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ggarra13 / mrv2

Professional player and review tool for vfx, animation and computer graphics.
https://mrv2.sourceforge.io
BSD 3-Clause "New" or "Revised" License
222 stars 14 forks source link

OCIO Output Transforms? #146

Closed melMass closed 9 months ago

melMass commented 1 year ago

Hi,

Thanks for mrv2, I stumble on this project yesterday while looking for alternative sequence players and I really like it. I kinda share the points from #132 but not a big deal. One thing I don't understand is how (if possible) to specify an OCIO output transform when rendering to a video file?

I'm not entirely sure of the current behaviour

Thanks

ggarra13 commented 1 year ago

Currently, you cannot specify an OCIO output transform (in Nuke's way of doing it).

You can set your custom config.ocio file in the Preferences->OCIO (F10). Then that will allow you to select the Input Color Space transform as well as the Display/View transform in the main pull downs of the UI. When saving a movie file, both transforms are applied to give you a WYIWYG.

melMass commented 12 months ago

both transforms are applied to give you a WYIWYG.

I don't think this is true unfortunately, I naively though so at first but posted the issue after comparing the outputs. I will try to get a proper repro with a ground truth

ggarra13 commented 12 months ago

If you are comparing an EXR to a Movie file with the color pipeline, you are likely going to not get a perfect match. When going to a movie file, you loose precision due to:

However, if you stay in float or half (by reading and saving exrs after going through the pipeline), you should not see visible color differences.

Anyway, if you have an example where this does not hold true, post it here and I'll take a look at it.

ggarra13 commented 10 months ago

@melMass Were you able to find the problem or get a sample test case? I am going through the list of bugs before I hit v1.0.0.