Vapoursynth Frames and Keyframes

[jay123210599]

Whenever I put a video in a vapoursynth script, all the frames become keyframes. How do I keep the default frames and keyframes from the original videos in scripts?

[poisondeathray]

Originally Posted by jay123210599

Whenever I put a video in a vapoursynth script, all the frames become keyframes. How do I keep the default frames and keyframes from the original videos in scripts?

You can't , because video is decoded to uncompressed data when you use scripts

[_Al_]

you can check clip frame properties if original frame was I, P or B, if source plugin read those:

n=234
frame_type = clip.get_frame(n).props.get("_PictType")
if frame_type is not None:
    print(f'frame number: {n},  frame type: {frame_type.decode("utf-8")}')

>>>frame number: 234, frame type: I

[Selur]

How do I keep the default frames and keyframes from the original videos in scripts?

The distinction between the frames is just a 'flag' after decoding.
ClipInfo might be interesting too.
Something like

src = core.bs.VideoSource(source="G:/TestClips&Co/files/test.avi")

def show_frame_type(n, f):
    # read the pict type prop, handling both bytes and str
    frame_type = f.props.get("_PictType")
    if isinstance(frame_type, bytes):
        frame_type = frame_type.decode("utf-8")
    if frame_type is None:
        frame_type = "unknown"

    txt = f"Frame: {n} | Type: {frame_type}"
    return core.text.Text(src, text=txt)

# FrameEval expects you to return a clip; prop_src gives you 'f' in the callback
clip = core.std.FrameEval(src, eval=show_frame_type, prop_src=src)

works fine. Important: 'clip = core.std.FrameEval(src, eval=show_frame_type, prop_src=src)' input and output need to be different variables.

Cu Selur