[FFmpeg-trac] #10168(undetermined:new): pan audiofilter regression

[FFmpeg]

#10168: pan audiofilter regression
-------------------------------------+-------------------------------------
             Reporter:  Jose         |                     Type:  defect
  Peirote                            |
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:  pan          |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 the pan audiofilter work fine in 4.4 version with a simple downmix:

 ffmpeg -i 8v341.dts -filter_complex "asplit [f][s]; [f]
 pan=FL+FR+FC+LFE|FL=FL|FR=FR|FC=FC|LFE=LFE [r]; [s]
 pan=SL+SR|c0=0.5*c4+0.5*c6|c1=0.5*c5+0.5*c7 [d]; [r][d] amerge [a]" -map
 "[a]" -acodec pcm_s24le 8v341_44.wav
 ffmpeg version n4.4.3-3-gb48951bd29-20230204 Copyright (c) 2000-2022 the
 FFmpeg developers
   built with gcc 12.2.0 (crosstool-NG 1.25.0.90_cf9beb1)
   libavutil      56. 70.100 / 56. 70.100
   libavcodec     58.134.100 / 58.134.100
 ...
 Input #0, dts, from 'C:\tmp\8v341.dts':
   Stream #0:0: Audio: dts (DTS-HD MA), 48000 Hz, 7.1, s32p (24 bit)
 [Parsed_pan_1 @ 00000201ed440dc0] Pure channel mapping detected: 0 1 2 3
 Output #0, wav, to 'C:\tmp\8v341_144.wav':
   Stream #0:0: Audio: pcm_s24le ([1][0][0][0] / 0x0001), 48000 Hz,
 5.1(side), s32 (24 bit), 6912 kb/s
       encoder         : Lavc58.134.100 pcm_s24le

 But using a 5.1 version:

 ffmpeg -i 8v341.dts -filter_complex "asplit [f][s]; [f]
 pan=FL+FR+FC+LFE|FL=FL|FR=FR|FC=FC|LFE=LFE [r]; [s]
 pan=SL+SR|c0=0.5*c4+0.5*c6|c1=0.5*c5+0.5*c7 [d]; [r][d] amerge [a]" -map
 "[a]" -acodec pcm_s24le 8v341_51.wav
 ffmpeg version n5.1.2-11-g30d432f205-20230204 Copyright (c) 2000-2022 the
 FFmpeg developers
   built with gcc 12.2.0 (crosstool-NG 1.25.0.90_cf9beb1)
   libavutil      57. 28.100 / 57. 28.100
   libavcodec     59. 37.100 / 59. 37.100
 ...
 Input #0, dts, from 'C:\tmp\8v341.dts':
   Stream #0:0: Audio: dts (DTS-HD MA), 48000 Hz, 7.1, s32p (24 bit)
 [Parsed_pan_1 @ 000001d1d89f05c0] [SWR @ 000001d1d8a400c0] Input channel
 layout has a different number of channels than the number of used
 channels, ignoring layout  ????
 [Parsed_pan_1 @ 000001d1d89f05c0] Pure channel mapping detected: 0 1 2 3
 Output #0, wav, to 'C:\tmp\8v341.dtshd_.dts_151.wav':
   Stream #0:0: Audio: pcm_s24le ([1][0][0][0] / 0x0001), 48000 Hz,
 5.1(side), s32, 6912 kb/s
       encoder         : Lavc59.37.100 pcm_s24le

 there are a new and wrong message and the output is wrong (LFE input
 channel mixed 50% in FL and FR channels, empty LFE output channel.
 See the image
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10168>
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