why can't I access this attribute?

[dotysan]

    input_container = av.open(RTSP_URL)
    video_stream: av.VideoStream = input_container.streams.video[0]
    print(video_stream)
    print(video_stream.gop_size)

<av.VideoStream #1 h264, yuv420p 1280x720 at 0x7ff308dc4a00>
Traceback (most recent call last):
  File "test.py", line 28, in main
    print(video_stream.gop_size)
          ^^^^^^^^^^^^^^^^^^^^^
  File "av/video/stream.pyx", line 21, in av.video.stream.VideoStream.__getattr__
  File "av/video/codeccontext.pyx", line 160, in av.video.codeccontext.VideoCodecContext.gop_size.__get__
RuntimeError: Cannnot access 'gop_size' as a decoder

Shouldn't it be a simple int?

PyAV/av/video/stream.pyi

Line 33 in ee30e4f

gop_size: int

[WyattBlue]

Because the gop_size value for a decoder would, at best, produce a nonsense answer, and at worst, be slightly wrong or coincidentally correct.

gop_size tells the encoder how many non-keyframes there should be between each keyframe. Of course, the encoder might use that as only a rough guideline or ignore it completely. If you want to know the "gop_size" for a decoder. You can decode the frames in a loop, then check frame.is_keyframe to calculate the value.

[dotysan]

Thank you!