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I try to create a profile from measurement that can be used by MPV. The problem is that only the gamut gets corrected, but gamma not. When I create a synthetic profile and use extreme gamma values I can see that MPV is basically able to correct gamma from an ICC profile. Only the one created from measurement doesn’t work correctly. I also tried LUT + Matrix and only LUT. No difference.
When I create 3D LUTs (e.g. cube or 3dlut) it works fine in madVR and dwm_lut. I verified everything with CalMAN. With grey scale and saturation sweeps I can see if it works or not. Sadly MPV doesn’t support 3D LUTs. Instead it creates its own from ICC profile.
Andy ideas why the measures ICC profile doesn’t correct gamma in MPV?
Thank you.
Andy ideas why the measures ICC profile doesn’t correct gamma in MPV?
Because you are not saying to MPV that source colorspace is gamma X.X. It works as intened. It can be 2.2, 2.4… and it shoudl be available in mpv config params
Because you are not saying to MPV that source colorspace is gamma X.X. It works as intened. It can be 2.2, 2.4… and it shoudl be available in mpv config params
I don’t understand what you mean. The source EOTF of the file is determined by the player. The ICC profile contains the target transfer function of the display and that should be used for output. What exactly should I tell MPV?
I still don’t get it. There are two parameters for gamma in MPV. One is for input (which is automatically detected) and the other is for target (target-trc=gamma2.2). The first one doesn’t change anything if set manually. The second one is ignored when ICC profile is used as stated in the manual:
–target-trc=<value>
Specifies the transfer characteristics (gamma) of the display. Video colors will be adjusted to this curve when ICC color management is not being used.
The weird thing is that synthetic profiles work. I can clearly see and measure the difference in gamut and gamma. Only measured profiles don’t work correctly regarding gamma. Where is the difference?
The weird thing is that synthetic profiles work. I can clearly see and measure the difference in gamut and gamma. Only measured profiles don’t work correctly regarding gamma. Where is the difference?
Because using a synth fake profile then display profile (synth) and display do not match, hence you are breaking the whole chain.
You shoudl do what you do when creating a LUT3D. Destination profile is display profile with whatever TRC you aimed to (it dioes not matter color managed).
In source profile fro a LUT3D you aim for a “reference content colorspace”. That includes if simulated gamut will be g2.2 or g2.4. In an ICC compatible player you should specify if you wish a different source TRC than default.https://mpv.io/manual/master/#video-filters
It seems that parameter is “gamma” but I do not use mpv. Default settings on a limited contrast 1000:1 display should look close to sRGB/2.2 with lighter dark greys.
