def __init__(self, video_path, world):
self.world = world
self.capture = cv2.VideoCapture(video_path)
self.lc = LogController(world)
self.fgbs = cv2.BackgroundSubtractorMOG2(history=1000,
varThreshold = 500,
bShadowDetection = False)
self.detector = self._buildBlobDetector()
class VideoController:
"""
A class for managing a traffic camera feed.
Initializing will create itself a log file
Provides the function runInfinite that can
cycle through the frames of a stationary traffic
camera feed and write the average number of cars
detected over the Time Interval once at the end
of every interval
"""
def __init__(self, video_path, world):
self.world = world
self.capture = cv2.VideoCapture(video_path)
self.lc = LogController(world)
self.fgbs = cv2.BackgroundSubtractorMOG2(history=1000,
varThreshold = 500,
bShadowDetection = False)
self.detector = self._buildBlobDetector()
def runInfinite(self,tkroot=None):
"""
Runs the video in sets of intervals computing and logging averages
after TIME_INTERVAL seconds.
"""
while(True):
try:
averages = self._runInterval()
timestamp = datetime.datetime.now().strftime("%Y/%m/%d %H:%M:%S")
if not settings.DEBUG:
self.lc.writeToLog(timestamp,averages)
#===============================================================
# if tkroot is not None:
# tkroot.addLog(packet)
# #retrieve pause signal from button press in tk
# # will only be caught after Time interval elapses
# play = tkroot.runUpdate()
# if not(play):
# break
#===============================================================
except:
break
def _runInterval(self):
"""
A gui function that runs a TIME_INTERVAL interval
and returns a dictionary using the same keys as
the command args in --world to provide the average
count of traffic detected moving in the world directions
"""
frames_run = 0
#reinitialize the traffic counts
averages = {}
for k in self.world.keys():
averages[k] = 0
previous_keypoints = None
timeout = time.time() + TIME_INTERVAL
while time.time() < timeout:
iterDict = self._runIteration(previous_keypoints)
previous_keypoints = iterDict['keypoints']
averages_dict = iterDict['averages']
frames_run += 1
for k,v in averages_dict.iteritems():
averages[k] += v
#compute average over interval
for k in self.world.keys():
averages[k] = math.ceil(averages[k] / float(frames_run))
return averages
def _runIteration(self, previous_keypoints, return_frame=False):
"""
The function of the controller that processes
the next frame of the video and calculates the number
of vehicles. It only processes a single image and therefore
must be called inside a loop like runinterval
The flag return_frame can turned on to return the frame
with the detected vehicles and a summary count drawn
"""
frame = self._getFrame()
keypoints, averages = frame.analyzeFrame(previous_keypoints, self.world)
return {'keypoints':keypoints, 'averages':averages}
def _getFrame(self):
flag,img = self.capture.read()
if not flag:
raise Exception("Could not read video")
frame = Frame(img, self.fgbs, self.detector)
return frame
def _buildBlobDetector(self):
"""
creates a blob detector that can be used to identify the relevant
blobs of a background subtracted image. Algorithm can be improved
by supplying a truly empty frame to better remove noise.
"""
params = cv2.SimpleBlobDetector_Params()
params.filterByColor = True
params.blobColor = 255
params.filterByConvexity = True
params.minConvexity = 0.87
return cv2.SimpleBlobDetector(params)
def stopVideo(self):
self.capture.release()
