[FFmpeg-trac] #11683(avcodec:new): Error encoding to H265 (H264 is ok)

[FFmpeg]

#11683: Error encoding to H265 (H264 is ok)
-------------------------------------+-------------------------------------
             Reporter:  rgr          |                     Type:  defect
               Status:  new          |                 Priority:  important
            Component:  avcodec      |                  Version:  7.1
             Keywords:  h265         |               Blocked By:
  encoding                           |
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 The encoded MP4/H265 file doesn't play correctly and is 2 frames shorter.
 When I change the codec to H264, everything works fine.

 ffmpeg reports 465 frames encoded:
 encoded 465 frames in 46.29s (10.05 fps), 8883.04 kb/s, Avg QP:25.39
 [aac @ 000001c87a123040] Qavg: 881.112

 In VirtualDub with the latest ffmpeg libraries, the last frames are
 displayed in random order. Seek-by-frame often causes jumps to the wrong
 frame (each frame has a label with its number). Magix Vegas only reads 463
 frames.
 After changing the codec in the ffmpeg command to libx264, all problems
 disappear.

 https://gcdnb.pbrd.co/images/ZSD7tRo9KuG7.png?o=1

 How to reproduce:
 {{{
 % ffmpeg -avisynth_flags +all -i "2025_04_10 20_44_52
 (PXL_20250410_204452830).avs" -c:v libx265 -preset slow -crf 19 -pix_fmt
 yuv420p -c:a aac -b:a 192k "2025_04_10 20_44_52
 (PXL_20250410_204452830)(H265).mp4"

 ffmpeg version 2025-07-23-git-829680f96a-full_build-www.gyan.dev
 built on 2025-07-23
 }}}

 Files: https://files.fm/u/jq3yzf4za7 (output H265 included)
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/11683>
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