Re: reversable, but not 1D color transforms in config.ocio


Doesn't really answer your question (sorry) but.... On Transformers the director wanted sharper cg robots! so we had a sharpen shootout. The joint winners were either LAB or Log, unshapen masks.i.e. the difference between artifacts when filtering it in L*AB or log was very minimal.  It might be easier for your PS artists to use a lut rather than a RGB>LAB transform?

On Sunday, 5 February 2017 06:13:36 UTC, Troy James Sobotka wrote:
Whilst stranded in an airport...

No assurances expressed or implied. Seems the values are darn close to Lindbloom's, which may account for a different value for Illuminant C adaptation via Bradford.

With respect,

On Sat, Feb 4, 2017 at 11:58 AM doug <col...@...> wrote:
The conversion from XYZ to CIELab can be done with matrices and 1d-LUTs, so you should be able to do the forward and reverse quite exactly with the existing machinery and without resorting to 3d-LUTs.

(Of course CIELab is only appropriate for display-referred colors, but that is a separate issue.)

Doug Walker

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