[FFmpeg-trac] #9573(avcodec:new): libx264 ignores color range flag for gray10 input

[FFmpeg]

#9573: libx264 ignores color range flag for gray10 input
-------------------------------------+-------------------------------------
             Reporter:  Diederick    |                    Owner:  (none)
  Niehorster                         |
                 Type:  defect       |                   Status:  new
             Priority:  normal       |                Component:  avcodec
              Version:  git-master   |               Resolution:
             Keywords:  libx264      |               Blocked By:
  gray10                             |
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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Comment (by Diederick Niehorster):

 Since ffprobe identifies the encoded pixel format as yuv420p10le, i
 decided to see if things do look fine if that the input i provide to the
 encoder. Command:
 {{{
 ffmpeg -y -i test.mkv -vf "format=yuv420p10" -c:v libx264 -preset veryfast
 -crf 0 test.mp4
 }}}
 Then things do look fine, despite the color range flag apparently being
 lost, according to ffmpeg output:
 {{{
 Output #0, mp4, to 'test.mp4':
   Metadata:
     encoder         : Lavf59.10.100
   Stream #0:0: Video: h264 (avc1 / 0x31637661), yuv420p10le(tv,
 progressive), 1152x390, q=2-31, 500 fps, 16k tbn (default)
     Metadata:
       DURATION        : 00:00:00.018000000
       encoder         : Lavc59.15.101 libx264
 }}}

 The conversion gray10le->yuv420p10le however does not seem to be lossless
 (same when using yuv444p10le), is that expected or should i post a
 separate ticket for that?
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/9573#comment:2>
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