Opened 22 months ago
Last modified 7 weeks ago
#10123 new defect
j2k decoder fails on on conformance codestream p0_09.j2k when bitexact is used
Reported by: | Pierre-Anthony Lemieux | Owned by: | |
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Priority: | minor | Component: | avcodec |
Version: | git-master | Keywords: | j2k |
Cc: | MasterQuestionable | Blocked By: | |
Blocking: | Reproduced by developer: | no | |
Analyzed by developer: | no |
Description
The jpeg2000 decoder fails to accurately decode the p0_09.j2k image from the ISO/ITU conformance codestream set when bitexact is set.
Compare:
ffmpeg -i p0_09.j2k p0_09.png
and
ffmpeg -flags +bitexact -i p0_09.j2k p0_09.exact.png
with the reference image (attached) generated from c1p0_09-0.pgx.
Attachments (1)
Change History (6)
by , 22 months ago
Attachment: | jpeg2000-p0_09.src.png added |
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comment:1 by , 22 months ago
comment:2 by , 22 months ago
It is not an HTJ2K codestream. Description at https://gitlab.com/wg1/htj2k-codestreams/-/blob/master/descriptions_profile0/p0_09syntax.txt
comment:3 by , 22 months ago
Why are using bitexact here?
Interesting,
by decoding to .yuv (rawvideo (Y800 / 0x30303859), gray(progressive)) you can indeed see it is different with +bitexact. Ha
On the other hand this sample is lossy...
comment:4 by , 5 months ago
Cc: | added |
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͏ https://trac.ffmpeg.org/wiki/colorspace#bitexact
͏ .
͏ Take care the "stochastic" part.
͏ Does JPEG 2000 use such technique? and for decoding..?
͏ Sounds unpractical.
Is that HTJ2K codestream too?