added coded_picture_number property to VideoFrame

[mastak]

Added information about picture number in bitstream order. Some times frames can be in broken order, for example 1, 2, 3...12, 14, 13, 15, 16.... And coded_picture_number possible way to detect it.

[mikeboers]

Thanks for this.

Looking at the FFmpeg code though, I can't find where this is actually set except in h.264. Do you know how reliable this is globally?

[mikeboers]

Looking at these:

$ grep -IR --include '*.c' coded_picture_number vendor/ffmpeg-4.2
vendor/ffmpeg-4.2/libavutil/frame.c:    dst->coded_picture_number   = src->coded_picture_number;
vendor/ffmpeg-4.2/fftools/ffprobe.c:        print_int("coded_picture_number",   frame->coded_picture_number);
vendor/ffmpeg-4.2/libavcodec/ratecontrol.c:             s->current_picture_ptr->f->coded_picture_number,
vendor/ffmpeg-4.2/libavcodec/mpegvideo.c:    s->coded_picture_number = s1->coded_picture_number;
vendor/ffmpeg-4.2/libavcodec/mpegvideo.c:    s->coded_picture_number  = 0;
vendor/ffmpeg-4.2/libavcodec/mpegvideo.c:    pic->f->coded_picture_number = s->coded_picture_number++;
vendor/ffmpeg-4.2/libavcodec/h264_slice.c:    h->coded_picture_number = h1->coded_picture_number;
vendor/ffmpeg-4.2/libavcodec/h264_slice.c:    pic->f->coded_picture_number = h->coded_picture_number++;
vendor/ffmpeg-4.2/libavcodec/snowenc.c:    s->current_picture->coded_picture_number = avctx->frame_number;
vendor/ffmpeg-4.2/libavcodec/snowenc.c:    s->m.current_picture.f->coded_picture_number   = avctx->frame_number;
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:            s->reordered_input_picture[0]->f->coded_picture_number =
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:                s->coded_picture_number++;
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:            s->reordered_input_picture[0]->f->coded_picture_number =
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:                s->coded_picture_number++;
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:                s->reordered_input_picture[i + 1]->f->coded_picture_number =
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:                    s->coded_picture_number++;
vendor/ffmpeg-4.2/libavcodec/mpegvideo_enc.c:            if (!s->current_picture.f->coded_picture_number)
vendor/ffmpeg-4.2/libavcodec/mpeg12enc.c:        time_code = s->current_picture_ptr->f->coded_picture_number +
vendor/ffmpeg-4.2/libavcodec/mpeg12enc.c:        s->gop_picture_number = s->current_picture_ptr->f->coded_picture_number;
vendor/ffmpeg-4.2/doc/examples/demuxing_decoding.c:                   video_frame_count++, frame->coded_picture_number);

It only looks like h.264 and mpeg set it while decoding.

[mastak]

In the case with dvd (.vob) format it also has information.

As for webm - it always contains 0 (zeros).

[mikeboers]

Those are container formats, and it is the codec that sets that attribute. DVDs are MPEG2 IIRC, so that makes sense.

[mastak]

I don't have much knowledge in this domain area. If you would describe specific cases for verification, I can check, and if necessary, add tests.

[mastak]

@mikeboers How about those updates? Is there a chance for this PR?

[jlaine]

This needs unit tests.

[WyattBlue]

This PR is so basic, and nothing has happened for so long. I don't think it's worth keeping it open anymore.

[ValeZAA]

@WyattBlue please note that code is wrong anyway as the underlying stuff got deprecated. https://github.com/FFmpeg/FFmpeg/commit/22960783978d9e0b6d4a4ed21f503bd24662aa7e