def _init_cam(self):
"""
Initialises the CvPiCamera object to provide the frames
"""
self._cam = CvPiCamera()
self._cam.resolution = FRAME_SIZE[::-1] # openCV flips dimensions
if os.getuid() == 0:
self._cam.led = False
else:
print("LED kept on. To turn off run as root")
class PiVideoStream(VideoStream):
"""
A subclass of VideoStream for the raspberryPi camera
which isn't supported by opencv
"""
def __init__(self, savePath, bgStart, nBackgroundFrames):
"""
:param str filePath: The destination file path to save the video to
:param int bgStart: The frame to use as background frames range start
:param int nBackgroundFrames: The number of frames to use for the background
"""
VideoStream.__init__(self, savePath, bgStart, nBackgroundFrames)
def _init_cam(self):
"""
Initialises the CvPiCamera object to provide the frames
"""
self._cam = CvPiCamera()
self._cam.resolution = FRAME_SIZE[::-1] # openCV flips dimensions
if os.getuid() == 0:
self._cam.led = False
else:
print("LED kept on. To turn off run as root")
def _startVideoCaptureSession(self, savePath):
"""
Initiates a picamera.array.PiRGBArray object to store
the frames from the picamera when reading
and a cv2.VideoWriter object to save a potential output
:param str filePath: the destination file path
:return: array and videoWriter object
:type: (picamera.array.PiRGBArray, cv2.VideoWriter)
"""
videoWriter = cv2.VideoWriter(savePath, CODEC, FPS, FRAME_SIZE)
stream = picamera.array.PiRGBArray(self._cam)
return stream, videoWriter
def read(self):
"""
Returns the next frame after updating the count
:return: A video frame
:rtype: video_frame.Frame
"""
stream = self.stream
self._cam.quickCapture(stream)
# stream.array now contains the image data in BGR order
frame = stream.array
stream.truncate(0)
self.currentFrameIdx +=1
return Frame(frame.astype(np.float32))
def restartRecording(self, reset):
"""
Restarts the camera and potentially resets the output stream and frame index
:param bool reset: Whether to reset the output stream (overwrite previous) and frame index
"""
if self._cam.closed:
self._init_cam()
if reset:
self.stream, self.videoWriter = self._startVideoCaptureSession(self.savePath)
self.currentFrameIdx = -1
def stopRecording(self, msg):
"""
Stops recording and performs cleanup actions
:param str msg: The message to print before closing.
"""
VideoStream.stopRecording(self, msg)
self._cam.closeEncoder()
self._cam.close()
