[FFmpeg-trac] #2759(FFmpeg:new): Audio equalizer filter problem - clipping with negative gain

[FFmpeg]

#2759: Audio equalizer filter problem  - clipping with negative gain
--------------------------------+--------------------------------------
             Reporter:  Ajaja   |                     Type:  defect
               Status:  new     |                 Priority:  normal
            Component:  FFmpeg  |                  Version:  git-master
             Keywords:          |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
--------------------------------+--------------------------------------
 How to reproduce:
 {{{
 % ffmpeg -f lavfi -i aevalsrc="1.98*random(0)-0.99" -to 60 noise.wav
 ...

 % ffmpeg -i noise.wav -af equalizer=2000:q:1:-5  noise2.wav
 ffmpeg version N-54499-g63d7684 Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Jul  6 2013 10:35:18 with gcc 4.7.3 (GCC)
   configuration: --enable-gpl --enable-version3 --disable-w32threads
 --enable-avisynth --enable-bzlib --enable-fontconfig --enab
 le-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-
 libbluray --enable-libcaca --enable-libfreetype --enable-libgs
 m --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-
 libopencore-amrnb --enable-libopencore-amrwb --enable-libope
 njpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-
 libsoxr --enable-libspeex --enable-libtheora --enable-
 libtwolame --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-
 libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --
 enable-libxvid --enable-zlib
   libavutil      52. 38.100 / 52. 38.100
   libavcodec     55. 18.102 / 55. 18.102
   libavformat    55. 11.101 / 55. 11.101
   libavdevice    55.  2.100 / 55.  2.100
   libavfilter     3. 78.102 /  3. 78.102
   libswscale      2.  3.100 /  2.  3.100
   libswresample   0. 17.102 /  0. 17.102
   libpostproc    52.  3.100 / 52.  3.100
 Guessed Channel Layout for  Input Stream #0.0 : mono
 Input #0, wav, from 'noise.wav':
   Metadata:
     encoder         : Lavf55.11.101
   Duration: 00:01:00.00, bitrate: 705 kb/s
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, mono,
 s16, 705 kb/s
 Output #0, wav, to 'noise2.wav':
   Metadata:
     ISFT            : Lavf55.11.101
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, mono,
 s16, 705 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
 Press [q] to stop, [?] for help
 clipping
     Last message repeated 654 times
 clipping  120kB time=00:00:01.39 bitrate= 706.1kbits/s
     Last message repeated 651 times
 clipping  236kB time=00:00:02.73 bitrate= 705.8kbits/s
     Last message repeated 653 times
 clipping  352kB time=00:00:04.08 bitrate= 705.8kbits/s
     Last message repeated 662 times
 clipping  476kB time=00:00:05.52 bitrate= 705.7kbits/s
     Last message repeated 653 times
 clipping  604kB time=00:00:07.01 bitrate= 705.7kbits/s
     Last message repeated 649 times
 clipping  720kB time=00:00:08.35 bitrate= 705.7kbits/s
     Last message repeated 654 times
 clipping  848kB time=00:00:09.84 bitrate= 705.7kbits/s
     Last message repeated 672 times
 .....
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2759>
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