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ffmpegkeyframe

ffmpeg extract single keyframe to image and get timestamp of keyframe

After searching for frames in a video that match an image, getting the following output

[Parsed_blackframe_1 @ 0x55a8513722c0] frame:884 pblack:99 pts:452608 t:35.360000 type:B last_keyframe:864

How to extract an image of a the last_keyframe in the case above 864?

How to get the timestamp of the last_keyframe in the case above 864?

Solution

  • How to extract an image of a the last_keyframe in the case above 864?

    ffmpeg -i input -vf select=eq(pict_type\,I)*gt(n\,864) -update 1 -vsync 0 last.png
    • select filter keeps only the key(I) frames and(*) frames above #864
    • -update 1 discards/overwrites the previous frame, so the final frame is saved
    • -vsync 0 keeps encoder from unnecessarily making copies of the key frames to fill the time

    How to get the timestamp of the last_keyframe in the case above 864?

    I don't know if there is a way to do this in FFmpeg, but with FFprobe you can run the following to get all the keyframe timestamps:

    ffprobe -skip_frame nokey -select_streams v:0 -show_entries frame=pts_time

    References: