On Sun, Jul 12, 2020 at 6:16 AM <lance.lmw...@gmail.com> wrote: > I have add fate timecode testing for h264/hevc and haven't submit yet. But if > the frame rate > 30, I got one unexpected result after map SMPTE ST 12-1:2014 > side data to HEVC timecode, the frame is 6bit only(2bit for tens of frame), > so to framerate > 30, it'll be divided by 2 with same timecode, but HEVC > timecode > frame number can use 9bit and expect the frame > 30.
You should still divide it by 2, even though HEVC supports more bits for the frame number. This is to be consistent with SMPTE 12-1 timecode, and downstream muxers/outputs aren't going to know whether the upstream decoder was H.264 or HEVC. On the encode side, you can multiple by 2 and use the field bit to determine whether to then add 1. See SMPTE ST 12-1:2014 Sec 12.2. There's an argument that we should add support for higher framerates to support SMPTE 12-3 (which supports fps > 60), but that should be a different side data field. Right now the most important thing is that the behavior be consistent across decoders. Devin -- Devin Heitmueller, Senior Software Engineer LTN Global Communications o: +1 (301) 363-1001 w: https://ltnglobal.com e: devin.heitmuel...@ltnglobal.com _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
