[FFmpeg-trac] #4714(avcodec:new): wmalossless decoder is not lossless

FFmpeg trac at avcodec.org
Sun Jul 12 14:53:51 CEST 2015

#4714: wmalossless decoder is not lossless
             Reporter:  ami_stuff    |                    Owner:
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avcodec
              Version:  git-master   |               Resolution:
             Keywords:  wmalossless  |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |

Comment (by ami_stuff):

 Replying to [comment:1 cehoyos]:
 > I tested the following:
 > {{{
 > $ mplayer test.wma -ac wma9dmo -ao pcm
 > }}}
 > The output file is shorter than FFmpeg's output (and bitexact for the
 > Is there a tool that decodes a longer file? (Is your wav file the input
 or the output file?)

 Yup, mplayer with binary codec is even worst than ffmpeg's decoder (less
 data is decoded):

 ffmpeg -i mplayer.wav/ffmpeg.wav/freac.wav -f s16le

 mplayer.pcm - 5275648 bytes
 ffmpeg.pcm - 5283840 bytes
 freac.pcm - 5294592 bytes

 so to reproduce this one would need to run "fre:ac" program under windows
 and decode
 test.wma to freac_win.wav then next:

 ffmpeg -i freac_win.wav -f s16le freac_win.pcm

 and freac_win.pcm will match:

 ffmpeg -i input.wav -f s16le input.pcm

 "input.wav" is the file I used to encode test.wma

Ticket URL: <https://trac.ffmpeg.org/ticket/4714#comment:3>
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