helpers.py 文件源码

def read_video(v_name):
    """A workaround function for reading video.

    Apparently precompiled OpenCV couldn't read AVI videos on Mac OS X
    and Linux,
    therefore I use PyAV, a ffmpeg binding to extract video frames

    Parameters
    ----------
    v_name : string
        absolute path to video

    Returns
    -------
    frames : list
        An ordered list for storing frames
    num_frames : int
        number of frames in the video
    """
    container = av.open(v_name)
    video = next(s for s in container.streams if s.type == b'video')

    frames = []
    for packet in container.demux(video):
        for frame in packet.decode():
            frame_t = np.array(frame.to_image())
            frames.append(cv2.cvtColor(frame_t, cv2.COLOR_RGB2BGR))

    return frames, len(frames)