def setup(self):
self.detector = FaceDetector(show_cam=False)
self.present = True
class FacePresence(Thread):
def __init__(self):
self.setup()
Thread.__init__(self)
self.search_faces = False
self.face_thread = None
def setup(self):
self.detector = FaceDetector(show_cam=False)
self.present = True
def run (self):
"""Start the loop that keeps tracking the user's face."""
if self.search_faces == False:
self.search_faces = True
self.detect()
def stop(self):
self.search_faces = False
# stop the face detection thread (if running)
if self.face_thread != None:
self.face_thread.join()
self.face_thread = None
def detect(self):
# remember the number of seconds since we last detected a
# face, and assume we detected one at the start
last_time = datetime.now()
# if we don't detect anything for 1 seconds, assume user is away
away_treshold = timedelta(seconds=1)
# eliminate false positives by requiring at least 15 detections
# in a period of 5 seconds to allow the status to be changed
# to available.
fp_num = 15
fp_duration = timedelta(seconds=5)
fp_list = [last_time]
fp_list[1:] = [datetime.fromtimestamp(0)] * (fp_num - 1)
fi = 0
self.present = False
while self.search_faces:
# detect a face/body
(detected, is_face) = self.detector.fetch_and_detect()
if detected:
fi = fi + 1
last_time = datetime.now()
fp_list[fi % fp_num] = last_time
if not self.present:
# possible switch to available
if fp_list[fi % fp_num] - fp_list[0] < fp_duration:
# we detected {fp_num} faces during the last 5 seconds
#print '%s - %s < %s' % (fp_list[fp_num-1], fp_list[0], fp_duration)
self.present = True
else:
if self.present:
# possible switch to away
if datetime.now() - last_time > away_treshold:
self.present = False