[MPlayer-users] Screenshot color wrong

[Reimar Döffinger]

On 5 September 2020 17:11:40 CEST, Polyphem <polyphem at gmail.com> wrote:
>Indeed, it does. With
>
>mplayer.exe -vo gl -vf screenshot test.mp4
>
>the max red is ~233 for this movie on screen too.
>
>But then it's wrong on screen and in PNG :)

I'm not convinced the direct3d output is right.
-vo gl has colorspace (0-3 are valid values) and levelconv (0-2 valid values) options.
If some combination gives the output you expect that might help explain it.
There is a patch on the developer mailing list that will add some additional control to the software scaler, but I don't think it will help here.

>The auto-selected direct3d vo driver does seem to perform the correct 
>color un-uncompression ("automagically"?) I want on PNG too.

Or it creates exaggerated colours on purpose to "look better"? As it's the graphics driver that decides what it looks like.
You can always add filters to change brightness, contrast, saturation and gamma.
Or use a screenshot program that actually captures the screen. In a way, the screenshot filter is kind of a relic from a time where taking such screenshots of a video would only show a green square, but that's not an issue anymore.