[FFmpeg-trac] #4829(swscale:new): Overflows (?) in xyz -> rgb conversion

[FFmpeg]

#4829: Overflows (?) in xyz -> rgb conversion
--------------------------------------+---------------------------------
               Reporter:  cehoyos     |                  Owner:
                   Type:  defect      |                 Status:  new
               Priority:  normal      |              Component:  swscale
                Version:  git-master  |               Keywords:  xyz
             Blocked By:              |               Blocking:
Reproduced by developer:  0           |  Analyzed by developer:  0
--------------------------------------+---------------------------------
 ​http://thread.gmane.org/gmane.comp.video.ffmpeg.user/58666
 The sample attached to ticket #4827 is in fact decoded fine (at least
 visually) by the native jpeg 2000 decoder but the colourspace conversion
 shows posterization artefacts.
 This is also reproducible with the libopenjpeg decoder.
 {{{
 $ ffmpeg -i frm_000127.j2c out.png
 ffmpeg version N-74866-g0cdba4a Copyright (c) 2000-2015 the FFmpeg
 developers
   built with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl
   libavutil      54. 31.100 / 54. 31.100
   libavcodec     56. 60.100 / 56. 60.100
   libavformat    56. 40.101 / 56. 40.101
   libavdevice    56.  4.100 / 56.  4.100
   libavfilter     5. 40.101 /  5. 40.101
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  2.101 /  1.  2.101
   libpostproc    53.  3.100 / 53.  3.100
 [jpeg2000 @ 0x33bd940] End mismatch 1
     Last message repeated 4 times
 [jpeg2000 @ 0x33bd940] End mismatch 2
     Last message repeated 1 times
 [jpeg2000 @ 0x33bd940] End mismatch 1
     Last message repeated 28 times
 [jpeg2000 @ 0x33bd940] End mismatch 2
 [jpeg2000 @ 0x33bd940] End mismatch 1
     Last message repeated 19 times
 Input #0, j2k_pipe, from 'frm_000127.j2c':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Video: jpeg2000 (JPEG 2000 digital cinema 2K), xyz12le,
 2048x858, 25 tbr, 25 tbn, 25 tbc
 Output #0, image2, to 'out.png':
   Metadata:
     encoder         : Lavf56.40.101
     Stream #0:0: Video: png, rgb48be, 2048x858, q=2-31, 200 kb/s, 25 fps,
 25 tbn, 25 tbc
     Metadata:
       encoder         : Lavc56.60.100 png
 Stream mapping:
   Stream #0:0 -> #0:0 (jpeg2000 (native) -> png (native))
 Press [q] to stop, [?] for help
 [jpeg2000 @ 0x3655fa0] End mismatch 1
     Last message repeated 4 times
 [jpeg2000 @ 0x3655fa0] End mismatch 2
     Last message repeated 1 times
 [jpeg2000 @ 0x3655fa0] End mismatch 1
     Last message repeated 28 times
 [jpeg2000 @ 0x3655fa0] End mismatch 2
 [jpeg2000 @ 0x3655fa0] End mismatch 1
     Last message repeated 19 times
 frame=    1 fps=0.8 q=-0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A
 video:5354kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown
 }}}
 {{{
 $ ffmpeg -vcodec libopenjpeg -pix_fmt xyz12le -i frm_000127.j2c out.png
 ffmpeg version N-74866-g0cdba4a Copyright (c) 2000-2015 the FFmpeg
 developers
   built with gcc 4.7 (SUSE Linux)
   configuration: --enable-gpl --enable-libopenjpeg
   libavutil      54. 31.100 / 54. 31.100
   libavcodec     56. 60.100 / 56. 60.100
   libavformat    56. 40.101 / 56. 40.101
   libavdevice    56.  4.100 / 56.  4.100
   libavfilter     5. 40.101 /  5. 40.101
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  2.101 /  1.  2.101
   libpostproc    53.  3.100 / 53.  3.100
 Input #0, j2k_pipe, from 'frm_000127.j2c':
   Duration: N/A, bitrate: N/A
     Stream #0:0: Video: jpeg2000, xyz12le, 2048x858, 25 tbr, 25 tbn, 25
 tbc
 Output #0, image2, to 'out.png':
   Metadata:
     encoder         : Lavf56.40.101
     Stream #0:0: Video: png, rgb48be, 2048x858, q=2-31, 200 kb/s, 25 fps,
 25 tbn, 25 tbc
     Metadata:
       encoder         : Lavc56.60.100 png
 Stream mapping:
   Stream #0:0 -> #0:0 (jpeg2000 (libopenjpeg) -> png (native))
 Press [q] to stop, [?] for help
 frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A
 video:5354kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown
 }}}
 I don't know if this ticket is related to ticket #3643.

--
Ticket URL: <https://trac.ffmpeg.org/ticket/4829>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker