[FFmpeg-trac] #1727(avfilter:new): volumedetect filter doesn't work with -t

[FFmpeg]

#1727: volumedetect filter doesn't work with -t
-------------------------------------+-------------------------------------
             Reporter:  dericed      |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avfilter     |                  Version:  git-
             Keywords:               |  master
  volumedetect                       |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:

 The volumedetect filter doesn't seem to work if -t is used. I'd like to
 use volumedetect to analyze the first N seconds of a video rather than the
 whole file, but if I use -t than there is no output to the volumedetect
 filter.

 How to reproduce:

 Without -t
 {{{
 ffmpeg -i audio.wav -af volumedetect -f null -
 ffmpeg version 0.11.1.git Copyright (c) 2000-2012 the FFmpeg developers
   built on Aug 19 2012 22:28:01 with gcc 4.2.1 (GCC) (Apple Inc. build
 5666) (dot 3)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/HEAD --enable-shared
 --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables
 --enable-libfreetype --cc=/usr/bin/gcc-4.2 --host-cflags='-Os -w -pipe
 -march=core2 -mmacosx-version-min=10.7' --host-
 ldflags='-L/usr/local/Cellar/libtool/2.4.2/lib
 -L/usr/local/Cellar/automake/1.12.2/lib
 -L/usr/local/Cellar/autoconf/2.69/lib
 -L/usr/local/Cellar/gettext/0.18.1.1/lib -L/usr/local/lib -L/usr/X11/lib'
 --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-librtmp
 --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libxvid
 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass
 --enable-libvo-aacenc --enable-libopenjpeg
   libavutil      51. 70.100 / 51. 70.100
   libavcodec     54. 53.100 / 54. 53.100
   libavformat    54. 25.104 / 54. 25.104
   libavdevice    54.  2.100 / 54.  2.100
   libavfilter     3. 11.101 /  3. 11.101
   libswscale      2.  1.101 /  2.  1.101
   libswresample   0. 15.100 /  0. 15.100
   libpostproc    52.  0.100 / 52.  0.100
 [wav @ 0x7fb30883d800] max_analyze_duration 5000000 reached at 5013333
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Input #0, wav, from 'audio.wav':
   Duration: 00:00:10.00, bitrate: 1536 kb/s
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz,
 stereo, s16, 1536 kb/s
 Output #0, null, to 'pipe:':
   Metadata:
     encoder         : Lavf54.25.104
     Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
 Press [q] to stop, [?] for help
 [Parsed_volumedetect_0 @ 0x7fb308420580] n_samples: 960800
 [Parsed_volumedetect_0 @ 0x7fb308420580] mean_volume: -51.3 dB
 [Parsed_volumedetect_0 @ 0x7fb308420580] max_volume: -33.9 dB
 [Parsed_volumedetect_0 @ 0x7fb308420580] histogram_33db: 3
 [Parsed_volumedetect_0 @ 0x7fb308420580] histogram_34db: 43
 [Parsed_volumedetect_0 @ 0x7fb308420580] histogram_35db: 88
 [Parsed_volumedetect_0 @ 0x7fb308420580] histogram_36db: 280
 [Parsed_volumedetect_0 @ 0x7fb308420580] histogram_37db: 667
 size=       0kB time=00:00:10.00 bitrate=   0.0kbits/s
 video:0kB audio:1877kB subtitle:0 global headers:0kB muxing overhead
 -100.000000%
 }}}

 With -t
 {{{
 ffmpeg -i audio.wav -t 2 -af volumedetect -f null -
 ffmpeg version 0.11.1.git Copyright (c) 2000-2012 the FFmpeg developers
   built on Aug 19 2012 22:28:01 with gcc 4.2.1 (GCC) (Apple Inc. build
 5666) (dot 3)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/HEAD --enable-shared
 --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables
 --enable-libfreetype --cc=/usr/bin/gcc-4.2 --host-cflags='-Os -w -pipe
 -march=core2 -mmacosx-version-min=10.7' --host-
 ldflags='-L/usr/local/Cellar/libtool/2.4.2/lib
 -L/usr/local/Cellar/automake/1.12.2/lib
 -L/usr/local/Cellar/autoconf/2.69/lib
 -L/usr/local/Cellar/gettext/0.18.1.1/lib -L/usr/local/lib -L/usr/X11/lib'
 --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-librtmp
 --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libxvid
 --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass
 --enable-libvo-aacenc --enable-libopenjpeg
   libavutil      51. 70.100 / 51. 70.100
   libavcodec     54. 53.100 / 54. 53.100
   libavformat    54. 25.104 / 54. 25.104
   libavdevice    54.  2.100 / 54.  2.100
   libavfilter     3. 11.101 /  3. 11.101
   libswscale      2.  1.101 /  2.  1.101
   libswresample   0. 15.100 /  0. 15.100
   libpostproc    52.  0.100 / 52.  0.100
 [wav @ 0x7ff10103d800] max_analyze_duration 5000000 reached at 5013333
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Input #0, wav, from 'audio.wav':
   Duration: 00:00:10.00, bitrate: 1536 kb/s
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz,
 stereo, s16, 1536 kb/s
 Output #0, null, to 'pipe:':
   Metadata:
     encoder         : Lavf54.25.104
     Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
 Press [q] to stop, [?] for help
 size=       0kB time=00:00:02.00 bitrate=   0.0kbits/s
 video:0kB audio:376kB subtitle:0 global headers:0kB muxing overhead
 -100.000000%
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/1727>
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