[FFmpeg-trac] #4653(avcodec:open): jpeg2000: -M 1 mode is not lossless (compared to openjpeg)

[FFmpeg]

#4653: jpeg2000: -M 1 mode is not lossless (compared to openjpeg)
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             Reporter:  ami_stuff   |                    Owner:
                 Type:  defect      |                   Status:  open
             Priority:  normal      |                Component:  avcodec
              Version:  git-master  |               Resolution:
             Keywords:  j2k         |               Blocked By:
             Blocking:              |  Reproduced by developer:  1
Analyzed by developer:  0           |
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Comment (by ami_stuff):

 After re-testing it looks like output of -M 2/8/16/32-encoded files
 decoded by openjpeg is identical to input bmp image (and to the output
 from ffmpeg's decoder), while output of -M 1/4-encoded files is not the
 same, so maybe there is no bug?

 What I notice is that output of "lossless_m1.jp2​" looks better from
 openjpeg's decoder than from ffmpeg's decoder.

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Ticket URL: <https://trac.ffmpeg.org/ticket/4653#comment:3>
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