[FFmpeg-trac] #3409(undetermined:closed): Impossible to transcode full range RGB videos with libx264, and keep full range + proper colors

[FFmpeg]

#3409: Impossible to transcode full range RGB videos with libx264, and keep full
range + proper colors
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             Reporter:  mzso         |                    Owner:  (none)
                 Type:  defect       |                   Status:  closed
             Priority:  normal       |                Component:
                                     |  undetermined
              Version:  unspecified  |               Resolution:  invalid
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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Changes (by mirh):

 * cc: mirh (added)

Comment:

 Replying to [comment:20 Djfe]:
 > FFmpeg obviously guessed BT.709 since it's a full hd video.
 > But in fact it was BT.601

 It's not really obvious, and tbh I'd really be curious to know wherever in
 the source code this would even happen.

 Replying to [comment:21 Balling]:
 > Why this is still open? As was said many times (#8937), ffplay does not
 support it properly (this is Won't FIX) and others need to have all of the
 following

 Nobody mentioned ffplay anywhere in the thread. OP was even using MadVR,
 of all the renderers.
 Also, even if they were and nobody wanted to care about a proper fix
 (which doesn't seem like the case for instance in #8862) you'd still at
 least have the pity to put some warning here or there.

 Replying to [comment:22 Balling]:
 > The obvious problem here is that swscale defaults to YCbCr limited
 range,

 Not just that, but something in pc709.avs was changing the range and then
 forgetting about "signalling" it.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/3409#comment:23>
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