On Thu, Mar 03, 2022 at 02:06:45PM +0200, Martin Storsjö wrote:
> While swscale can be reconfigured with sws_setColorspaceDetails,
> the in/out ranges also need to be set before calling
> sws_init_context, otherwise the initialization might choose
> fastpaths that don't take the ranges into account.
> 
> Therefore, look at in->color_range too, when deciding on whether
> the scaler needs to be reconfigured.
> 
> Add a new member variable for keeping track of this, for being
> able to differentiate between whether the scale filter parameter
> "in_range" has been set (which should override whatever the input
> frame has set) or whether it has been configured based on the
> latest frame (which should trigger reconfiguring the scaler if
> the input frame ranges change).
> 
> Signed-off-by: Martin Storsjö <martin@martin.st>
> ---
> To test this (without risking running many conflicting swscale
> filters in one filter pipeline), we'd need to be able to tag
> the incoming raw yuv data with colorspace and range without setting
> the in_color_matrix and in_range options on the scale filter.
> 
> When using the rawvideo demuxer, the pixel format is set via the
> ffmpeg -pix_fmt option, but there's no corresponding option for
> setting color matrix or range for it.
> ---
>  libavfilter/vf_scale.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)

This changes the output for:
ffmpeg -i tickets/524/AVCI50.mov   -vframes 3 file-avci50dec.nut
ffmpeg -i tickets/4493/AVCI100.mov -vframes 3 file-avci100dec.nut

https://samples.ffmpeg.org/ffmpeg-bugs/trac/ticket524/

Is that intended ?

- 233903 file-avci100dec.nut
- 383853 file-avci50dec.nut
+ 196558 file-avci100dec.nut
+ 333893 file-avci50dec.nut

thx

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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