[FFmpeg-trac] #225(swscale:reopened): Converting from YUVJ to YUV lose contrast

[FFmpeg]

#225: Converting from YUVJ to YUV lose contrast
-------------------------------------+-------------------------------------
             Reporter:  sghpunk      |                    Owner:
                 Type:  defect       |                   Status:  reopened
             Priority:  normal       |                Component:  swscale
              Version:  git-master   |               Resolution:
             Keywords:  YUV/YUVJ     |               Blocked By:
  contrast                           |  Reproduced by developer:  0
             Blocking:               |
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------

Comment (by mantler):

 I arrived at this thread because I'm trying to figure out the correct
 AVColorRange for AV_PIX_FMT_YUVJ*P formats.  The handle_jpeg method in
 libswscale/utils.c uses 1 (corresponding to AVCOL_RANGE_MPEG) when
 changing yuvj to yuv, and I'm wondering if it should instead use
 AVCOL_RANGE_JPEG?  AVCOL_RANGE_MPEG is a compressed range compared to
 AVCOL_RANGE_JPEG, and I suspect this is what is causing the contrast
 issues you're referring to?

--
Ticket URL: <https://trac.ffmpeg.org/ticket/225#comment:24>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker