[FFmpeg-trac] #10973(undetermined:new): scale2ref truncates the referent stream

[FFmpeg]

#10973: scale2ref truncates the referent stream
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             Reporter:  boris-       |                    Owner:  (none)
  petrov                             |
                 Type:  defect       |                   Status:  new
             Priority:  important    |                Component:
                                     |  undetermined
              Version:  git-master   |               Resolution:
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
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Comment (by maruno):

 I came across this issue as well after upgrading to ffmpeg 7.0.

 What I noticed as well researching the issue is that the `scale2ref` was
 not as-is in the documentation anymore. It seems it's being integrated
 into the normal `scale` filter and the documentation was already reflected
 to this situation.

 It doesn't work in the 7.0-release version, bug I installed the latest
 HEAD (8670615743eb36d7b3e9b522266518796df7ec54) version and changed my
 parameters to reflect the new `scale` filter syntax that performs the
 reference:

 From: `[1:v][scaled_v]scale2ref=w=oh*mdar:h=ih/1.25[scaled_wm][scaled_v]`

 To:
 `[scaled_v]split[ref][scaled_v];[1:v][ref]scale=w=oh*dar:h=rh/1.25[scaled_wm]`

 The new syntax is a bit weird with the required split in front, but it
 worked! (I suspect the documentation or implementation might not be final)
 The bug doesn't occur with this HEAD-build and the new `scale`-filter
 syntax with reference. Perhaps this helps you.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10973#comment:1>
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