clear()
self.screen.draw_text("Calibration aborted. Press Space to restart, or 'Q' to quit.")
self.disp.fill(self.screen)
self.disp.show()
# get input
key, keytime = self.kb.get_key(keylist=['q','space'], timeout=None, flush=True)
if key == 'space':
# unset quited Boolean
quited = False
# skip further processing
continue
# get the calibration result if it was not obtained yet
if type(calibresult) != dict:
# empty display
self.disp.fill()
self.disp.show()
# allow for a bit of calculation time
clock.pause(2000)
# get the result
calibresult = self.eyetribe._tracker.get_calibresult()
# results
# clear the screen
self.screen.clear()
# draw results for each point
if type(calibresult) == dict:
for p in calibresult['calibpoints']:
# only draw the point if data was obtained
if p['state'] > 0:
# draw the mean error
self.screen.draw_circle(colour=(252,233,79), pos=(p['cpx'],p['cpy']), r=p['mepix'], pw=0, fill=True)
# draw the point
self.screen.draw_fixation(fixtype='dot', colour=(115,210,22), pos=(p['cpx'],p['cpy']))
# draw the estimated point
self.screen.draw_fixation(fixtype='dot', colour=(32,74,135), pos=(p['mecpx'],p['mecpy']))
# annotate accuracy
self.screen.draw_text(text=str(p['acd']), pos=(p['cpx']+10,p['cpy']+10), fontsize=12)
# if no data was obtained, draw the point in red
else:
self.screen.draw_fixation(fixtype='dot', colour=(204,0,0), pos=(p['cpx'],p['cpy']))
# draw box for averages
self.screen.draw_rect(colour=(238,238,236), x=int(self.dispsize[0]*0.15), y=int(self.dispsize[1]*0.2), w=400, h=200, pw=0, fill=True)
# draw result
if calibresult['result']:
self.screen.draw_text(text="calibration is successful", colour=(115,210,22), pos=(int(self.dispsize[0]*0.25),int(self.dispsize[1]*0.25)), fontsize=12)
else:
self.screen.draw_text(text="calibration failed", colour=(204,0,0), pos=(int(self.dispsize[0]*0.25),int(self.dispsize[1]*0.25)), fontsize=12)
# draw average accuracy
self.screen.draw_text(text="average error = %.2f degrees" % (calibresult['deg']), colour=(211,215,207), pos=(int(self.dispsize[0]*0.25),int(self.dispsize[1]*0.25+20)), fontsize=12)
# draw input options
self.screen.draw_text(text="Press Space to continue, or 'R' to restart.", colour=(211,215,207), pos=(int(self.dispsize[0]*0.25),int(self.dispsize[1]*0.25+40)), fontsize=12)
else:
self.screen.draw_text(text="Calibration failed, press 'R' to try again.")
# show the results
self.disp.fill(self.screen)
self.disp.show()
# wait for input
key, keytime = self.kb.get_key(keylist=['space','r'], timeout=None, flush=True)
# process input
if key == 'space':
calibrated = True
# calibration failed if the user quited
if quited:
return False
# NOISE CALIBRATION
# get all error estimates (pixels)
var = []
for p in calibresult['calibpoints']:
# only draw the point if data was obtained
if p['state'] > 0:
var.append(p['mepix'])
noise = sum(var) / float(len(var))
self.pxdsttresh = (noise, noise)
# AFTERMATH
# store some variables
pixpercm = (self.dispsize[0]/float(self.screensize[0]) + self.dispsize[1]/float(self.screensize[1])) / 2
screendist = SCREENDIST
# calculate thresholds based on tracker settings
self.accuracy = ((calibresult['Ldeg'],calibresult['Ldeg']), (calibresult['Rdeg'],calibresult['Rdeg']))
self.pxerrdist = deg2pix(screendist, self.errdist, pixpercm)
self.pxfixtresh = deg2pix(screendist, self.fixtresh, pixpercm)
self.pxaccuracy = ((deg2pix(screendist, self.accuracy[0][0], pixpercm),deg2pix(screendist, self.accuracy[0][1], pixpercm)), (deg2pix(screendist, self.accuracy[1][0], pixpercm),deg2pix(screendist, self.accuracy[1][1], pixpercm)))
self.pxspdtresh = deg2pix(screendist, self.spdtresh/1000.0, pixpercm) # in pixels per millisecond
self.pxacctresh = deg2pix(screendist, self.accthresh/1000.0, pixpercm) # in pixels per millisecond**2
# calibration report
self.log("pygaze calibration report start")
self.log("accuracy (degrees): LX=%s, LY=%s, RX=%s, RY=%s" % (self.accuracy[0][0],self.accuracy[0][1],self.accuracy[1][0],self.accuracy[1][1]))
self.log("accuracy (in pixels): LX=%s, LY=%s, RX=%s, RY=%s" % (self.pxaccuracy[0][0],self.pxaccuracy[0][1],self.pxaccuracy[1][0],self.pxaccuracy[1][1]))
self.log("precision (RMS noise in pixels): X=%s, Y=%s" % (self.pxdsttresh[0],self.pxdsttresh[1]))
self.log("distance between participant and display: %s cm" % screendist)
self.log("fixation threshold: %s pixels" % self.pxfixtresh)
self.log("speed threshold: %s pixels/ms" % self.pxspdtresh)
self.log("acceleration threshold: %s pixels/ms**2" % self.pxacctresh)
self.log("pygaze calibration report end")
return True
def close(self):
"""Neatly close connection to tracker
arguments
None
returns
Nothing -- saves data and sets self.connected to False
"""
# close connection
self.eyetribe.close()
self.connected = False
def connected(self):
"""Checks if the tracker is connected
arguments
None
returns
connected -- True if connection is established, False if not;
sets self.connected to the same value
"""
res = self.eyetribe._tracker.get_trackerstate()
if res == 0:
self.connected = True
else:
self.connected = False
return self.connected
def drift_correction(self, pos=None, fix_triggered=False):
"""Performs a drift check
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
fix_triggered -- Boolean indicating if drift check should be
performed based on gaze position (fix_triggered
= True) or on spacepress (fix_triggered =
False) (default = False)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
self.draw_drift_correction_target(pos[0], pos[1])
pressed = False
while not pressed:
pressed, presstime = self.kb.get_key()
if pressed:
if pressed == 'escape' or pressed == 'q':
print("libeyetribe.EyeTribeTracker.drift_correction: 'q' or 'escape' pressed")
return self.calibrate()
gazepos = self.sample()
if ((gazepos[0]-pos[0])**2 + (gazepos[1]-pos[1])**2)**0.5 < self.pxerrdist:
return True
else:
self.errorbeep.play()
return False
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.screen.clear()
self.screen.draw_fixation(fixtype='dot', colour=FGC, pos=(x,y), pw=0,
diameter=12)
self.disp.fill(self.screen)
self.disp.show()
def draw_calibration_target(self, x, y):
self.draw_drift_correction_target(x, y)
def fix_triggered_drift_correction(self, pos=None, min_samples=10, max_dev=60, reset_threshold=30):
"""Performs a fixation triggered drift correction by collecting
a number of samples and calculating the average distance from the
fixation position
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
min_samples -- minimal amount of samples after which an
average deviation is calculated (default = 10)
max_dev -- maximal deviation from fixation in pixels
(default = 60)
reset_threshold -- if the horizontal or vertical distance in
pixels between two consecutive samples is
larger than this threshold, the sample
collection is reset (default = 30)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
self.draw_drift_correction_target(pos[0], pos[1])
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key()[0] in ['escape','q']:
print("libeyetribe.EyeTribeTracker.fix_triggered_drift_correction: 'q' or 'escape' pressed")
return self.calibrate()
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0]) ** 2 + (avg_y - pos[1]) ** 2)**0.5
if d < max_dev:
return True
else:
lx = []
ly = []
def get_eyetracker_clock_async(self):
"""Not supported for EyeTribeTracker (yet)"""
print("function not supported yet")
def log(self, msg):
"""Writes a message to the log file
arguments
ms -- a string to include in the log file
returns
Nothing -- uses native log function of iViewX to include a line
in the log file
"""
self.eyetribe.log_message(msg)
def log_var(self, var, val):
"""Writes a variable to the log file
arguments
var -- variable name
val -- variable value
returns
Nothing -- uses native log function of iViewX to include a line
in the log file in a "var NAME VALUE" layout
"""
msg = "var %s %s" % (var, val)
self.log(msg)
def prepare_drift_correction(self, pos):
"""Not supported for EyeTribeTracker (yet)"""
print("function not supported yet")
def pupil_size(self):
"""Return pupil size
arguments
None
returns
pupil size -- returns pupil diameter for the eye that is currently
being tracked (as specified by self.eye_used) or -1
when no data is obtainable
"""
# get newest pupil size
ps = self.eyetribe.pupil_size()
# invalid data
if ps == None:
return -1
# check if the new pupil size is the same as the previous
if ps != self.prevps:
# update the pupil size
self.prevps = copy.copy(ps)
return self.prevps
def sample(self):
"""Returns newest available gaze position
arguments
None
returns
sample -- an (x,y) tuple or a (-1,-1) on an error
"""
# get newest sample
s = self.eyetribe.sample()
# invalid data
if s == (None,None):
return (-1,-1)
# check if the new sample is the same as the previous
if s != self.prevsample:
# update the current sample
self.prevsample = copy.copy(s)
return self.prevsample
def send_command(self, cmd):
"""Sends a command to the eye tracker
arguments
cmd -- the command to be sent to the EyeTribe, which should
be a list with the following information:
[category, request, values]
returns
Nothing
"""
self.eyetribe._connection.request(cmd)
def start_recording(self):
"""Starts recording eye position
arguments
None
returns
Nothing -- sets self.recording to True when recording is
successfully started
"""
self.eyetribe.start_recording()
self.recording = True
def status_msg(self, msg):
"""Not supported for EyeTribeTracker (yet)"""
print("function not supported yet")
def stop_recording(self):
"""Stop recording eye position
arguments
None
returns
Nothing -- sets self.recording to False when recording is
successfully started
"""
self.eyetribe.stop_recording()
self.recording = False
def set_detection_type(self, eventdetection):
"""Set the event detection type to either PyGaze algorithms, or
native algorithms as provided by the manufacturer (only if
available: detection type will default to PyGaze if no native
functions are available)
arguments
eventdetection -- a string indicating which detection type
should be employed: either 'pygaze' for
PyGaze event detection algorithms or
'native' for manufacturers algorithms (only
if available; will default to 'pygaze' if no
native event detection is available)
returns -- detection type for saccades, fixations and
blinks in a tuple, e.g.
('pygaze','native','native') when 'native'
was passed, but native detection was not
available for saccade detection
"""
if eventdetection in ['pygaze','native']:
self.eventdetection = eventdetection
return ('pygaze','pygaze','pygaze')
def wait_for_event(self, event):
"""Waits for event
arguments
event -- an integer event code, one of the following:
3 = STARTBLINK
4 = ENDBLINK
5 = STARTSACC
6 = ENDSACC
7 = STARTFIX
8 = ENDFIX
returns
outcome -- a self.wait_for_* method is called, depending on the
specified event; the return values of corresponding
method are returned
"""
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception("Error in libsmi.SMItracker.wait_for_event: eventcode %s is not supported" % event)
return outcome
def wait_for_blink_end(self):
"""Waits for a blink end and returns the blink ending time
arguments
None
returns
timestamp -- blink ending time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def wait_for_blink_start(self):
"""Waits for a blink start and returns the blink starting time
arguments
None
returns
timestamp -- blink starting time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed 150 ms
if clock.get_time()-t0 >= 150:
# return timestamp of blink start
return t0
def wait_for_fixation_end(self):
"""Returns time and gaze position when a fixation has ended;
function assumes that a 'fixation' has ended when a deviation of
more than self.pxfixtresh from the initial fixation position has
been detected (self.pxfixtresh is created in self.calibration,
based on self.fixtresh, a property defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer fixation detection; \
PyGaze algorithm will be used")
# # # # #
# PyGaze method
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_fixation_start(self):
"""Returns starting time and position when a fixation is started;
function assumes a 'fixation' has started when gaze position
remains reasonably stable (i.e. when most deviant samples are
within self.pxfixtresh) for five samples in a row (self.pxfixtresh
is created in self.calibration, based on self.fixtresh, a property
defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a fixation start
# detection built into their API (only ending)
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer fixation detection; \
PyGaze algorithm will be used")
# # # # #
# PyGaze method
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a saccade is
ended; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos, endpos -- endtime in milliseconds (from
expbegintime); startpos and endpos
are (x,y) gaze position tuples
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0]-spos[0])**2 + (prevpos[1]-spos[1])**2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1-t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0]-prevpos[0])**2 + (newpos[1]-prevpos[1])**2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1-t0)
# calculate acceleration
a = (v1-v0) / (t1-t0) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1*self.pxacctresh and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a saccade is
started; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos -- endtime in milliseconds (from expbegintime);
startpos is an (x,y) gaze position tuple
"""
# # # # #
# EyeTribe method
if self.eventdetection == 'native':
# print warning, since EyeTribe does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but EyeTribe does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0]-prevpos[0]; sy = newpos[1]-prevpos[1]
if (sx/self.pxdsttresh[0])**2 + (sy/self.pxdsttresh[1])**2 > self.weightdist: # weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1-t0)
# calculate acceleration
a = (v1-v0) / (t1-t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def is_valid_sample(self, gazepos):
"""Checks if the sample provided is valid, based on EyeTribe specific
criteria (for internal use)
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (None,None) or gazepos == (-1,-1):
return False
# in any other case, the sample is valid
return True
class Dummy(DumbDummy):
"""A dummy class to run experiments in dummy mode, where eye movements are simulated by the mouse"""
def __init__(self, display):
"""Initiates an eyetracker dummy object, that simulates gaze position using the mouse
arguments
display -- a pygaze display.Display instance
keyword arguments
None
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, Dummy)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
self.recording = False
self.blinking = False
self.bbpos = (settings.DISPSIZE[0] / 2, settings.DISPSIZE[1] / 2)
self.resolution = settings.DISPSIZE[:]
self.simulator = Mouse(disptype=settings.DISPTYPE,
mousebuttonlist=None,
timeout=2,
visible=False)
self.kb = Keyboard(disptype=settings.DISPTYPE,
keylist=None,
timeout=None)
self.angrybeep = Sound(osc='saw',
freq=100,
length=100,
attack=0,
decay=0,
soundfile=None)
self.display = display
self.screen = Screen(disptype=settings.DISPTYPE, mousevisible=False)
def calibrate(self):
"""Dummy calibration"""
print("Calibration would now take place")
clock.pause(1000)
def drift_correction(self, pos=None, fix_triggered=False):
"""Dummy drift correction"""
print("Drift correction would now take place")
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
if pos == None:
pos = settings.DISPSIZE[0] / 2, settings.DISPSIZE[1] / 2
# show mouse
self.simulator.set_visible(visible=True)
# show fixation dot
self.draw_drift_correction_target(pos[0], pos[1])
# perform drift check
errdist = 60 # pixels (on a 1024x768px and 39.9x29.9cm monitor at 67 cm, this is about 2 degrees of visual angle)
pressed = None
while True:
# check for keyboard input
pressed, presstime = self.kb.get_key(
keylist=['q', 'escape', 'space'], timeout=1)
# quit key
if pressed in ['q', 'escape']:
# hide mouse
self.simulator.set_visible(visible=False)
return False
# space bar
elif pressed == 'space':
# get sample
gazepos = self.sample()
# sample is close enough to fixation dot
if ((gazepos[0] - pos[0])**2 +
(gazepos[1] - pos[1])**2)**0.5 < errdist:
# hide mouse
self.simulator.set_visible(visible=False)
return True
# sample is NOT close enough to fixation dot
else:
# show discontent
self.angrybeep.play()
def fix_triggered_drift_correction(self,
pos=None,
min_samples=30,
max_dev=60,
reset_threshold=10):
"""Dummy drift correction (fixation triggered)"""
print("Drift correction (fixation triggered) would now take place")
if pos == None:
pos = settings.DISPSIZE[0] / 2, settings.DISPSIZE[1] / 2
# show mouse
self.simulator.set_visible(visible=True)
# show fixation dot
self.draw_drift_correction_target(pos[0], pos[1])
while True:
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key(keylist=["escape", "q"],
timeout=0)[0] != None:
self.recording = False
print(
"libeyetracker.libeyetracker.fix_triggered_drift_correction(): 'q' pressed"
)
self.simulator.set_visible(visible=False)
return False
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold
or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
# check if samples are within max. deviation
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0])**2 + (avg_y - pos[1])**2)**0.5
if d < max_dev:
self.simulator.set_visible(visible=False)
return True
else:
lx = []
ly = []
def start_recording(self):
"""Dummy for starting recording, prints what would have been the recording start"""
self.simulator.set_visible(visible=True)
dumrectime = clock.get_time()
self.recording = True
print("Recording would have started at: " + str(dumrectime))
def stop_recording(self):
"""Dummy for stopping recording, prints what would have been the recording end"""
self.simulator.set_visible(visible=False)
dumrectime = clock.get_time()
self.recording = False
print("Recording would have stopped at: " + str(dumrectime))
def close(self):
"""Dummy for closing connection with eyetracker, prints what would have been connection closing time"""
if self.recording:
self.stop_recording()
closetime = clock.get_time()
print("eyetracker connection would have closed at: " + str(closetime))
def pupil_size(self):
"""Returns dummy pupil size"""
return 19
def sample(self):
"""Returns simulated gaze position (=mouse position)"""
if self.blinking:
if self.simulator.get_pressed()[2]: # buttondown
self.simulator.set_pos(pos=(
self.bbpos[0],
self.resolution[1])) # set position to blinking position
elif not self.simulator.get_pressed()[2]: # buttonup
self.simulator.set_pos(
pos=self.bbpos) # set position to position before blinking
self.blinking = False # 'blink' stopped
elif not self.blinking:
if self.simulator.get_pressed()[2]: # buttondown
self.blinking = True # 'blink' started
self.bbpos = self.simulator.get_pos(
) # position before blinking
self.simulator.set_pos(pos=(
self.bbpos[0],
self.resolution[1])) # set position to blinking position
return self.simulator.get_pos()
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a simulated saccade is started"""
# function assumes that a 'saccade' has been started when a deviation of more than
# maxerr from the initial 'gaze' position has been detected (using Pythagoras, ofcourse)
spos = self.sample() # starting position
maxerr = 3 # pixels
while True:
npos = self.sample() # get newest sample
if ((spos[0] - npos[0])**2 +
(spos[1] - npos[1])**2)**0.5 > maxerr: # Pythagoras
break
return clock.get_time(), spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a simulated saccade is ended"""
# function assumes that a 'saccade' has ended when 'gaze' position remains reasonably
# (i.e.: within maxerr) stable for five samples
# for saccade start algorithm, see wait_for_fixation_start
stime, spos = self.wait_for_saccade_start()
maxerr = 3 # pixels
# wait for reasonably stable position
xl = [] # list for last five samples (x coordinate)
yl = [] # list for last five samples (y coordinate)
moving = True
while moving:
# check positions
npos = self.sample()
xl.append(npos[0]) # add newest sample
yl.append(npos[1]) # add newest sample
if len(xl) == 5:
# check if deviation is small enough
if max(xl) - min(xl) < maxerr and max(yl) - min(yl) < maxerr:
moving = False
# remove oldest sample
xl.pop(0)
yl.pop(0)
# wait for a bit, to avoid immediately returning (runs go faster than mouse moves)
clock.pause(10)
return clock.get_time(), spos, (xl[len(xl) - 1], yl[len(yl) - 1])
def wait_for_fixation_start(self):
"""Returns starting time and position when a simulated fixation is started"""
# function assumes a 'fixation' has started when 'gaze' position remains reasonably
# stable for five samples in a row (same as saccade end)
maxerr = 3 # pixels
# wait for reasonably stable position
xl = [] # list for last five samples (x coordinate)
yl = [] # list for last five samples (y coordinate)
moving = True
while moving:
npos = self.sample()
xl.append(npos[0]) # add newest sample
yl.append(npos[1]) # add newest sample
if len(xl) == 5:
# check if deviation is small enough
if max(xl) - min(xl) < maxerr and max(yl) - min(yl) < maxerr:
moving = False
# remove oldest sample
xl.pop(0)
yl.pop(0)
# wait for a bit, to avoid immediately returning (runs go faster than mouse moves)
clock.pause(10)
return clock.get_time(), (xl[len(xl) - 1], yl[len(yl) - 1])
def wait_for_fixation_end(self):
"""Returns time and gaze position when a simulated fixation is ended"""
# function assumes that a 'fixation' has ended when a deviation of more than maxerr
# from the initial 'fixation' position has been detected (using Pythagoras, ofcourse)
stime, spos = self.wait_for_fixation_start()
maxerr = 3 # pixels
while True:
npos = self.sample() # get newest sample
if ((spos[0] - npos[0])**2 +
(spos[1] - npos[1])**2)**0.5 > maxerr: # Pythagoras
break
return clock.get_time(), spos
def wait_for_blink_start(self):
"""Returns starting time and position of a simulated blink (mousebuttondown)"""
# blinks are simulated with mouseclicks: a right mouseclick simulates the closing
# of the eyes, a mousebuttonup the opening.
while not self.blinking:
pos = self.sample()
return clock.get_time(), pos
def wait_for_blink_end(self):
"""Returns ending time and position of a simulated blink (mousebuttonup)"""
# blinks are simulated with mouseclicks: a right mouseclick simulates the closing
# of the eyes, a mousebuttonup the opening.
# wait for blink start
while not self.blinking:
spos = self.sample()
# wait for blink end
while self.blinking:
epos = self.sample()
return clock.get_time(), epos
def set_draw_drift_correction_target_func(self, func):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.draw_drift_correction_target = func
# ***
#
# Internal functions below
#
# ***
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.screen.clear()
self.screen.draw_fixation(fixtype='dot', colour=settings.FGC, \
pos=(x,y), pw=0, diameter=12)
self.display.fill(self.screen)
self.display.show()
def __init__(self, display, logfile=LOGFILE, eventdetection=EVENTDETECTION, \
saccade_velocity_threshold=35, saccade_acceleration_threshold=9500, \
**args):
"""Initializes the EyeTribeTracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
logfile -- logfile name (string value); note that this is the
name for the eye data log file (default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, EyeTribeTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = DISPSIZE # display size in pixels
self.screensize = SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw',freq=100, length=100)
# output file properties
self.outputfile = logfile
# eye tracker properties
self.connected = False
self.recording = False
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = 30 # initial error in pixels
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1,-1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# connect to the tracker
self.eyetribe = EyeTribe(logfilename=logfile)
# get info on the sample rate
self.samplerate = self.eyetribe._samplefreq
self.sampletime = 1000.0 * self.eyetribe._intsampletime
# initiation report
self.log("pygaze initiation report start")
self.log("display resolution: %sx%s" % (self.dispsize[0],self.dispsize[1]))
self.log("display size in cm: %sx%s" % (self.screensize[0],self.screensize[1]))
self.log("samplerate: %.2f Hz" % self.samplerate)
self.log("sampletime: %.2f ms" % self.sampletime)
self.log("fixation threshold: %s degrees" % self.fixtresh)
self.log("speed threshold: %s degrees/second" % self.spdtresh)
self.log("acceleration threshold: %s degrees/second**2" % self.accthresh)
self.log("pygaze initiation report end")
kb = Keyboard()
# Initialise the EyeTracker and let it know which Display instance to use by
# passing it to the EyeTracker.
tracker = EyeTracker(disp)
# Create a Logfile instance that keeps track of when videos start.
log = Logfile()
# Write a header to the log file.
log.write(['date', 'time', 'trialnr', 'video', 'timestamp'])
# # # # #
# SCREENS
# Create a screen to show instructions on.
textscr = Screen()
textscr.draw_text("Press any key to start the next video.", fontsize=24)
# Create a screen to show images on. This will be the screen that we will use
# to display each video frame.
stimscr = Screen()
# # # # #
# PLAY VIDEOS
# Calibrate the eye tracker.
tracker.calibrate()
# Randomise the list of videos. Remove this line if you want the videos to be
# displayed in alphabetical order.
random.shuffle(VIDEOS)
from pygaze.display import Display
from pygaze.screen import Screen
from pygaze.eyetracker import EyeTracker
import pygaze.libtime as timer
disp = Display()
scr = Screen()
scr.draw_text("Preparing experiment...", fontsize=20)
disp.fill(scr)
disp.show()
tracker = EyeTracker(disp)
tracker.calibrate()
tracker.start_recording()
t0 = timer.get_time()
while timer.get_time() - t0 < 5000:
gazepos = tracker.sample()
scr.clear()
scr.draw_fixation(fixtype='dot', pos=gazepos)
disp.fill(scr)
disp.show()
tracker.stop_recording()
tracker.close()
disp.close()
# set up function argument types and return type XInputSetState = xinput.XInputSetState XInputSetState.argtypes = [ctypes.c_uint, ctypes.POINTER(XINPUT_VIBRATION)] XInputSetState.restype = ctypes.c_uint # define helper function def set_vibration(controller, left_motor, right_motor): vibration = XINPUT_VIBRATION(int(left_motor * 65535), int(right_motor * 65535)) XInputSetState(controller, ctypes.byref(vibration)) # # # # # # PYGAZE INSTANCES # visual disp = Display() scr = Screen() # input js = Joystick() # # # # # # RUN # run until a minute has passed t0 = timer.get_time() t1 = timer.get_time() text = "Test the joystick!" while t1 - t0 < 60000: # get joystick input event, value, t1 = js.get_joyinput(timeout=10) # update text
# # # # # # directory stuff DIR = os.path.split(os.path.abspath(__file__))[0] image_file = os.path.join(DIR, 'www.google.co.uk_(Pixel 2).png') # # # # # # create instances # initialize the display disp = Display() # initialize a screen scr = Screen() # initialize an EyeTracker tracker = EyeTracker(disp) # initialize a keyboard kb = Keyboard(keylist=['space'],timeout=None) # initialize a Timer timer = Time() # create a new logfile log = Logfile(filename="test") log.write(["x_pos","y_pos", "time"])
from pygaze.display import Display import pygaze.libtime as timer from pygaze.screen import Screen from constants import * fixscreen = Screen() fixscreen.draw_fixation(fixtype='dot') disp = Display() timer.pause(2000) disp.close()
# -*- coding: utf-8 -*-
"""
Created on Thu Nov 10 13:29:48 2016
@author: adam
"""
from pygaze.display import Display
from pygaze.screen import Screen
import pygaze.libtime as timer
# disp = Window(size=DISPSIZE, units='pix', fullscr=True)
disp = Display()
fixscreen = Screen()
fixscreen.draw_fixation(fixtype='dot')
imgscreen = Screen()
imgscreen.draw_image('/home/adam/Desktop/experiment0/Example.png')
disp.fill(fixscreen)
disp.show()
timer.pause(1000)
disp.fill(imgscreen)
disp.show()
timer.pause(2000)
disp.close()
def __init__(self,
display,
resolution=DISPSIZE,
data_file=LOGFILENAME + ".edf",
fg_color=FGC,
bg_color=BGC,
eventdetection=EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
force_drift_correct=True,
pupil_size_mode=EYELINKPUPILSIZEMODE,
**args):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# try to import copy docstring (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, libeyelink)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
global _eyelink
# Make sure that we have a valid data file. The local_data_file may
# contain a folder. The eyelink_data_file is only a basename, i.e.
# without folder. The eyelink_data_file must be at most eight characters
# and end with a `.edf` extension.
self.local_data_file = data_file
self.eyelink_data_file = os.path.basename(data_file)
stem, ext = os.path.splitext(self.eyelink_data_file)
if len(stem) > 8 or ext.lower() != '.edf':
raise Exception(
"The EyeLink cannot handle filenames longer than eight "
"characters (excluding '.edf' extension).")
# properties
self.display = display
self.fontsize = 18
self.scr = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=["escape", "q"], timeout=1)
self.resolution = resolution
self.recording = False
self.saccade_velocity_treshold = saccade_velocity_threshold
self.saccade_acceleration_treshold = saccade_acceleration_threshold
self.eye_used = None
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.pupil_size_mode = pupil_size_mode
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
# degrees; maximal distance from fixation start (if gaze wanders beyond
# this, fixation has stopped)
self.fixtresh = 1.5
# milliseconds; amount of time gaze has to linger within self.fixtresh
# to be marked as a fixation
self.fixtimetresh = 100
# degrees per second; saccade velocity threshold
self.spdtresh = self.saccade_velocity_treshold
# degrees per second**2; saccade acceleration threshold
self.accthresh = self.saccade_acceleration_treshold
self.set_detection_type(eventdetection)
# weighted distance, used for determining whether a movement is due to
# measurement error (1 is ok, higher is more conservative and will
# result in only larger saccades to be detected)
self.weightdist = 10
# distance between participant and screen in cm
self.screendist = SCREENDIST
# distance between participant and screen in cm
self.screensize = SCREENSIZE
self.pixpercm = (self.resolution[0]/float(self.screensize[0]) + \
self.resolution[1]/float(self.screensize[1])) / 2.0
# only initialize eyelink once
if _eyelink == None:
try:
_eyelink = pylink.EyeLink()
except:
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to "
"connect to the tracker!")
# determine software version of tracker
self.tracker_software_ver = 0
self.eyelink_ver = pylink.getEYELINK().getTrackerVersion()
if self.eyelink_ver == 3:
tvstr = pylink.getEYELINK().getTrackerVersionString()
vindex = tvstr.find("EYELINK CL")
self.tracker_software_ver = int(float(tvstr[(vindex + \
len("EYELINK CL")):].strip()))
if self.eyelink_ver == 1:
self.eyelink_model = 'EyeLink I'
elif self.eyelink_ver == 2:
self.eyelink_model = 'EyeLink II'
elif self.eyelink_ver == 3:
self.eyelink_model = 'EyeLink 1000'
else:
self.eyelink_model = 'EyeLink (model unknown)'
# Open graphics
self.eyelink_graphics = EyelinkGraphics(self, _eyelink)
pylink.openGraphicsEx(self.eyelink_graphics)
# Optionally force drift correction. For some reason this must be done
# as (one of) the first things, otherwise a segmentation fault occurs.
if force_drift_correct:
self.send_command('driftcorrect_cr_disable = OFF')
# Set pupil-size mode
if self.pupil_size_mode == 'area':
pylink.getEYELINK().setPupilSizeDiameter(False)
elif self.pupil_size_mode == 'diameter':
pylink.getEYELINK().setPupilSizeDiameter(True)
else:
raise Exception(
"pupil_size_mode should be 'area' or 'diameter', not %s" \
% self.pupil_size_mode)
pylink.getEYELINK().openDataFile(self.eyelink_data_file)
pylink.flushGetkeyQueue()
pylink.getEYELINK().setOfflineMode()
# notify eyelink of display resolution
self.send_command("screen_pixel_coords = 0 0 %d %d" % \
(self.resolution[0], self.resolution[1]))
# get some configuration stuff
if self.eyelink_ver >= 2:
self.send_command("select_parser_configuration 0")
if self.eyelink_ver == 2: # turn off scenelink camera stuff
self.send_command("scene_camera_gazemap = NO")
# set EDF file contents (this specifies which data is written to the EDF
# file)
self.send_command(
"file_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,MESSAGE,BUTTON"
)
if self.tracker_software_ver >= 4:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS,HTARGET"
)
else:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS")
# set link data (this specifies which data is sent through the link and
# thus can be used in gaze contingent displays)
self.send_command(
"link_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,BUTTON")
if self.tracker_software_ver >= 4:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS,HTARGET"
)
else:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS")
# not quite sure what this means (according to Sebastiaan Mathot, it
# might be the button that is used to end drift correction?)
self.send_command("button_function 5 'accept_target_fixation'")
if not self.connected():
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to connect "
"to the eyetracker!")
class SMItracker(BaseEyeTracker):
"""A class for SMI eye tracker objects"""
def __init__(self, display, ip='127.0.0.1', sendport=4444, receiveport= \
5555, logfile=LOGFILE, eventdetection=EVENTDETECTION, \
saccade_velocity_threshold=35, saccade_acceleration_threshold=9500, \
**args):
"""Initializes the SMItracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
ip -- internal ip address for iViewX (default =
'127.0.0.1')
sendport -- port number for iViewX sending (default = 4444)
receiveport -- port number for iViewX receiving (default = 5555)
logfile -- logfile name (string value); note that this is the
name for the SMI logfile, NOT the .idf file
(default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, SMITracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = DISPSIZE # display size in pixels
self.screensize = SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw',freq=100, length=100)
# output file properties
self.outputfile = logfile
self.description = "experiment" # TODO: EXPERIMENT NAME
self.participant = "participant" # TODO: PP NAME
# eye tracker properties
self.connected = False
self.recording = False
self.eye_used = 0 # 0=left, 1=right, 2=binocular
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.errdist = 2 # degrees; maximal error for drift correction
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1,-1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# set logger
res = iViewXAPI.iV_SetLogger(c_int(1), c_char_p(logfile + '_SMILOG.txt'))
if res != 1:
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.__init__: failed to set logger; %s" % err)
# first logger argument is for logging type (I'm guessing these are decimal bit codes)
# LOG status bitcode
# 1 = LOG_LEVEL_BUG 00001
# 2 = LOG_LEVEL_iV_FCT 00010
# 4 = LOG_LEVEL_ETCOM 00100
# 8 = LOG_LEVEL_ALL 01000
# 16 = LOG_LEVEL_IV_COMMAND 10000
# these can be used together, using a bitwise or, e.g.: 1|2|4 (bitcode 00111)
# connect to iViewX
res = iViewXAPI.iV_Connect(c_char_p(ip), c_int(sendport), c_char_p(ip), c_int(receiveport))
if res == 1:
res = iViewXAPI.iV_GetSystemInfo(byref(systemData))
self.samplerate = systemData.samplerate
self.sampletime = 1000.0 / self.samplerate
if res != 1:
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.__init__: failed to get system information; %s" % err)
# handle connection errors
else:
self.connected = False
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.__init__: establishing connection failed; %s" % err)
# initiation report
self.log("pygaze initiation report start")
self.log("experiment: %s" % self.description)
self.log("participant: %s" % self.participant)
self.log("display resolution: %sx%s" % (self.dispsize[0],self.dispsize[1]))
self.log("display size in cm: %sx%s" % (self.screensize[0],self.screensize[1]))
self.log("samplerate: %s Hz" % self.samplerate)
self.log("sampletime: %s ms" % self.sampletime)
self.log("fixation threshold: %s degrees" % self.fixtresh)
self.log("speed threshold: %s degrees/second" % self.spdtresh)
self.log("acceleration threshold: %s degrees/second**2" % self.accthresh)
self.log("pygaze initiation report end")
def calibrate(self, calibrate=True, validate=True):
"""Calibrates the eye tracking system
arguments
None
keyword arguments
calibrate -- Boolean indicating if calibration should be
performed (default = True)
validate -- Boolean indicating if validation should be performed
(default = True)
returns
success -- returns True if calibration succeeded, or False if
not; in addition a calibration log is added to the
log file and some properties are updated (i.e. the
thresholds for detection algorithms)
"""
# TODO:
# add feedback for calibration (e.g. with iV_GetAccuracyImage (struct ImageStruct * imageData) for accuracy and iV_GetEyeImage for cool eye pictures)
# example: res = iViewXAPI.iV_GetEyeImage(byref(imageData))
# ImageStruct has four data fields:
# imageHeight -- int vertical size (px)
# imageWidth -- int horizontal size (px)
# imageSize -- int image data size (byte)
# imageBuffer -- pointer to image data (I have NO idea what format this is in)
# configure calibration (NOT starting it)
calibrationData = CCalibration(9, 1, 0, 1, 1, 0, 127, 1, 15, b"") # (method (i.e.: number of points), visualization, display, speed, auto, fg, bg, shape, size, filename)
# setup calibration
res = iViewXAPI.iV_SetupCalibration(byref(calibrationData))
if res != 1:
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.calibrate: failed to setup calibration; %s" % err)
# calibrate
cres = iViewXAPI.iV_Calibrate()
# validate if calibration returns succes
if cres == 1:
cerr = None
vres = iViewXAPI.iV_Validate()
# handle validation errors
if vres != 1:
verr = errorstring(vres)
else:
verr = None
## # TEST #
## res = iViewXAPI.iV_GetAccuracyImage(byref(imageData))
## self.log("IMAGEBUFFERSTART")
## self.log(imageData.imageBuffer)
## self.log("IMAGEBUFFERSTOP")
## print("Image height: %s, image width: %s, image size: %s" % (imageData.imageHeight,imageData.imageWidth, imageData.imageSize))
## print imageData.imageBuffer
## ########
# handle calibration errors
else:
cerr = errorstring(cres)
# return succes
if cerr == None:
print("libsmi.SMItracker.calibrate: calibration was succesful")
if verr == None:
print("libsmi.SMItracker.calibrate: validation was succesful")
# present instructions
self.disp.fill() # clear display
self.screen.draw_text(text="Noise calibration: please look at the dot\n\n(press space to start)", pos=(self.dispsize[0]/2, int(self.dispsize[1]*0.2)), center=True)
self.screen.draw_fixation(fixtype='dot')
self.disp.fill(self.screen)
self.disp.show()
self.screen.clear() # clear screen again
# wait for spacepress
self.kb.get_key(keylist=['space'], timeout=None)
# show fixation
self.disp.fill()
self.screen.draw_fixation(fixtype='dot')
self.disp.fill(self.screen)
self.disp.show()
self.screen.clear()
# wait for a bit, to allow participant to fixate
clock.pause(500)
# get samples
sl = [self.sample()] # samplelist, prefilled with 1 sample to prevent sl[-1] from producing an error; first sample will be ignored for RMS calculation
t0 = clock.get_time() # starting time
while clock.get_time() - t0 < 1000:
s = self.sample() # sample
if s != sl[-1] and s != (-1,-1) and s != (0,0):
sl.append(s)
# calculate RMS noise
Xvar = []
Yvar = []
for i in range(2,len(sl)):
Xvar.append((sl[i][0]-sl[i-1][0])**2)
Yvar.append((sl[i][1]-sl[i-1][1])**2)
XRMS = (sum(Xvar) / len(Xvar))**0.5
YRMS = (sum(Yvar) / len(Yvar))**0.5
self.pxdsttresh = (XRMS, YRMS)
# calculate pixels per cm
pixpercm = (self.dispsize[0]/float(self.screensize[0]) + self.dispsize[1]/float(self.screensize[1])) / 2
# get accuracy
res = 0; i = 0
while res != 1 and i < self.maxtries: # multiple tries, in case no (valid) sample is available
res = iViewXAPI.iV_GetAccuracy(byref(accuracyData),0) # 0 is for 'no visualization'
i += 1
clock.pause(int(self.sampletime)) # wait for sampletime
if res == 1:
self.accuracy = ((accuracyData.deviationLX,accuracyData.deviationLY), (accuracyData.deviationLX,accuracyData.deviationLY)) # dsttresh = (left tuple, right tuple); tuple = (horizontal deviation, vertical deviation) in degrees of visual angle
else:
err = errorstring(res)
print("WARNING libsmi.SMItracker.calibrate: failed to obtain accuracy data; %s" % err)
self.accuracy = ((2,2),(2,2))
print("libsmi.SMItracker.calibrate: As an estimate, the intersample distance threshhold was set to it's default value of 2 degrees")
# get distance from screen to eyes (information from tracker)
res = 0; i = 0
while res != 1 and i < self.maxtries: # multiple tries, in case no (valid) sample is available
res = iViewXAPI.iV_GetSample(byref(sampleData))
i += 1
clock.pause(int(self.sampletime)) # wait for sampletime
if res == 1:
screendist = sampleData.leftEye.eyePositionZ / 10.0 # eyePositionZ is in mm; screendist is in cm
else:
err = errorstring(res)
print("WARNING libsmi.SMItracker.calibrate: failed to obtain screen distance; %s" % err)
screendist = SCREENDIST
print("libsmi.SMItracker.calibrate: As an estimate, the screendistance was set to it's default value of 57 cm")
# calculate thresholds based on tracker settings
self.pxerrdist = deg2pix(screendist, self.errdist, pixpercm)
self.pxfixtresh = deg2pix(screendist, self.fixtresh, pixpercm)
self.pxaccuracy = ((deg2pix(screendist, self.accuracy[0][0], pixpercm),deg2pix(screendist, self.accuracy[0][1], pixpercm)), (deg2pix(screendist, self.accuracy[1][0], pixpercm),deg2pix(screendist, self.accuracy[1][1], pixpercm)))
self.pxspdtresh = deg2pix(screendist, self.spdtresh/1000.0, pixpercm) # in pixels per millisecond
self.pxacctresh = deg2pix(screendist, self.accthresh/1000.0, pixpercm) # in pixels per millisecond**2
# calibration report
self.log("pygaze calibration report start")
self.log("accuracy (degrees): LX=%s, LY=%s, RX=%s, RY=%s" % (self.accuracy[0][0],self.accuracy[0][1],self.accuracy[1][0],self.accuracy[1][1]))
self.log("accuracy (in pixels): LX=%s, LY=%s, RX=%s, RY=%s" % (self.pxaccuracy[0][0],self.pxaccuracy[0][1],self.pxaccuracy[1][0],self.pxaccuracy[1][1]))
self.log("precision (RMS noise in pixels): X=%s, Y=%s" % (self.pxdsttresh[0],self.pxdsttresh[1]))
self.log("distance between participant and display: %s cm" % screendist)
self.log("fixation threshold: %s pixels" % self.pxfixtresh)
self.log("speed threshold: %s pixels/ms" % self.pxspdtresh)
self.log("acceleration threshold: %s pixels/ms**2" % self.pxacctresh)
self.log("pygaze calibration report end")
return True
# validation error
else:
print("WARNING libsmi.SMItracker.calibrate: validation was unsuccesful %s" % verr)
return False
# calibration error
else:
print("WARNING libsmi.SMItracker.calibrate: calibration was unsuccesful; %s" % cerr)
return False
def close(self):
"""Neatly close connection to tracker
arguments
None
returns
Nothing -- saves data and sets self.connected to False
"""
# save data
res = iViewXAPI.iV_SaveData(str(self.outputfile), str(self.description), str(self.participant), 1)
if res != 1:
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.close: failed to save data; %s" % err)
# close connection
iViewXAPI.iV_Disconnect()
self.connected = False
def connected(self):
"""Checks if the tracker is connected
arguments
None
returns
connected -- True if connection is established, False if not;
sets self.connected to the same value
"""
res = iViewXAPI.iV_IsConnected()
if res == 1:
self.connected = True
else:
self.connected = False
return self.connected
def drift_correction(self, pos=None, fix_triggered=False):
"""Performs a drift check
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
fix_triggered -- Boolean indicating if drift check should be
performed based on gaze position (fix_triggered
= True) or on spacepress (fix_triggered =
False) (default = False)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
pressed = False
while not pressed:
pressed, presstime = self.kb.get_key()
if pressed:
if pressed == 'escape' or pressed == 'q':
print("libsmi.SMItracker.drift_correction: 'q' or 'escape' pressed")
return self.calibrate(calibrate=True, validate=True)
gazepos = self.sample()
if ((gazepos[0]-pos[0])**2 + (gazepos[1]-pos[1])**2)**0.5 < self.pxerrdist:
return True
else:
self.errorbeep.play()
return False
def fix_triggered_drift_correction(self, pos=None, min_samples=10, max_dev=60, reset_threshold=30):
"""Performs a fixation triggered drift correction by collecting
a number of samples and calculating the average distance from the
fixation position
arguments
None
keyword arguments
pos -- (x, y) position of the fixation dot or None for
a central fixation (default = None)
min_samples -- minimal amount of samples after which an
average deviation is calculated (default = 10)
max_dev -- maximal deviation from fixation in pixels
(default = 60)
reset_threshold -- if the horizontal or vertical distance in
pixels between two consecutive samples is
larger than this threshold, the sample
collection is reset (default = 30)
returns
checked -- Boolaan indicating if drift check is ok (True)
or not (False); or calls self.calibrate if 'q'
or 'escape' is pressed
"""
if pos == None:
pos = self.dispsize[0] / 2, self.dispsize[1] / 2
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key()[0] in ['escape','q']:
print("libsmi.SMItracker.fix_triggered_drift_correction: 'q' or 'escape' pressed")
return self.calibrate(calibrate=True, validate=True)
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0]) ** 2 + (avg_y - pos[1]) ** 2)**0.5
if d < max_dev:
return True
else:
lx = []
ly = []
def get_eyetracker_clock_async(self):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def log(self, msg):
"""Writes a message to the log file
arguments
ms -- a string to include in the log file
returns
Nothing -- uses native log function of iViewX to include a line
in the log file
"""
res = iViewXAPI.iV_Log(c_char_p(msg))
if res != 1:
err = errorstring(res)
print("WARNING libsmi.SMItracker.log: failed to log message '%s'; %s" % (msg,err))
def log_var(self, var, val):
"""Writes a variable to the log file
arguments
var -- variable name
val -- variable value
returns
Nothing -- uses native log function of iViewX to include a line
in the log file in a "var NAME VALUE" layout
"""
msg = "var %s %s" % (var, val)
res = iViewXAPI.iV_Log(c_char_p(msg))
if res != 1:
err = errorstring(res)
print("WARNING libsmi.SMItracker.log_var: failed to log variable '%s' with value '%s'; %s" % (var,val,err))
def prepare_backdrop(self):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def prepare_drift_correction(self, pos):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def pupil_size(self):
"""Return pupil size
arguments
None
returns
pupil size -- returns pupil diameter for the eye that is currently
being tracked (as specified by self.eye_used) or -1
when no data is obtainable
"""
res = iViewXAPI.iV_GetSample(byref(sampleData))
# if a new sample exists
if res == 1:
# left eye
if self.eye_used == self.left_eye:
ps = sampleData.leftEye.diam
# right eye
else:
ps = sampleData.rightEye.diam
# set prvious pupil size to newest pupil size
self.prevps = ps
return ps
# no new sample available
elif res == 2:
return self.prevps
# invalid data
else:
# print warning to interpreter
err = errorstring(res)
print("WARNING libsmi.SMItracker.pupil_size: failed to obtain sample; %s" % err)
return -1
def sample(self):
"""Returns newest available gaze position
arguments
None
returns
sample -- an (x,y) tuple or a (-1,-1) on an error
"""
res = iViewXAPI.iV_GetSample(byref(sampleData))
if self.eye_used == self.right_eye:
newsample = sampleData.rightEye.gazeX, sampleData.rightEye.gazeY
else:
newsample = sampleData.leftEye.gazeX, sampleData.leftEye.gazeY
if res == 1:
self.prevsample = newsample[:]
return newsample
elif res == 2:
return self.prevsample
else:
err = errorstring(res)
print("WARNING libsmi.SMItracker.sample: failed to obtain sample; %s" % err)
return (-1,-1)
def send_command(self, cmd):
"""Sends a command to the eye tracker
arguments
cmd -- the command (a string value) to be sent to iViewX
returns
Nothing
"""
try:
iViewXAPI.iV_SendCommand(c_char_p(cmd))
except:
raise Exception("Error in libsmi.SMItracker.send_command: failed to send remote command to iViewX (iV_SendCommand might be deprecated)")
def set_backdrop(self):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def set_eye_used(self):
"""Logs the eye_used variable, based on which eye was specified
(if both eyes are being tracked, the left eye is used)
arguments
None
returns
Nothing -- logs which eye is used by calling self.log_var, e.g.
self.log_var("eye_used", "right")
"""
if self.eye_used == self.right_eye:
self.log_var("eye_used", "right")
else:
self.log_var("eye_used", "left")
def start_recording(self):
"""Starts recording eye position
arguments
None
returns
Nothing -- sets self.recording to True when recording is
successfully started
"""
res = 0; i = 0
while res != 1 and i < self.maxtries:
res = iViewXAPI.iV_StartRecording()
i += 1
if res == 1:
self.recording = True
else:
self.recording = False
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.start_recording: %s" % err)
def status_msg(self, msg):
"""Not supported for SMItracker (yet)"""
print("function not supported yet")
def stop_recording(self):
"""Stop recording eye position
arguments
None
returns
Nothing -- sets self.recording to False when recording is
successfully started
"""
res = 0; i = 0
while res != 1 and i < self.maxtries:
res = iViewXAPI.iV_StopRecording()
i += 1
if res == 1:
self.recording = False
else:
self.recording = False
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.stop_recording: %s" % err)
def set_detection_type(self, eventdetection):
"""Set the event detection type to either PyGaze algorithms, or
native algorithms as provided by the manufacturer (only if
available: detection type will default to PyGaze if no native
functions are available)
arguments
eventdetection -- a string indicating which detection type
should be employed: either 'pygaze' for
PyGaze event detection algorithms or
'native' for manufacturers algorithms (only
if available; will default to 'pygaze' if no
native event detection is available)
returns -- detection type for saccades, fixations and
blinks in a tuple, e.g.
('pygaze','native','native') when 'native'
was passed, but native detection was not
available for saccade detection
"""
if eventdetection in ['pygaze','native']:
self.eventdetection = eventdetection
return ('pygaze','native','pygaze')
def wait_for_event(self, event):
"""Waits for event
arguments
event -- an integer event code, one of the following:
3 = STARTBLINK
4 = ENDBLINK
5 = STARTSACC
6 = ENDSACC
7 = STARTFIX
8 = ENDFIX
returns
outcome -- a self.wait_for_* method is called, depending on the
specified event; the return values of corresponding
method are returned
"""
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception("Error in libsmi.SMItracker.wait_for_event: eventcode %s is not supported" % event)
return outcome
def wait_for_blink_end(self):
"""Waits for a blink end and returns the blink ending time
arguments
None
returns
timestamp -- blink ending time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = True
# loop while there is a blink
while blinking:
# get newest sample
gazepos = self.sample()
# check if it's valid
if self.is_valid_sample(gazepos):
# if it is a valid sample, blinking has stopped
blinking = False
# return timestamp of blink end
return clock.get_time()
def wait_for_blink_start(self):
"""Waits for a blink start and returns the blink starting time
arguments
None
returns
timestamp -- blink starting time in milliseconds, as
measured from experiment begin time
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer blink detection; PyGaze algorithm \
will be used")
# # # # #
# PyGaze method
blinking = False
# loop until there is a blink
while not blinking:
# get newest sample
gazepos = self.sample()
# check if it's a valid sample
if not self.is_valid_sample(gazepos):
# get timestamp for possible blink start
t0 = clock.get_time()
# loop until a blink is determined, or a valid sample occurs
while not self.is_valid_sample(self.sample()):
# check if time has surpassed 150 ms
if clock.get_time()-t0 >= 150:
# return timestamp of blink start
return t0
def wait_for_fixation_end(self):
"""Returns time and gaze position when a fixation has ended;
function assumes that a 'fixation' has ended when a deviation of
more than self.pxfixtresh from the initial fixation position has
been detected (self.pxfixtresh is created in self.calibration,
based on self.fixtresh, a property defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
moving = True
while moving:
# get newest event
res = 0
while res != 1:
res = iViewXAPI.iV_GetEvent(byref(eventData))
stime = clock.get_time()
# check if event is a fixation (SMI only supports
# fixations at the moment)
if eventData.eventType == 'F':
# get timestamp and starting position
timediff = stime - (int(eventData.startTime) / 1000.0)
etime = timediff + (int(eventData.endTime) / 1000.0) # time is in microseconds
fixpos = (evenData.positionX, evenData.positionY)
# return starting time and position
return etime, fixpos
# # # # #
# PyGaze method
else:
# function assumes that a 'fixation' has ended when a deviation of more than fixtresh
# from the initial 'fixation' position has been detected
# get starting time and position
stime, spos = self.wait_for_fixation_start()
# loop until fixation has ended
while True:
# get new sample
npos = self.sample() # get newest sample
# check if sample is valid
if self.is_valid_sample(npos):
# check if sample deviates to much from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# break loop if deviation is too high
break
return clock.get_time(), spos
def wait_for_fixation_start(self):
"""Returns starting time and position when a fixation is started;
function assumes a 'fixation' has started when gaze position
remains reasonably stable (i.e. when most deviant samples are
within self.pxfixtresh) for five samples in a row (self.pxfixtresh
is created in self.calibration, based on self.fixtresh, a property
defined in self.__init__)
arguments
None
returns
time, gazepos -- time is the starting time in milliseconds (from
expstart), gazepos is a (x,y) gaze position
tuple of the position from which the fixation
was initiated
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a fixation start
# detection built into their API (only ending)
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer fixation START detection (only \
fixation ENDING; PyGaze algorithm will be used")
# # # # #
# PyGaze method
# function assumes a 'fixation' has started when gaze position
# remains reasonably stable for self.fixtimetresh
# get starting position
spos = self.sample()
while not self.is_valid_sample(spos):
spos = self.sample()
# get starting time
t0 = clock.get_time()
# wait for reasonably stable position
moving = True
while moving:
# get new sample
npos = self.sample()
# check if sample is valid
if self.is_valid_sample(npos):
# check if new sample is too far from starting position
if (npos[0]-spos[0])**2 + (npos[1]-spos[1])**2 > self.pxfixtresh**2: # Pythagoras
# if not, reset starting position and time
spos = copy.copy(npos)
t0 = clock.get_time()
# if new sample is close to starting sample
else:
# get timestamp
t1 = clock.get_time()
# check if fixation time threshold has been surpassed
if t1 - t0 >= self.fixtimetresh:
# return time and starting position
return t1, spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a saccade is
ended; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos, endpos -- endtime in milliseconds (from
expbegintime); startpos and endpos
are (x,y) gaze position tuples
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
t0, spos = self.wait_for_saccade_start()
# get valid sample
prevpos = self.sample()
while not self.is_valid_sample(prevpos):
prevpos = self.sample()
# get starting time, intersample distance, and velocity
t1 = clock.get_time()
s = ((prevpos[0]-spos[0])**2 + (prevpos[1]-spos[1])**2)**0.5 # = intersample distance = speed in px/sample
v0 = s / (t1-t0)
# run until velocity and acceleration go below threshold
saccadic = True
while saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# calculate distance
s = ((newpos[0]-prevpos[0])**2 + (newpos[1]-prevpos[1])**2)**0.5 # = speed in pixels/sample
# calculate velocity
v1 = s / (t1-t0)
# calculate acceleration
a = (v1-v0) / (t1-t0) # acceleration in pixels/sample**2 (actually is v1-v0 / t1-t0; but t1-t0 = 1 sample)
# check if velocity and acceleration are below threshold
if v1 < self.pxspdtresh and (a > -1*self.pxacctresh and a < 0):
saccadic = False
epos = newpos[:]
etime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return etime, spos, epos
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a saccade is
started; based on Dalmaijer et al. (2013) online saccade detection
algorithm
arguments
None
returns
endtime, startpos -- endtime in milliseconds (from expbegintime);
startpos is an (x,y) gaze position tuple
"""
# # # # #
# SMI method
if self.eventdetection == 'native':
# print warning, since SMI does not have a blink detection
# built into their API
print("WARNING! 'native' event detection has been selected, \
but SMI does not offer saccade detection; PyGaze \
algorithm will be used")
# # # # #
# PyGaze method
# get starting position (no blinks)
newpos = self.sample()
while not self.is_valid_sample(newpos):
newpos = self.sample()
# get starting time, position, intersampledistance, and velocity
t0 = clock.get_time()
prevpos = newpos[:]
s = 0
v0 = 0
# get samples
saccadic = False
while not saccadic:
# get new sample
newpos = self.sample()
t1 = clock.get_time()
if self.is_valid_sample(newpos) and newpos != prevpos:
# check if distance is larger than precision error
sx = newpos[0]-prevpos[0]; sy = newpos[1]-prevpos[1]
if (sx/self.pxdsttresh[0])**2 + (sy/self.pxdsttresh[1])**2 > self.weightdist: # weigthed distance: (sx/tx)**2 + (sy/ty)**2 > 1 means movement larger than RMS noise
# calculate distance
s = ((sx)**2 + (sy)**2)**0.5 # intersampledistance = speed in pixels/ms
# calculate velocity
v1 = s / (t1-t0)
# calculate acceleration
a = (v1-v0) / (t1-t0) # acceleration in pixels/ms**2
# check if either velocity or acceleration are above threshold values
if v1 > self.pxspdtresh or a > self.pxacctresh:
saccadic = True
spos = prevpos[:]
stime = clock.get_time()
# update previous values
t0 = copy.copy(t1)
v0 = copy.copy(v1)
# udate previous sample
prevpos = newpos[:]
return stime, spos
def is_valid_sample(self, gazepos):
"""Checks if the sample provided is valid, based on SMI specific
criteria (for internal use)
arguments
gazepos -- a (x,y) gaze position tuple, as returned by
self.sample()
returns
valid -- a Boolean: True on a valid sample, False on
an invalid sample
"""
# return False if a sample is invalid
if gazepos == (-1,-1):
return False
# sometimes, on SMI devices, invalid samples can actually contain
# numbers; these do
elif sum(gazepos) < 10 and 0.0 in gazepos:
return False
# in any other case, the sample is valid
return True
def __init__(self,
display,
ip='127.0.0.1',
sendport=4444,
receiveport=5555,
logfile=settings.LOGFILE,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
**args):
"""Initializes the SMItracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
ip -- internal ip address for iViewX (default =
'127.0.0.1')
sendport -- port number for iViewX sending (default = 4444)
receiveport -- port number for iViewX receiving (default = 5555)
logfile -- logfile name (string value); note that this is the
name for the SMI logfile, NOT the .idf file
(default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, SMITracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = settings.DISPSIZE # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# output file properties
self.outputfile = logfile
self.description = "experiment" # TODO: EXPERIMENT NAME
self.participant = "participant" # TODO: PP NAME
# eye tracker properties
self.connected = False
self.recording = False
self.eye_used = 0 # 0=left, 1=right, 2=binocular
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.errdist = 2 # degrees; maximal error for drift correction
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# set logger
res = iViewXAPI.iV_SetLogger(c_int(1),
c_char_p(logfile + '_SMILOG.txt'))
if res != 1:
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.__init__: failed to set logger; %s"
% err)
# first logger argument is for logging type (I'm guessing these are decimal bit codes)
# LOG status bitcode
# 1 = LOG_LEVEL_BUG 00001
# 2 = LOG_LEVEL_iV_FCT 00010
# 4 = LOG_LEVEL_ETCOM 00100
# 8 = LOG_LEVEL_ALL 01000
# 16 = LOG_LEVEL_IV_COMMAND 10000
# these can be used together, using a bitwise or, e.g.: 1|2|4 (bitcode 00111)
# connect to iViewX
res = iViewXAPI.iV_Connect(c_char_p(ip), c_int(sendport), c_char_p(ip),
c_int(receiveport))
if res == 1:
res = iViewXAPI.iV_GetSystemInfo(byref(systemData))
self.samplerate = systemData.samplerate
self.sampletime = 1000.0 / self.samplerate
if res != 1:
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.__init__: failed to get system information; %s"
% err)
# handle connection errors
else:
self.connected = False
err = errorstring(res)
raise Exception(
"Error in libsmi.SMItracker.__init__: establishing connection failed; %s"
% err)
# initiation report
self.log("pygaze initiation report start")
self.log("experiment: %s" % self.description)
self.log("participant: %s" % self.participant)
self.log("display resolution: %sx%s" %
(self.dispsize[0], self.dispsize[1]))
self.log("display size in cm: %sx%s" %
(self.screensize[0], self.screensize[1]))
self.log("samplerate: %s Hz" % self.samplerate)
self.log("sampletime: %s ms" % self.sampletime)
self.log("fixation threshold: %s degrees" % self.fixtresh)
self.log("speed threshold: %s degrees/second" % self.spdtresh)
self.log("acceleration threshold: %s degrees/second**2" %
self.accthresh)
self.log("pygaze initiation report end")
def __init__(self, display, ip='127.0.0.1', sendport=4444, receiveport= \
5555, logfile=LOGFILE, eventdetection=EVENTDETECTION, \
saccade_velocity_threshold=35, saccade_acceleration_threshold=9500, \
**args):
"""Initializes the SMItracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
ip -- internal ip address for iViewX (default =
'127.0.0.1')
sendport -- port number for iViewX sending (default = 4444)
receiveport -- port number for iViewX receiving (default = 5555)
logfile -- logfile name (string value); note that this is the
name for the SMI logfile, NOT the .idf file
(default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, SMITracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = DISPSIZE # display size in pixels
self.screensize = SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw',freq=100, length=100)
# output file properties
self.outputfile = logfile
self.description = "experiment" # TODO: EXPERIMENT NAME
self.participant = "participant" # TODO: PP NAME
# eye tracker properties
self.connected = False
self.recording = False
self.eye_used = 0 # 0=left, 1=right, 2=binocular
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.errdist = 2 # degrees; maximal error for drift correction
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1,-1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# set logger
res = iViewXAPI.iV_SetLogger(c_int(1), c_char_p(logfile + '_SMILOG.txt'))
if res != 1:
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.__init__: failed to set logger; %s" % err)
# first logger argument is for logging type (I'm guessing these are decimal bit codes)
# LOG status bitcode
# 1 = LOG_LEVEL_BUG 00001
# 2 = LOG_LEVEL_iV_FCT 00010
# 4 = LOG_LEVEL_ETCOM 00100
# 8 = LOG_LEVEL_ALL 01000
# 16 = LOG_LEVEL_IV_COMMAND 10000
# these can be used together, using a bitwise or, e.g.: 1|2|4 (bitcode 00111)
# connect to iViewX
res = iViewXAPI.iV_Connect(c_char_p(ip), c_int(sendport), c_char_p(ip), c_int(receiveport))
if res == 1:
res = iViewXAPI.iV_GetSystemInfo(byref(systemData))
self.samplerate = systemData.samplerate
self.sampletime = 1000.0 / self.samplerate
if res != 1:
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.__init__: failed to get system information; %s" % err)
# handle connection errors
else:
self.connected = False
err = errorstring(res)
raise Exception("Error in libsmi.SMItracker.__init__: establishing connection failed; %s" % err)
# initiation report
self.log("pygaze initiation report start")
self.log("experiment: %s" % self.description)
self.log("participant: %s" % self.participant)
self.log("display resolution: %sx%s" % (self.dispsize[0],self.dispsize[1]))
self.log("display size in cm: %sx%s" % (self.screensize[0],self.screensize[1]))
self.log("samplerate: %s Hz" % self.samplerate)
self.log("sampletime: %s ms" % self.sampletime)
self.log("fixation threshold: %s degrees" % self.fixtresh)
self.log("speed threshold: %s degrees/second" % self.spdtresh)
self.log("acceleration threshold: %s degrees/second**2" % self.accthresh)
self.log("pygaze initiation report end")
def __init__(self, display, logfile=settings.LOGFILE, \
alea_key=settings.ALEAKEY, \
animated_calibration=settings.ALEAANIMATEDCALIBRATION, \
eventdetection=settings.EVENTDETECTION, \
saccade_velocity_threshold=35, \
saccade_acceleration_threshold=9500, \
blink_threshold=settings.BLINKTHRESH, \
**args):
"""Initializes the AleaTracker object
arguments
display -- a pygaze.display.Display instance
keyword arguments
logfile -- logfile name (string value); note that this is the
name for the eye data log file (default = LOGFILE)
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, AleaTracker)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
# object properties
self.disp = display
self.screen = Screen()
self.dispsize = self.disp.dispsize # display size in pixels
self.screensize = settings.SCREENSIZE # display size in cm
self.kb = Keyboard(keylist=['space', 'escape', 'q'], timeout=1)
self.errorbeep = Sound(osc='saw', freq=100, length=100)
# show a message
self.screen.clear()
self.screen.draw_text(
text="Initialising the eye tracker, please wait...", fontsize=20)
self.disp.fill(self.screen)
self.disp.show()
# output file properties
self.outputfile = logfile + '.tsv'
# calibration properties
self.animated_calibration = animated_calibration == True
# eye tracker properties
self.connected = False
self.recording = False
self.errdist = 2 # degrees; maximal error for drift correction
self.pxerrdist = 30 # initial error in pixels
self.maxtries = 100 # number of samples obtained before giving up (for obtaining accuracy and tracker distance information, as well as starting or stopping recording)
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
self.fixtresh = 1.5 # degrees; maximal distance from fixation start (if gaze wanders beyond this, fixation has stopped)
self.fixtimetresh = 100 # milliseconds; amount of time gaze has to linger within self.fixtresh to be marked as a fixation
self.spdtresh = saccade_velocity_threshold # degrees per second; saccade velocity threshold
self.accthresh = saccade_acceleration_threshold # degrees per second**2; saccade acceleration threshold
self.blinkthresh = blink_threshold # milliseconds; blink detection threshold used in PyGaze method
self.eventdetection = eventdetection
self.set_detection_type(self.eventdetection)
self.weightdist = 10 # weighted distance, used for determining whether a movement is due to measurement error (1 is ok, higher is more conservative and will result in only larger saccades to be detected)
# connect to the tracker
self.alea = OGAleaTracker(alea_key, file_path=self.outputfile)
# get info on the sample rate
# TODO: Compute after streaming some samples?
self.samplerate = 60.0
self.sampletime = 1000.0 / self.samplerate
# initiation report
self.log("pygaze initiation report start")
self.log("display resolution: {}x{}".format( \
self.dispsize[0], self.dispsize[1]))
self.log("display size in cm: {}x{}".format( \
self.screensize[0], self.screensize[1]))
self.log("samplerate: {} Hz".format(self.samplerate))
self.log("sampletime: {} ms".format(self.sampletime))
self.log("fixation threshold: {} degrees".format(self.fixtresh))
self.log("speed threshold: {} degrees/second".format(self.spdtresh))
self.log("acceleration threshold: {} degrees/second**2".format( \
self.accthresh))
self.log("pygaze initiation report end")
class EyelinkGraphics(custom_display):
"""
Implements the EyeLink graphics that are shown on the experimental PC, such
as the camera image, and the calibration dots. This class only implements
the drawing operations, and little to no of the logic behind the set-up,
which is implemented in PyLink.
"""
def __init__(self, libeyelink, tracker):
"""
Constructor.
Arguments:
libeyelink -- A libeyelink object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.libeyelink = libeyelink
self.display = libeyelink.display
self.screen = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=0)
self.mouse = Mouse(timeout=0)
if DISPTYPE == "pygame":
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
# if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), "__eyelink__.jpg")
# drawing properties
self.xc = self.display.dispsize[0] / 2
self.yc = self.display.dispsize[1] / 2
self.extra_info = True
self.ld = 40 # line distance
self.fontsize = libeyelink.fontsize
self.title = ""
self.display_open = True
# menu
self.menuscreen = Screen(disptype=DISPTYPE, mousevisible=False)
self.menuscreen.draw_text(
text="Eyelink calibration menu",
pos=(self.xc, self.yc - 6 * self.ld),
center=True,
font="mono",
fontsize=int(2 * self.fontsize),
antialias=True,
)
self.menuscreen.draw_text(
text="%s (pygaze %s, pylink %s)" % (libeyelink.eyelink_model, pygaze.version, pylink.__version__),
pos=(self.xc, self.yc - 5 * self.ld),
center=True,
font="mono",
fontsize=int(0.8 * self.fontsize),
antialias=True,
)
self.menuscreen.draw_text(
text="Press C to calibrate",
pos=(self.xc, self.yc - 3 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press V to validate",
pos=(self.xc, self.yc - 2 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press A to auto-threshold",
pos=(self.xc, self.yc - 1 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press I to toggle extra info in camera image",
pos=(self.xc, self.yc - 0 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press Enter to show camera image",
pos=(self.xc, self.yc + 1 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="(then change between images using the arrow keys)",
pos=(self.xc, self.yc + 2 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press Escape to abort experiment",
pos=(self.xc, self.yc + 4 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press Q to exit menu",
pos=(self.xc, self.yc + 5 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
# beeps
self.__target_beep__ = Sound(osc="sine", freq=440, length=50, attack=0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc="sine", freq=880, length=200, attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc="sine", freq=220, length=200, attack=0, decay=0, soundfile=None)
# Colors
self.color = {
pylink.CR_HAIR_COLOR: pygame.Color("white"),
pylink.PUPIL_HAIR_COLOR: pygame.Color("white"),
pylink.PUPIL_BOX_COLOR: pygame.Color("green"),
pylink.SEARCH_LIMIT_BOX_COLOR: pygame.Color("red"),
pylink.MOUSE_CURSOR_COLOR: pygame.Color("red"),
"font": pygame.Color("white"),
}
# Font
pygame.font.init()
self.font = pygame.font.SysFont("Courier New", 11)
# further properties
self.state = None
self.pal = None
self.size = (0, 0)
self.set_tracker(tracker)
self.last_mouse_state = -1
self.bit64 = "64bit" in platform.architecture()
self.imagebuffer = self.new_array()
def close(self):
"""
Is called when the connection and display are shutting down.
"""
self.display_open = False
def new_array(self):
"""
Creates a new array with a system-specific format.
Returns:
An array.
"""
# On 64 bit Linux, we need to use an unsigned int data format.
# <https://www.sr-support.com/showthread.php?3215-Visual-glitch-when-/
# sending-eye-image-to-display-PC&highlight=ubuntu+pylink>
if os.name == "posix" and self.bit64:
return array.array("I")
return array.array("L")
def set_tracker(self, tracker):
"""
Connects the tracker to the graphics environment.
Arguments:
tracker -- An tracker object as returned by pylink.EyeLink().
"""
self.tracker = tracker
self.tracker_version = tracker.getTrackerVersion()
if self.tracker_version >= 3:
self.tracker.sendCommand("enable_search_limits=YES")
self.tracker.sendCommand("track_search_limits=YES")
self.tracker.sendCommand("autothreshold_click=YES")
self.tracker.sendCommand("autothreshold_repeat=YES")
self.tracker.sendCommand("enable_camera_position_detect=YES")
def setup_cal_display(self):
"""
Sets up the initial calibration display, which contains a menu with
instructions.
"""
# show instructions
self.display.fill(self.menuscreen)
self.display.show()
def exit_cal_display(self):
"""Exits calibration display."""
self.clear_cal_display()
def record_abort_hide(self):
"""TODO: What does this do?"""
pass
def clear_cal_display(self):
"""Clears the calibration display"""
self.display.fill()
self.display.show()
def erase_cal_target(self):
"""TODO: What does this do?"""
self.clear_cal_display()
def draw_cal_target(self, x, y):
"""
Draws calibration target.
Arguments:
x -- The X coordinate of the target.
y -- The Y coordinate of the target.
"""
self.play_beep(pylink.CAL_TARG_BEEP)
self.screen.clear()
self.screen.draw_fixation(fixtype="dot", pos=(x, y))
self.display.fill(screen=self.screen)
self.display.show()
def play_beep(self, beepid):
"""
Plays a sound.
Arguments:
beepid -- A number that identifies the sound.
"""
if beepid == pylink.CAL_TARG_BEEP:
# For some reason, playing the beep here doesn't work, so we have
# to play it when the calibration target is drawn.
if EYELINKCALBEEP:
self.__target_beep__.play()
elif beepid == pylink.CAL_ERR_BEEP or beepid == pylink.DC_ERR_BEEP:
# show a picture
self.screen.clear()
self.screen.draw_text(
text="calibration lost, press 'Enter' to return to menu",
pos=(self.xc, self.yc),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.display.fill(self.screen)
self.display.show()
# play beep
self.__target_beep__error__.play()
elif beepid == pylink.CAL_GOOD_BEEP:
self.screen.clear()
if self.state == "calibration":
self.screen.draw_text(
text="Calibration succesfull, press 'v' to validate",
pos=(self.xc, self.yc),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
elif self.state == "validation":
self.screen.draw_text(
text="Validation succesfull, press 'Enter' to return to menu",
pos=(self.xc, self.yc),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
else:
self.screen.draw_text(
text="Press 'Enter' to return to menu",
pos=(self.xc, self.yc),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
# show screen
self.display.fill(self.screen)
self.display.show()
# play beep
self.__target_beep__done__.play()
else: # DC_GOOD_BEEP or DC_TARG_BEEP
pass
def draw_line(self, x1, y1, x2, y2, colorindex):
"""
Unlike the function name suggests, this draws a single pixel. I.e.
the end coordinates are always exactly one pixel away from the start
coordinates.
Arguments:
x1 -- The starting x.
y1 -- The starting y.
x2 -- The end x.
y2 -- The end y.
colorIndex -- A color index.
"""
x1 = int(self.scale * x1)
y1 = int(self.scale * y1)
x2 = int(self.scale * x2)
y2 = int(self.scale * y2)
pygame.draw.line(self.cam_img, self.color[colorindex], (x1, y1), (x2, y2))
def draw_lozenge(self, x, y, w, h, colorindex):
"""
desc:
Draws a rectangle.
arguments:
x:
desc: X coordinate.
type: int
y:
desc: Y coordinate.
type: int
w:
desc: A width.
type: int
h:
desc: A height.
type: int
colorindex:
desc: A colorindex.
type: int
"""
x = int(self.scale * x)
y = int(self.scale * y)
w = int(self.scale * w)
h = int(self.scale * h)
pygame.draw.rect(self.cam_img, self.color[colorindex], (x, y, w, h), 2)
def draw_title(self):
"""
desc:
Draws title info.
"""
y = 0
for line in self.title:
surf = self.font.render(line, 0, self.color["font"])
self.cam_img.blit(surf, (1, y))
y += 12
def get_mouse_state(self):
"""
desc:
Gets the mouse position and state.
returns:
desc: A (pos, state) tuple.
type: tuple.
"""
button, pos, time = self.mouse.get_clicked()
if button == None:
button = -1
if pos == None:
pos = self.mouse.get_pos()
return pos, button
def get_input_key(self):
"""
Gets an input key.
Returns:
A list containing a single pylink key identifier.
"""
# Don't try to collect key presses when the display is no longer
# available. This is necessary, because pylink polls key presses during
# file transfer, which generally occurs after the display has been
# closed.
if not self.display_open:
return None
try:
key, time = self.kb.get_key(keylist=None, timeout="default")
except:
self.esc_pressed = True
key = "q"
if key == None:
return None
# Escape functions as a 'q' with the additional esc_pressed flag
if key == "escape":
key = "q"
self.esc_pressed = True
# Process regular keys
if key == "return":
keycode = pylink.ENTER_KEY
self.state = None
elif key == "space":
keycode = ord(" ")
elif key == "q":
keycode = pylink.ESC_KEY
self.state = None
elif key == "c":
keycode = ord("c")
self.state = "calibration"
elif key == "v":
keycode = ord("v")
self.state = "validation"
elif key == "a":
keycode = ord("a")
elif key == "i":
self.extra_info = not self.extra_info
keycode = 0
elif key == "up":
keycode = pylink.CURS_UP
elif key == "down":
keycode = pylink.CURS_DOWN
elif key == "left":
keycode = pylink.CURS_LEFT
elif key == "right":
keycode = pylink.CURS_RIGHT
else:
keycode = 0
# Convert key to PyLink keycode and return
return [pylink.KeyInput(keycode, 0)] # 0 = pygame.KMOD_NONE
def exit_image_display(self):
"""Exits the image display."""
self.clear_cal_display()
def alert_printf(self, msg):
"""
Prints alert message.
Arguments:
msg -- The message to be played.
"""
print "eyelink_graphics.alert_printf(): %s" % msg
def setup_image_display(self, width, height):
"""
Initializes the buffer that will contain the camera image.
Arguments:
width -- The width of the image.
height -- The height of the image.
"""
self.size = width, height
self.clear_cal_display()
self.last_mouse_state = -1
self.imagebuffer = self.new_array()
def image_title(self, text):
"""
Sets the current image title.
Arguments:
text -- An image title.
"""
while ": " in text:
text = text.replace(": ", ":")
self.title = text.split()
def draw_image_line(self, width, line, totlines, buff):
"""
Draws a single eye video frame, line by line.
Arguments:
width -- Width of the video.
line -- Line nr of current line.
totlines -- Total lines in video.
buff -- Frame buffer.
imagesize -- The size of the image, which is (usually?) 192x160 px.
"""
# If the buffer hasn't been filled yet, add a line.
for i in range(width):
try:
self.imagebuffer.append(self.pal[buff[i]])
except:
pass
# If the buffer is full, push it to the display.
if line == totlines:
self.scale = totlines / 320.0
self._size = int(self.scale * self.size[0]), int(self.scale * self.size[1])
# Convert the image buffer to a pygame image, save it ...
self.cam_img = pygame.image.fromstring(self.imagebuffer.tostring(), self._size, "RGBX")
if self.extra_info:
self.draw_cross_hair()
self.draw_title()
pygame.image.save(self.cam_img, self.tmp_file)
# ... and then show the image.
self.screen.clear()
self.screen.draw_image(self.tmp_file, scale=1.5 / self.scale)
self.display.fill(self.screen)
self.display.show()
# Clear the buffer for the next round!
self.imagebuffer = self.new_array()
def set_image_palette(self, r, g, b):
"""
Sets the image palette.
TODO: What this function actually does is highly mysterious. Figure it
out!
Arguments:
r -- The red channel.
g -- The green channel.
b -- The blue channel.
"""
self.imagebuffer = self.new_array()
self.clear_cal_display()
sz = len(r)
i = 0
self.pal = []
while i < sz:
rf = int(b[i])
gf = int(g[i])
bf = int(r[i])
self.pal.append((rf << 16) | (gf << 8) | (bf))
i += 1
mouse = Mouse(mousebuttonlist=None, timeout=None)
# Initialise a log.
log = Logfile()
header = ['trialnr', 'nstim', 'fixonset', 'stimonset', 'maintenanceonset', \
'probeonset', 'RT', 'response']
for i in range(max(NSTIM)):
header.extend(['stimx%d' % (i), 'stimy%d' % (i), 'stimori%d' % (i), \
'stimerror%d' % (i)])
header.extend(['E', 'X', 'T'])
for i in range(max(NSTIM)-1):
header.append('NT%d' % i)
log.write(header)
# Initialise a blank Screen for ad-hoc drawing.
scr = Screen()
# Initialise a blank Screen.
blankscr = Screen()
# Initialise a fixation Screen.
fixscr = Screen()
fixscr.draw_fixation(fixtype=FIXTYPE, diameter=FIXSIZE, pw=FIXPW)
# Initialise stimulus and probe Screens.
stimscr = {}
probescr = {}
for nstim in NSTIM:
locs = nstim * [DISPCENTRE]
oris = nstim * [0]
stimscr[nstim] = StimScreen(nstim, locs, oris, \
def __init__(self, libeyelink, tracker):
"""
Constructor.
Arguments:
libeyelink -- A libeyelink object.
tracker -- An tracker object as returned by pylink.EyeLink().
"""
pylink.EyeLinkCustomDisplay.__init__(self)
# objects
self.libeyelink = libeyelink
self.display = libeyelink.display
self.screen = Screen(disptype=DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=None, timeout=0)
self.mouse = Mouse(timeout=0)
if DISPTYPE == "pygame":
self.kb.set_timeout(timeout=0.001)
# If we are using a DISPTYPE that cannot be used directly, we have to
# save the camera image to a temporary file on each frame.
# if DISPTYPE not in ('pygame', 'psychopy'):
import tempfile
import os
self.tmp_file = os.path.join(tempfile.gettempdir(), "__eyelink__.jpg")
# drawing properties
self.xc = self.display.dispsize[0] / 2
self.yc = self.display.dispsize[1] / 2
self.extra_info = True
self.ld = 40 # line distance
self.fontsize = libeyelink.fontsize
self.title = ""
self.display_open = True
# menu
self.menuscreen = Screen(disptype=DISPTYPE, mousevisible=False)
self.menuscreen.draw_text(
text="Eyelink calibration menu",
pos=(self.xc, self.yc - 6 * self.ld),
center=True,
font="mono",
fontsize=int(2 * self.fontsize),
antialias=True,
)
self.menuscreen.draw_text(
text="%s (pygaze %s, pylink %s)" % (libeyelink.eyelink_model, pygaze.version, pylink.__version__),
pos=(self.xc, self.yc - 5 * self.ld),
center=True,
font="mono",
fontsize=int(0.8 * self.fontsize),
antialias=True,
)
self.menuscreen.draw_text(
text="Press C to calibrate",
pos=(self.xc, self.yc - 3 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press V to validate",
pos=(self.xc, self.yc - 2 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press A to auto-threshold",
pos=(self.xc, self.yc - 1 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press I to toggle extra info in camera image",
pos=(self.xc, self.yc - 0 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press Enter to show camera image",
pos=(self.xc, self.yc + 1 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="(then change between images using the arrow keys)",
pos=(self.xc, self.yc + 2 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press Escape to abort experiment",
pos=(self.xc, self.yc + 4 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
self.menuscreen.draw_text(
text="Press Q to exit menu",
pos=(self.xc, self.yc + 5 * self.ld),
center=True,
font="mono",
fontsize=self.fontsize,
antialias=True,
)
# beeps
self.__target_beep__ = Sound(osc="sine", freq=440, length=50, attack=0, decay=0, soundfile=None)
self.__target_beep__done__ = Sound(osc="sine", freq=880, length=200, attack=0, decay=0, soundfile=None)
self.__target_beep__error__ = Sound(osc="sine", freq=220, length=200, attack=0, decay=0, soundfile=None)
# Colors
self.color = {
pylink.CR_HAIR_COLOR: pygame.Color("white"),
pylink.PUPIL_HAIR_COLOR: pygame.Color("white"),
pylink.PUPIL_BOX_COLOR: pygame.Color("green"),
pylink.SEARCH_LIMIT_BOX_COLOR: pygame.Color("red"),
pylink.MOUSE_CURSOR_COLOR: pygame.Color("red"),
"font": pygame.Color("white"),
}
# Font
pygame.font.init()
self.font = pygame.font.SysFont("Courier New", 11)
# further properties
self.state = None
self.pal = None
self.size = (0, 0)
self.set_tracker(tracker)
self.last_mouse_state = -1
self.bit64 = "64bit" in platform.architecture()
self.imagebuffer = self.new_array()
def __init__(self,
display,
resolution=settings.DISPSIZE,
data_file=settings.LOGFILENAME + ".edf",
fg_color=settings.FGC,
bg_color=settings.BGC,
eventdetection=settings.EVENTDETECTION,
saccade_velocity_threshold=35,
saccade_acceleration_threshold=9500,
blink_threshold=settings.BLINKTHRESH,
force_drift_correct=True,
pupil_size_mode=settings.EYELINKPUPILSIZEMODE,
**args):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
# try to import copy docstring (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, libeyelink)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
global _eyelink
# Make sure that we have a valid data file. The local_data_file may
# contain a folder. The eyelink_data_file is only a basename, i.e.
# without folder. The eyelink_data_file must be at most eight characters
# and end with a `.edf` extension.
self.local_data_file = data_file
self.eyelink_data_file = os.path.basename(data_file)
stem, ext = os.path.splitext(self.eyelink_data_file)
if len(stem) > 8 or ext.lower() != '.edf':
raise Exception(
"The EyeLink cannot handle filenames longer than eight "
"characters (excluding '.edf' extension).")
# properties
self.display = display
self.fontsize = 18
self.scr = Screen(disptype=settings.DISPTYPE, mousevisible=False)
self.kb = Keyboard(keylist=["escape", "q"], timeout=1)
self.resolution = resolution
self.recording = False
self.saccade_velocity_treshold = saccade_velocity_threshold
self.saccade_acceleration_treshold = saccade_acceleration_threshold
self.blink_threshold = blink_threshold
self.eye_used = None
self.left_eye = 0
self.right_eye = 1
self.binocular = 2
self.pupil_size_mode = pupil_size_mode
self.prevsample = (-1, -1)
self.prevps = -1
# event detection properties
# degrees; maximal distance from fixation start (if gaze wanders beyond
# this, fixation has stopped)
self.fixtresh = 1.5
# milliseconds; amount of time gaze has to linger within self.fixtresh
# to be marked as a fixation
self.fixtimetresh = 100
# degrees per second; saccade velocity threshold
self.spdtresh = self.saccade_velocity_treshold
# degrees per second**2; saccade acceleration threshold
self.accthresh = self.saccade_acceleration_treshold
self.set_detection_type(eventdetection)
# weighted distance, used for determining whether a movement is due to
# measurement error (1 is ok, higher is more conservative and will
# result in only larger saccades to be detected)
self.weightdist = 10
# distance between participant and screen in cm
self.screendist = settings.SCREENDIST
# distance between participant and screen in cm
self.screensize = settings.SCREENSIZE
self.pixpercm = (self.resolution[0]/float(self.screensize[0]) + \
self.resolution[1]/float(self.screensize[1])) / 2.0
# only initialize eyelink once
if _eyelink == None:
try:
_eyelink = pylink.EyeLink()
except:
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to "
"connect to the tracker!")
# determine software version of tracker
self.tracker_software_ver = 0
self.eyelink_ver = pylink.getEYELINK().getTrackerVersion()
if self.eyelink_ver == 3:
tvstr = pylink.getEYELINK().getTrackerVersionString()
vindex = tvstr.find("EYELINK CL")
self.tracker_software_ver = int(float(tvstr[(vindex + \
len("EYELINK CL")):].strip()))
if self.eyelink_ver == 1:
self.eyelink_model = 'EyeLink I'
elif self.eyelink_ver == 2:
self.eyelink_model = 'EyeLink II'
elif self.eyelink_ver == 3:
self.eyelink_model = 'EyeLink 1000'
else:
self.eyelink_model = 'EyeLink (model unknown)'
# Open graphics
self.eyelink_graphics = EyelinkGraphics(self, _eyelink)
pylink.openGraphicsEx(self.eyelink_graphics)
# Optionally force drift correction. For some reason this must be done
# as (one of) the first things, otherwise a segmentation fault occurs.
if force_drift_correct:
try:
self.send_command('driftcorrect_cr_disable = OFF')
except:
print('Failed to force drift correction (EyeLink 1000 only)')
# Set pupil-size mode
if self.pupil_size_mode == 'area':
pylink.getEYELINK().setPupilSizeDiameter(False)
elif self.pupil_size_mode == 'diameter':
pylink.getEYELINK().setPupilSizeDiameter(True)
else:
raise Exception(
"pupil_size_mode should be 'area' or 'diameter', not %s" \
% self.pupil_size_mode)
pylink.getEYELINK().openDataFile(self.eyelink_data_file)
pylink.flushGetkeyQueue()
pylink.getEYELINK().setOfflineMode()
# notify eyelink of display resolution
self.send_command("screen_pixel_coords = 0 0 %d %d" % \
(self.resolution[0], self.resolution[1]))
# get some configuration stuff
if self.eyelink_ver >= 2:
self.send_command("select_parser_configuration 0")
if self.eyelink_ver == 2: # turn off scenelink camera stuff
self.send_command("scene_camera_gazemap = NO")
# set EDF file contents (this specifies which data is written to the EDF
# file)
self.send_command(
"file_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,MESSAGE,BUTTON"
)
if self.tracker_software_ver >= 4:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS,HTARGET"
)
else:
self.send_command(
"file_sample_data = LEFT,RIGHT,GAZE,AREA,GAZERES,STATUS")
# set link data (this specifies which data is sent through the link and
# thus can be used in gaze contingent displays)
self.send_command(
"link_event_filter = LEFT,RIGHT,FIXATION,SACCADE,BLINK,BUTTON")
if self.tracker_software_ver >= 4:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS,HTARGET"
)
else:
self.send_command(
"link_sample_data = LEFT,RIGHT,GAZE,GAZERES,AREA,STATUS")
# not quite sure what this means (according to Sebastiaan Mathot, it
# might be the button that is used to end drift correction?)
self.send_command("button_function 5 'accept_target_fixation'")
if not self.connected():
raise Exception(
"Error in libeyelink.libeyelink.__init__(): Failed to connect "
"to the eyetracker!")
class Dummy(DumbDummy):
"""A dummy class to run experiments in dummy mode, where eye movements are simulated by the mouse"""
def __init__(self, display):
"""Initiates an eyetracker dummy object, that simulates gaze position using the mouse
arguments
display -- a pygaze display.Display instance
keyword arguments
None
"""
# try to copy docstrings (but ignore it if it fails, as we do
# not need it for actual functioning of the code)
try:
copy_docstr(BaseEyeTracker, Dummy)
except:
# we're not even going to show a warning, since the copied
# docstring is useful for code editors; these load the docs
# in a non-verbose manner, so warning messages would be lost
pass
self.recording = False
self.blinking = False
self.bbpos = (settings.DISPSIZE[0]/2, settings.DISPSIZE[1]/2)
self.resolution = settings.DISPSIZE[:]
self.simulator = Mouse(disptype=settings.DISPTYPE, mousebuttonlist=None,
timeout=2, visible=False)
self.kb = Keyboard(disptype=settings.DISPTYPE, keylist=None,
timeout=None)
self.angrybeep = Sound(osc='saw',freq=100, length=100, attack=0,
decay=0, soundfile=None)
self.display = display
self.screen = Screen(disptype=settings.DISPTYPE, mousevisible=False)
def calibrate(self):
"""Dummy calibration"""
print("Calibration would now take place")
clock.pause(1000)
def drift_correction(self, pos=None, fix_triggered=False):
"""Dummy drift correction"""
print("Drift correction would now take place")
if fix_triggered:
return self.fix_triggered_drift_correction(pos)
if pos == None:
pos = settings.DISPSIZE[0] / 2, settings.DISPSIZE[1] / 2
# show mouse
self.simulator.set_visible(visible=True)
# show fixation dot
self.draw_drift_correction_target(pos[0], pos[1])
# perform drift check
errdist = 60 # pixels (on a 1024x768px and 39.9x29.9cm monitor at 67 cm, this is about 2 degrees of visual angle)
pressed = None
while True:
# check for keyboard input
pressed, presstime = self.kb.get_key(keylist=['q','escape','space'], timeout=1)
# quit key
if pressed in ['q','escape']:
# hide mouse
self.simulator.set_visible(visible=False)
return False
# space bar
elif pressed == 'space':
# get sample
gazepos = self.sample()
# sample is close enough to fixation dot
if ((gazepos[0]-pos[0])**2 + (gazepos[1]-pos[1])**2)**0.5 < errdist:
# hide mouse
self.simulator.set_visible(visible=False)
return True
# sample is NOT close enough to fixation dot
else:
# show discontent
self.angrybeep.play()
def fix_triggered_drift_correction(self, pos=None, min_samples=30, max_dev=60, reset_threshold=10):
"""Dummy drift correction (fixation triggered)"""
print("Drift correction (fixation triggered) would now take place")
if pos == None:
pos = settings.DISPSIZE[0] / 2, settings.DISPSIZE[1] / 2
# show mouse
self.simulator.set_visible(visible=True)
# show fixation dot
self.draw_drift_correction_target(pos[0], pos[1])
while True:
# loop until we have sufficient samples
lx = []
ly = []
while len(lx) < min_samples:
# pressing escape enters the calibration screen
if self.kb.get_key(keylist=["escape", "q"], timeout=0)[0] != None:
self.recording = False
print("libeyetracker.libeyetracker.fix_triggered_drift_correction(): 'q' pressed")
self.simulator.set_visible(visible=False)
return False
# collect a sample
x, y = self.sample()
if len(lx) == 0 or x != lx[-1] or y != ly[-1]:
# if present sample deviates too much from previous sample, reset counting
if len(lx) > 0 and (abs(x - lx[-1]) > reset_threshold or abs(y - ly[-1]) > reset_threshold):
lx = []
ly = []
# collect samples
else:
lx.append(x)
ly.append(y)
# check if samples are within max. deviation
if len(lx) == min_samples:
avg_x = sum(lx) / len(lx)
avg_y = sum(ly) / len(ly)
d = ((avg_x - pos[0]) ** 2 + (avg_y - pos[1]) ** 2)**0.5
if d < max_dev:
self.simulator.set_visible(visible=False)
return True
else:
lx = []
ly = []
def start_recording(self):
"""Dummy for starting recording, prints what would have been the recording start"""
self.simulator.set_visible(visible=True)
dumrectime = clock.get_time()
self.recording = True
print("Recording would have started at: " + str(dumrectime))
def stop_recording(self):
"""Dummy for stopping recording, prints what would have been the recording end"""
self.simulator.set_visible(visible=False)
dumrectime = clock.get_time()
self.recording = False
print("Recording would have stopped at: " + str(dumrectime))
def close(self):
"""Dummy for closing connection with eyetracker, prints what would have been connection closing time"""
if self.recording:
self.stop_recording()
closetime = clock.get_time()
print("eyetracker connection would have closed at: " + str(closetime))
def pupil_size(self):
"""Returns dummy pupil size"""
return 19
def sample(self):
"""Returns simulated gaze position (=mouse position)"""
if self.blinking:
if self.simulator.get_pressed()[2]: # buttondown
self.simulator.set_pos(pos=(self.bbpos[0],self.resolution[1])) # set position to blinking position
elif not self.simulator.get_pressed()[2]: # buttonup
self.simulator.set_pos(pos=self.bbpos) # set position to position before blinking
self.blinking = False # 'blink' stopped
elif not self.blinking:
if self.simulator.get_pressed()[2]: # buttondown
self.blinking = True # 'blink' started
self.bbpos = self.simulator.get_pos() # position before blinking
self.simulator.set_pos(pos=(self.bbpos[0],self.resolution[1])) # set position to blinking position
return self.simulator.get_pos()
def wait_for_saccade_start(self):
"""Returns starting time and starting position when a simulated saccade is started"""
# function assumes that a 'saccade' has been started when a deviation of more than
# maxerr from the initial 'gaze' position has been detected (using Pythagoras, ofcourse)
spos = self.sample() # starting position
maxerr = 3 # pixels
while True:
npos = self.sample() # get newest sample
if ((spos[0]-npos[0])**2 + (spos[1]-npos[1])**2)**0.5 > maxerr: # Pythagoras
break
return clock.get_time(), spos
def wait_for_saccade_end(self):
"""Returns ending time, starting and end position when a simulated saccade is ended"""
# function assumes that a 'saccade' has ended when 'gaze' position remains reasonably
# (i.e.: within maxerr) stable for five samples
# for saccade start algorithm, see wait_for_fixation_start
stime, spos = self.wait_for_saccade_start()
maxerr = 3 # pixels
# wait for reasonably stable position
xl = [] # list for last five samples (x coordinate)
yl = [] # list for last five samples (y coordinate)
moving = True
while moving:
# check positions
npos = self.sample()
xl.append(npos[0]) # add newest sample
yl.append(npos[1]) # add newest sample
if len(xl) == 5:
# check if deviation is small enough
if max(xl)-min(xl) < maxerr and max(yl)-min(yl) < maxerr:
moving = False
# remove oldest sample
xl.pop(0); yl.pop(0)
# wait for a bit, to avoid immediately returning (runs go faster than mouse moves)
clock.pause(10)
return clock.get_time(), spos, (xl[len(xl)-1],yl[len(yl)-1])
def wait_for_fixation_start(self):
"""Returns starting time and position when a simulated fixation is started"""
# function assumes a 'fixation' has started when 'gaze' position remains reasonably
# stable for five samples in a row (same as saccade end)
maxerr = 3 # pixels
# wait for reasonably stable position
xl = [] # list for last five samples (x coordinate)
yl = [] # list for last five samples (y coordinate)
moving = True
while moving:
npos = self.sample()
xl.append(npos[0]) # add newest sample
yl.append(npos[1]) # add newest sample
if len(xl) == 5:
# check if deviation is small enough
if max(xl)-min(xl) < maxerr and max(yl)-min(yl) < maxerr:
moving = False
# remove oldest sample
xl.pop(0); yl.pop(0)
# wait for a bit, to avoid immediately returning (runs go faster than mouse moves)
clock.pause(10)
return clock.get_time(), (xl[len(xl)-1],yl[len(yl)-1])
def wait_for_fixation_end(self):
"""Returns time and gaze position when a simulated fixation is ended"""
# function assumes that a 'fixation' has ended when a deviation of more than maxerr
# from the initial 'fixation' position has been detected (using Pythagoras, ofcourse)
stime, spos = self.wait_for_fixation_start()
maxerr = 3 # pixels
while True:
npos = self.sample() # get newest sample
if ((spos[0]-npos[0])**2 + (spos[1]-npos[1])**2)**0.5 > maxerr: # Pythagoras
break
return clock.get_time(), spos
def wait_for_blink_start(self):
"""Returns starting time and position of a simulated blink (mousebuttondown)"""
# blinks are simulated with mouseclicks: a right mouseclick simulates the closing
# of the eyes, a mousebuttonup the opening.
while not self.blinking:
pos = self.sample()
return clock.get_time(), pos
def wait_for_blink_end(self):
"""Returns ending time and position of a simulated blink (mousebuttonup)"""
# blinks are simulated with mouseclicks: a right mouseclick simulates the closing
# of the eyes, a mousebuttonup the opening.
# wait for blink start
while not self.blinking:
spos = self.sample()
# wait for blink end
while self.blinking:
epos = self.sample()
return clock.get_time(), epos
def set_draw_drift_correction_target_func(self, func):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
self.draw_drift_correction_target = func
# ***
#
# Internal functions below
#
# ***
def draw_drift_correction_target(self, x, y):
"""
Draws the drift-correction target.
arguments
x -- The X coordinate
y -- The Y coordinate
"""
self.screen.clear()
self.screen.draw_fixation(fixtype='dot', colour=settings.FGC, \
pos=(x,y), pw=0, diameter=12)
self.display.fill(self.screen)
self.display.show()
