On Thu, May 22, 2025 at 4:35 PM Gabriel Hege <g+ffm...@hege.cc> wrote:
> > On 17.05.25 04:26, Nuo Mi wrote: > > On Fri, May 16, 2025 at 7:05 PM Gabriel Hege <g+ffm...@hege.cc> wrote: > > > >> This is a resubmission with a corrected commit message. > >> > >> > >> The default behavior for VVenC (since v1.10.0) is to create an IDR with > >> leading pictures for the first picture in decoding order (POC 32). This > >> leads to FFmpeg generating an edit list with an empty entry, skipping > >> the leading pictures. > >> > >> This patch fixes the calculation for the start_pts, while the DTS is > >> negative (as produced by libvvenc). > >> > >> > >> How to reproduce the issue (needs --enable-libvvenc and a recent > >> libvvenc, e.g. v1.13): > >> > > Hi Gabriel, > > Thank you for your patch. It addresses the MP4 issue, but it looks like > MKV > > has the same problem as well. > > Hi Nuo Mi, > > I'm sorry I don't really have an understanding of the MKV format. I had > a quick look at the code, but the processing seems quite different and I > didn't really find the corresponding code locations to fix the problem > there. > Hi Gabriel, Thank you for checking. Could you help create a similar issue for MKV? Someone familiar with MKV might pick it up. Hi James and all, If no one objects, I’ll push this. Thank you. > > > > Hi @James Almer <jamr...@gmail.com> , > > Could you please take a look at the patch when you have a moment? You've > > been the most active contributor to this file recently. > > > >> > >> Encode VVC directly into MP4 container: > >> ./ffmpeg -i /data/YUV/foreman_352x288_30Hz_i420_8.y4m -an -preset faster > >> -vcodec vvc test.mp4 > >> > >> -> encodes 300 frames. > >> > >> Decode to YUV (or play back using ffplay): > >> ./ffmpeg -i test.mp4 test.yuv > >> > >> -> outputs 271 frames > >> > >> When dumping the mp4-structure using 'MP4Box -diso test.mp4', I see the > >> following EditListBox, which skips the first couple of > >> frames:<EditListBox Size="40" Type="elst" Version="0" Flags="0" > >> Specification="p12" Container="edts" EntryCount="2"> > >> <EditListEntry Duration="1033" MediaTime="-1" MediaRate="1"/> > >> <EditListEntry Duration="8967" MediaTime="18432" MediaRate="1"/> > >> </EditListBox> > >> > >> > >> With the fix applied 300 frames are decoded as expected and the > >> EditListBox looks like this: > >> <EditListBox Size="28" Type="elst" Version="0" Flags="0" > >> Specification="p12" Container="edts" EntryCount="1"> > >> <EditListEntry Duration="10000" MediaTime="2560" MediaRate="1"/> > >> </EditListBox> > >> _______________________________________________ > >> 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". > >> > > _______________________________________________ > > 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". > > _______________________________________________ > 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". > _______________________________________________ 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".
