[FFmpeg-trac] #1299(undetermined:new): shorten: support signal to noise ratio mode (lossy coding)

[FFmpeg]

#1299: shorten: support signal to noise ratio mode (lossy coding)
-------------------------------------+-------------------------------------
               Reporter:  ami_stuff  |                  Owner:
                   Type:  defect     |                 Status:  new
               Priority:  normal     |              Component:
                Version:             |  undetermined
  unspecified                        |               Keywords:
             Blocked By:             |               Blocking:
Reproduced by developer:  0          |  Analyzed by developer:  0
-------------------------------------+-------------------------------------
 currently the output is incorrect (audio distortion or silence)

 shorten -n 8 test.wav n8.shn

 http://www.datafilehost.com/download-b8386697.html

 {{{
   -n 256   minimum signal to noise ratio in dB (256 == lossless coding)
 }}}

 {{{
 C:\ffmpeg -i n8.shn out.wav
 ffmpeg version N-40511-g66337bf Copyright (c) 2000-2012 the FFmpeg
 developers
   built on May  9 2012 02:38:42 with gcc 4.5.0 20100414 (Fedora MinGW
 4.5.0-1.fc
 14)
   configuration: --prefix=/var/www/users/research/ffmpeg/snapshots/build
 --arch=
 x86 --target-os=mingw32 --cross-prefix=i686-pc-mingw32- --cc='ccache i686
 -pc-min
 gw32-gcc' --enable-w32threads --enable-memalign-hack --enable-runtime-
 cpudetect
 --enable-cross-compile --enable-static --disable-shared --extra-
 libs='-lws2_32 -
 lwinmm' --extra-cflags='--static
 -I/var/www/users/research/ffmpeg/snapshots/buil
 d/include' --extra-ldflags='-static
 -L/var/www/users/research/ffmpeg/snapshots/b
 uild/lib' --enable-bzlib --enable-zlib --enable-gpl --enable-version3
 --enable-n
 onfree --enable-libx264 --enable-libspeex --enable-libtheora --enable-
 libvorbis
 --enable-libfaac --enable-libxvid --enable-libopencore-amrnb --enable-
 libopencor
 e-amrwb --enable-libmp3lame --enable-libvpx --disable-decoder=libvpx
   libavutil      51. 50.100 / 51. 50.100
   libavcodec     54. 21.100 / 54. 21.100
   libavformat    54.  4.100 / 54.  4.100
   libavdevice    53.  4.100 / 53.  4.100
   libavfilter     2. 72.105 /  2. 72.105
   libswscale      2.  1.100 /  2.  1.100
   libswresample   0. 11.100 /  0. 11.100
   libpostproc    52.  0.100 / 52.  0.100
 [shorten @ 0x1dc2320] 2 header bytes unparsed
 [shn @ 0x1dcc5c0] Estimating duration from bitrate, this may be inaccurate
 Input #0, shn, from 'n8.shn':
   Duration: N/A, start: 0.000000, bitrate: N/A
     Stream #0:0: Audio: shorten, 44100 Hz, 2 channels, s16
 Guessed Channel Layout for  Input Stream #0.0 : stereo
 Output #0, wav, to 'out.wav':
   Metadata:
     encoder         : Lavf54.4.100
     Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz,
 stereo, s16
 , 1411 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (shorten -> pcm_s16le)
 Press [q] to stop, [?] for help
 [shorten @ 0x1dc2320] 2 header bytes unparsed
 Input stream #0:0 frame changed from rate:44100 fmt:s16 ch:2 chl:0x0 to
 rate:441
 00 fmt:s16 ch:2 chl:0x3
 Multiple frames in a packet from stream 0
 size=    1724kB time=00:00:10.00 bitrate=1411.5kbits/s
 video:0kB audio:1724kB global headers:0kB muxing overhead 0.002606%
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/1299>
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