[FFmpeg-trac] #9403(undetermined:new): Cannot decode .caf file streamed from stdin

[FFmpeg]

#9403: Cannot decode .caf file streamed from stdin
-------------------------------------+-------------------------------------
             Reporter:               |                     Type:  defect
  pjshumphreys                       |
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:  caf          |               Blocked By:
  streaming                          |
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 How to reproduce:
 {{{
 % cat input.caf | ffmpeg -i - -ac 1 -ar 16000 -f f32le - > output.raw

 This command produces a zero byte output file, even though the stream
 format was detected:

 ffmpeg version 4.4 Copyright (c) 2000-2021 the FFmpeg developers
   built with Apple clang version 12.0.5 (clang-1205.0.22.9)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/4.4_2 --enable-shared
 --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-
 ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom
 --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus
 --enable-librav1e --enable-librubberband --enable-libsnappy --enable-
 libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab
 --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264
 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-
 libfontconfig --enable-libfreetype --enable-frei0r --enable-libass
 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg
 --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg
 --disable-libjack --disable-indev=jack --enable-avresample --enable-
 videotoolbox
   libavutil      56. 70.100 / 56. 70.100
   libavcodec     58.134.100 / 58.134.100
   libavformat    58. 76.100 / 58. 76.100
   libavdevice    58. 13.100 / 58. 13.100
   libavfilter     7.110.100 /  7.110.100
   libavresample   4.  0.  0 /  4.  0.  0
   libswscale      5.  9.100 /  5.  9.100
   libswresample   3.  9.100 /  3.  9.100
   libpostproc    55.  9.100 / 55.  9.100
 Guessed Channel Layout for Input Stream #0.0 : mono
 Input #0, caf, from 'pipe:':
   Duration: N/A, start: 0.000000, bitrate: 1536 kb/s
   Stream #0:0: Audio: pcm_f32le (lpcm / 0x6D63706C), 48000 Hz, mono, flt,
 1536 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_f32le (native) -> pcm_f32le (native))
 Output #0, f32le, to 'pipe:':
   Metadata:
     encoder         : Lavf58.76.100
   Stream #0:0: Audio: pcm_f32le, 16000 Hz, mono, flt, 512 kb/s
     Metadata:
       encoder         : Lavc58.134.100 pcm_f32le
 size=       0kB time=00:00:00.00 bitrate=N/A speed=   0x
 video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown
 Output file is empty, nothing was encoded (check -ss / -t / -frames
 parameters if used)



 However, if the file is read by ffmpeg directly then output is returned:

 % ffmpeg -i input.caf -ac 1 -ar 16000 -f f32le - > output.raw

 ffmpeg version 4.4 Copyright (c) 2000-2021 the FFmpeg developers
   built with Apple clang version 12.0.5 (clang-1205.0.22.9)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/4.4_2 --enable-shared
 --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-
 ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom
 --enable-libbluray --enable-libdav1d --enable-libmp3lame --enable-libopus
 --enable-librav1e --enable-librubberband --enable-libsnappy --enable-
 libsrt --enable-libtesseract --enable-libtheora --enable-libvidstab
 --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264
 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-
 libfontconfig --enable-libfreetype --enable-frei0r --enable-libass
 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg
 --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg
 --disable-libjack --disable-indev=jack --enable-avresample --enable-
 videotoolbox
   libavutil      56. 70.100 / 56. 70.100
   libavcodec     58.134.100 / 58.134.100
   libavformat    58. 76.100 / 58. 76.100
   libavdevice    58. 13.100 / 58. 13.100
   libavfilter     7.110.100 /  7.110.100
   libavresample   4.  0.  0 /  4.  0.  0
   libswscale      5.  9.100 /  5.  9.100
   libswresample   3.  9.100 /  3.  9.100
   libpostproc    55.  9.100 / 55.  9.100
 [caf @ 0x7fb63c809400] Estimating duration from bitrate, this may be
 inaccurate
 Guessed Channel Layout for Input Stream #0.0 : mono
 Input #0, caf, from 'input.caf':
   Duration: 00:00:05.80, start: 0.000000, bitrate: 1541 kb/s
   Stream #0:0: Audio: pcm_f32le (lpcm / 0x6D63706C), 48000 Hz, mono, flt,
 1536 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_f32le (native) -> pcm_f32le (native))
 Press [q] to stop, [?] for help
 Output #0, f32le, to 'pipe:':
   Metadata:
     encoder         : Lavf58.76.100
   Stream #0:0: Audio: pcm_f32le, 16000 Hz, mono, flt, 512 kb/s
     Metadata:
       encoder         : Lavc58.134.100 pcm_f32le
 size=     362kB time=00:00:05.79 bitrate= 512.1kbits/s speed= 675x
 video:0kB audio:362kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: 0.000000%


 ffmpeg version 4.4_2

 }}}
 Patches should be submitted to the ffmpeg-devel mailing list and not this
 bug tracker.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9403>
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