[FFmpeg-trac] #11619(undetermined:new): OPUS downmix volume clipping

[FFmpeg]

#11619: OPUS downmix volume clipping
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             Reporter:  Marco         |                     Type:  defect
               Status:  new           |                 Priority:  normal
            Component:  undetermined  |                  Version:  7.1
             Keywords:  libopus       |               Blocked By:
             Blocking:                |  Reproduced by developer:  0
Analyzed by developer:  0             |
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 (I'm using version 7.1.1, the one shipped with Fedora 42)

 When downmixing a 5.1 surround track from a film (any film actually) to a
 stereo 2.0 opus track, the output stereo track seems to be clipping when
 opened with Tenacity (fork of Audacity).
 This is the command I used to convert the 5.1 track to 2.0 opus:
 {{{
 ffmpeg -i audio.mka -c:a libopus -b:a 128k -ac 2 audio.opus
 }}}
 I also tried the following command:
 {{{
 ffmpeg -i audio.mka -ac 2 audio.wav
 }}}
 Comparing the output of both commands in Tenacity, I notice a volume
 increase in the OPUS track compared to the WAV one, and that makes the
 volume clip in many parts.
 Is there something I'm misunderstanding? The outputs should look similar,
 they are not.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/11619>
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