[FFmpeg-trac] #169(undetermined:new): IFF 8SVX stereo files (with FIB/EXP compression) decodes incorrectly

[FFmpeg]

#169: IFF 8SVX stereo files (with FIB/EXP compression) decodes incorrectly
--------------------------+--------------------------
 Reporter:  ami_stuff     |        Type:  defect
   Status:  new           |    Priority:  normal
Component:  undetermined  |     Version:  unspecified
 Keywords:                |  Blocked By:
 Blocking:                |  Reproduced:  0
 Analyzed:  0             |
--------------------------+--------------------------
 Issue 1589 (& Issue 1427)

 Attached files decodes incorrectly.

 Please see

 https://roundup.libav.org/issue1427

 for more info as well.


 {{{
 Author: ami_stuff       Date: 2009-12-05.02:37:04

 >> What about 8SVX_FIB/EXP 2 channel files? This looks like it is just
 >> correct for 8bit PCM.

 > The "spec" and sketchy documentation available do not say anything about
 > stereo 8svx compressed sampling. My assumption is that such samples are
 not
 > defined. Same goes for 16bit stereo samples. IIRC we only have one
 compressed
 > sample available and that is mono.
 > More importantly, stereo samples are present in a number of anim files,
 which
 > are again uncompressed.
 > I'll be happy to add functionality as and when samples surface.

 Here are compressed IFF 8SVX stereo files. These files don't sound "clean"
 and
 of course too fast - issue1427.

 There is also availabe sourcecode of decoder and encoder:

 http://aminet.net/package/mus/misc/wavepak

 C:\>ffmpeg -i 8svx_exp.iff
 FFmpeg version SVN-r20726, Copyright (c) 2000-2009 Fabrice Bellard, et al.
   built on Dec  4 2009 06:03:38 with gcc 4.2.4
   configuration: --enable-memalign-hack --prefix=/mingw --cross-
 prefix=i686-ming
 w32- --cc=ccache-i686-mingw32-gcc --target-os=mingw32 --arch=i686
 --cpu=i686 --e
 nable-avisynth --enable-gpl --enable-version3 --enable-zlib --enable-bzlib
 --ena
 ble-libgsm --enable-libfaad --enable-pthreads --enable-libvorbis --enable-
 libthe
 ora --enable-libspeex --enable-libmp3lame --enable-libopenjpeg --enable-
 libxvid
 --enable-libschroedinger --enable-libx264 --enable-libopencore_amrwb
 --enable-li
 bopencore_amrnb
   libavutil     50. 5. 1 / 50. 5. 1
   libavcodec    52.42. 0 / 52.42. 0
   libavformat   52.40. 0 / 52.40. 0
   libavdevice   52. 2. 0 / 52. 2. 0
   libswscale     0. 7. 2 /  0. 7. 2
 [IFF @ 0x3eced0]Estimating duration from bitrate, this may be inaccurate
 Input #0, IFF, from '8svx_exp.iff':
   Duration: 00:00:02.53, start: 0.000000, bitrate: 705 kb/s
     Stream #0.0: Audio: 8svx_exp, 44100 Hz, 2 channels, s16, 705 kb/s
 At least one output file must be specified


 C:\>ffmpeg -i 8svx_fib.iff
 FFmpeg version SVN-r20726, Copyright (c) 2000-2009 Fabrice Bellard, et al.
   built on Dec  4 2009 06:03:38 with gcc 4.2.4
   configuration: --enable-memalign-hack --prefix=/mingw --cross-
 prefix=i686-ming
 w32- --cc=ccache-i686-mingw32-gcc --target-os=mingw32 --arch=i686
 --cpu=i686 --e
 nable-avisynth --enable-gpl --enable-version3 --enable-zlib --enable-bzlib
 --ena
 ble-libgsm --enable-libfaad --enable-pthreads --enable-libvorbis --enable-
 libthe
 ora --enable-libspeex --enable-libmp3lame --enable-libopenjpeg --enable-
 libxvid
 --enable-libschroedinger --enable-libx264 --enable-libopencore_amrwb
 --enable-li
 bopencore_amrnb
   libavutil     50. 5. 1 / 50. 5. 1
   libavcodec    52.42. 0 / 52.42. 0
   libavformat   52.40. 0 / 52.40. 0
   libavdevice   52. 2. 0 / 52. 2. 0
   libswscale     0. 7. 2 /  0. 7. 2
 [IFF @ 0x3ecee0]Estimating duration from bitrate, this may be inaccurate
 Input #0, IFF, from '8svx_fib.iff':
   Duration: 00:00:02.53, start: 0.000000, bitrate: 705 kb/s
     Stream #0.0: Audio: 8svx_fib, 44100 Hz, 2 channels, s16, 705 kb/s
 At least one output file must be specified
 }}}

 {{{
 Author: BastyCDGS       Date: 2010-05-05.18:58:18

 I've done an analysis of this and found out that the decoder trys to
 interleave
 stereo samples to packet buffer and not to the whole length of BODY chunk.

 Fix will be pretty straight forward, I think...but I'm busy right now with
 IFF-ILBM and IFF-ANIM, so please be patient.
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/169>
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