Fixed exception not rethrown in webcamvideostream

Fixed FATAL: exception not rethrown in webcamvideostream PyImageSearch#237

imutils/video/webcamvideostream.py

@@ -11,16 +11,19 @@ def __init__(self, src=0, name="WebcamVideoStream"):
 
 		# initialize the thread name
 		self.name = name
+
+		# create a thread 
+		self.thread = None
 
 		# initialize the variable used to indicate if the thread should
 		# be stopped
 		self.stopped = False
 
 	def start(self):
 		# start the thread to read frames from the video stream
-		t = Thread(target=self.update, name=self.name, args=())
-		t.daemon = True
-		t.start()
+		self.thread = Thread(target=self.update, name=self.name, args=())
+		self.thread.daemon = True
+		self.thread.start()
 		return self
 
 	def update(self):
@@ -40,3 +43,7 @@ def read(self):
 	def stop(self):
 		# indicate that the thread should be stopped
 		self.stopped = True
+		# wait until stream resources are released (producer thread might be still grabbing frame)
+		if self.thread is not None:
+			self.thread.join()
+			# properly handle stop the thread