[FFmpeg-trac] #10521(undetermined:new): ACC encoder speed degradation in version 5.x.x and above

[FFmpeg]

#10521: ACC encoder speed degradation in version 5.x.x and above
-------------------------------------+-------------------------------------
             Reporter:  Vexs         |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |
             Keywords:  aac speed    |               Blocked By:
  performance                        |
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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 Summary of the bug:

 AAC encoder speed is degraded in version 5.x and above

 How to reproduce:

 1. Download test aac file
 https://filesamples.com/samples/audio/aac/sample4.aac

 2. Download ffmpeg version 4.4.1 from https://www.johnvansickle.com/ffmpeg
 /old-releases/ or compile from branch
 https://github.com/FFmpeg/FFmpeg/tree/release/4.4

 3. Download ffmpeg version 5.1.1 from https://www.johnvansickle.com/ffmpeg
 /old-releases/ or compile from branch
 https://github.com/FFmpeg/FFmpeg/tree/release/5.1

 4. Run command ffmpeg-5.1.1 -y -i sample4.aac -strict strict -b:a 128000
 -vn tmp.aac

 5. Run command ffmpeg-4.4.1 -y -i sample4.aac -strict strict -b:a 128000
 -vn tmp.aac

 6. Compare speed 5.1.1 speed=~26.5x vs 4.4.1 speed=~79.9x

 Additional informations:

 1. It seems that only the aac format has this problem. Another audio
 codecs encoding speed is ok

 2. This only applies to encoding. AAC decoding speed looks ok

 3. In all 4.x.x version encoding speed is ok. Starting from 5.x speed is
 degraded
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Ticket URL: <https://trac.ffmpeg.org/ticket/10521>
FFmpeg <https://ffmpeg.org>
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