Create synthetic ICC with VCGT

[Hansebenger]

Hi,

I have discovered the tool “create synthetic ICC profile”. Unfortunately it doesn’t create a vcgt tag, so Windows doesn’t load it. I want to only tune 1D gamma ramps, so vcgt would be perfectly suitable. Is there a way to convert the output to vcgt?

[Vincent]

Displaycal Curve viewer, dump current VCGT to .cal. Or use that/another .cal as a sample and put your own numbers with same format. Then use some command line argyll tool to append that .cal to synth ICC. I do not remember name, look on documentation, maybe “applycal”.

• This reply was modified 3 years, 2 months ago by Vincent.

[Hansebenger]

You are right, it is called applycal: https://www.argyllcms.com/doc/applycal.html

But forget my question, I have found a way to directly hack vcgt:

I have taken an ICC profile with some embedded vcgt calibration: http://fotovideotec.de/farbmanagement/downloads/testkalibrierung_blaeulich.icm.
With https://github.com/KennethEvans/colormanagement I could reverse engineer pretty quickly this particular vgct’s function and hack a desired one into it with a hex editor.

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