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!")
