av_writer.py 文件源码

def __init__(self, file_loc,fps=30):
        super().__init__()
        # the approximate capture rate.
        self.fps = int(fps)
        self.time_base = Fraction(1000,self.fps*1000)
        file_loc = str(file_loc) #force str over unicode.
        try:
            file_path,ext = file_loc.rsplit('.', 1)
        except:
            logger.error("'{}' is not a valid media file name.".format(file_loc))
            raise Exception("Error")

        if ext not in ('mp4'):
            logger.warning("media file container should be mp4. Using a different container is risky.")

        self.file_loc = file_loc
        self.container = av.open(self.file_loc,'w')
        logger.debug("Opened '{}' for writing.".format(self.file_loc))

        self.video_stream = self.container.add_stream('mjpeg',1/self.time_base)
        self.video_stream.pix_fmt = "yuvj422p"
        self.configured = False
        self.frame_count = 0

        self.write_video_frame_compressed = self.write_video_frame