[FFmpeg-trac] #5121(undetermined:new): Wrong sample rate read from / written to opus webm file

[FFmpeg]

#5121: Wrong sample rate read from / written to opus webm file
-------------------------------------+-------------------------------------
             Reporter:  pszemus      |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:
              Version:  unspecified  |  undetermined
             Keywords:               |               Resolution:
             Blocking:               |               Blocked By:
Analyzed by developer:  0            |  Reproduced by developer:  0
-------------------------------------+-------------------------------------

Comment (by pszemus):

 No, I want the ffmpeg to create with and report the correct sample rate
 value.
 Let's create an opus file like this:
 {{{
 $ ffmpeg -i
 http://www.soundsnap.com/audio/play/72210%3A1448291371%3Ab4326304c013a3a61b3b87d83158c91b
 -c:a libopus -b:a 64k -ar 24000 /tmp/tmp.opus
 ffmpeg version N-77704-g68eb208 Copyright (c) 2000-2016 the FFmpeg
 developers
   built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-4)
   configuration: --prefix=/home/pszemus/ffmpeg/build --enable-pic
 --enable-pthreads --enable-libmp3lame --enable-version3 --enable-libfaac
 --enable-gpl --enable-nonfree --enable-libvpx --enable-libvorbis --enable-
 libopus --enable-libx264 --enable-libwebp --enable-protocol=https
 --enable-openssl --extra-cflags=-I/opt/WP/common.libs/include --extra-
 ldflags='-L/opt/WP/common.libs/lib -ldl'
   libavutil      55. 12.100 / 55. 12.100
   libavcodec     57. 21.100 / 57. 21.100
   libavformat    57. 21.100 / 57. 21.100
   libavdevice    57.  0.100 / 57.  0.100
   libavfilter     6. 23.100 /  6. 23.100
   libswscale      4.  0.100 /  4.  0.100
   libswresample   2.  0.101 /  2.  0.101
   libpostproc    54.  0.100 / 54.  0.100
 [mp3 @ 0x3c683a0] Skipping 0 bytes of junk at 0.
 [mp3 @ 0x3c683a0] Estimating duration from bitrate, this may be inaccurate
 Input #0, mp3, from
 'http://www.soundsnap.com/audio/play/72210%3A1448291371%3Ab4326304c013a3a61b3b87d83158c91b':
   Metadata:
     title           : PleaseRefesh2015_1
     date            : 2015
     track           : 1
   Duration: 00:00:04.13, start: 0.000000, bitrate: 192 kb/s
     Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 192 kb/s
 Output #0, opus, to '/tmp/tmp.opus':
   Metadata:
     title           : PleaseRefesh2015_1
     date            : 2015
     track           : 1
     encoder         : Lavf57.21.100
     Stream #0:0: Audio: opus (libopus), 24000 Hz, stereo, s16, 64 kb/s
     Metadata:
       encoder         : Lavc57.21.100 libopus
       title           : PleaseRefesh2015_1
       date            : 2015
       TRACKNUMBER     : 1
 Stream mapping:
   Stream #0:0 -> #0:0 (mp3 (native) -> opus (libopus))
 Press [q] to stop, [?] for help
 size=      36kB time=00:00:04.13 bitrate=  71.0kbits/s speed=15.3x
 video:0kB audio:35kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 1.533776%
 }}}
 Now compare the output form FFmpeg and opusinfo (from opus-tools)
 analysis:
 {{{
 $ ffmpeg -i /tmp/tmp.opus
 ffmpeg version N-77704-g68eb208 Copyright (c) 2000-2016 the FFmpeg
 developers
   built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-4)
   configuration: --prefix=/home/pszemus/ffmpeg/build --enable-pic
 --enable-pthreads --enable-libmp3lame --enable-version3 --enable-libfaac
 --enable-gpl --enable-nonfree --enable-libvpx --enable-libvorbis --enable-
 libopus --enable-libx264 --enable-libwebp --enable-protocol=https
 --enable-openssl --extra-cflags=-I/opt/WP/common.libs/include --extra-
 ldflags='-L/opt/WP/common.libs/lib -ldl'
   libavutil      55. 12.100 / 55. 12.100
   libavcodec     57. 21.100 / 57. 21.100
   libavformat    57. 21.100 / 57. 21.100
   libavdevice    57.  0.100 / 57.  0.100
   libavfilter     6. 23.100 /  6. 23.100
   libswscale      4.  0.100 /  4.  0.100
   libswresample   2.  0.101 /  2.  0.101
   libpostproc    54.  0.100 / 54.  0.100
 Input #0, ogg, from '/tmp/tmp.opus':
   Duration: 00:00:04.13, start: 0.000000, bitrate: 70 kb/s
     Stream #0:0: Audio: opus, 48000 Hz, stereo, fltp
     Metadata:
       ENCODER         : Lavc57.21.100 libopus
       TITLE           : PleaseRefesh2015_1
       DATE            : 2015
       track           : 1
 At least one output file must be specified
 }}}
 {{{
 $ opusinfo /tmp/tmp.opus
 Processing file "/tmp/tmp.opus"...

 New logical stream (#1, serial: 281a7d51): type opus
 Encoded with Lavf57.21.100
 User comments section follows...
         encoder=Lavc57.21.100 libopus
         title=PleaseRefesh2015_1
         date=2015
         TRACKNUMBER=1
 Opus stream 1:
         Pre-skip: 156
         Playback gain: 0 dB
         Channels: 2
         Original sample rate: 24000Hz
         Packet duration:   20.0ms (max),   20.0ms (avg),   20.0ms (min)
         Page duration:   1000.0ms (max),  828.0ms (avg),  140.0ms (min)
         Total data length: 36674 bytes (overhead: 1.51%)
         Playback length: 0m:04.130s
         Average bitrate: 71.03 kb/s, w/o overhead: 69.96 kb/s
 Logical stream 1 ended
 }}}
 Where this inconsistency come from? Why does FFmpeg and Firefox report
 48kHz sample rate when MediaInfo and opusinfo show 24kHz?

--
Ticket URL: <https://trac.ffmpeg.org/ticket/5121#comment:2>
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