[FFmpeg-trac] #9821(avformat:new): Rewarp MPEGDash to MP4 changes audio bitrate mode

[FFmpeg]

#9821: Rewarp MPEGDash to MP4 changes audio bitrate mode
-------------------------------------+-------------------------------------
             Reporter:  Matth        |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avformat     |                  Version:  git-
             Keywords:  DASH         |  master
  bitrate mp4                        |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:

 On a windows machine, i'm rewrapping some MPEGDash to MP4 wrapper and some
 files are outputed with variable audio bitrate where others with constant
 bitrate,and both sources looks exactly the same.

 How to reproduce:
 {{{
 .\ffmpeg.exe -y -i MPEGDash_A0002_30sec.mpd -map 0:v -map 0:a -c copy
 OutFile.mp4

 ffmpeg version 5.0-full_build-www.gyan.dev Copyright (c) 2000-2022 the
 FFmpeg developers
 built with gcc 11.2.0 (Rev5, Built by MSYS2 project)
 configuration: --enable-gpl --enable-version3 --enable-static --disable-
 w32threads --disable-autodetect --enable-fontconfig --enable-iconv
 --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma
 --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt
 --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray
 --enable-libcaca --enable-sdl2 --enable-libdav1d --enable-libdavs2
 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1
 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2
 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx
 --enable-mediafoundation --enable-libass --enable-frei0r --enable-
 libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf
 --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-
 ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2
 --enable-libmfx --enable-libshaderc --enable-vulkan --enable-libplacebo
 --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug
 --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame
 --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-
 amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb
 --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa
 --enable-libbs2b --enable-libflite --enable-libmysofa --enable-
 librubberband --enable-libsoxr --enable-chromaprint
 libavutil      57. 17.100 / 57. 17.100
 libavcodec     59. 18.100 / 59. 18.100
 libavformat    59. 16.100 / 59. 16.100
 libavdevice    59.  4.100 / 59.  4.100
 libavfilter     8. 24.100 /  8. 24.100
 libswscale      6.  4.100 /  6.  4.100
 libswresample   4.  3.100 /  4.  3.100
 libpostproc    56.  3.100 / 56.  3.100
 }}}


 * This source MPEGDASH with constant audio bitrate
 (_MediaInfo_MPEGDash_A0002_30sec.Dash.txt)
 * Has the expected output with constant audio bitrate on the MP4
 (_MediaInfo_A0002_30sec.mp4.txt)

 * But this source MPEGDASH which has the same characteristics
 (_MediaInfo_MPEGDash_A0005_30sec.Dash.txt)
 * Has this output where the MP4 have the first audio with variable bitrate
 (_MediaInfo_A0005_30sec.mp4.txt)

 I can upload the source Dash packages if needed.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9821>
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