This feature (use LUT file without change OCIO config) available via OCIO::FileTransform, but is not yet available in blender CAPI interface.
Please, see this thread in bf-compositor list: http://lists.blender.org/pipermail/bf-compositor/2013-November/000027.html And tail of this http://wiki.blender.org/index.php/Dev:Ref/Proposals/Compositor Apply LUT node currently has the following problems: 1) Using OCIO directly, without blender CAPI. 2) Ignores that blender internally use linear color space, but LUT profiles mainly required srgb. 2014/1/25 Björn Sonnenschein <gr...@unitybox.de> > Hello, > Is there a way to check the luts folder/the ocio config file for changes > while runtime? > > The background is that I would like to write an lut node for the > compositor that allows to apply lookup tables via ocio conversion like > color grading applications like Davinci Resolve do. The purpose is to be > able to bake color grading setups into a simple 3d lut that may be > applied in other projects and shared with other users easily. In > contrast to the film response curves blender provides for the final > color space transformation, an lut node makes it possible to use luts in > every position of the grading workflow. For Example I may use premade > luts for my Blackmagic camera to get a good starting point for further > grading work. > > I have already written a proof-of-concept 3D lut editor addon for > blender. > > http://blenderartists.org/forum/showthread.php?322805-Compositor-Addon-3D-LUT-Editor > It sets up a 3d scene with a 3d lut cube whick can be manipulated and > then creates a rudimentary node tree that uses the position values of > the spheres in the lut for calculating the new picture. > Now, the real purpose of the script would be to parse a new lut file > into the ocio folder with the corresponding values of the created 3d lut > and also make the entry into the ocio config file and then, if you > manipulate the the 3d lut in blender, update the lut file and then make > ocio update the luts it has loaded so that you can get a realtime > preview of what you do using the compositor with the lut node. > > My plan to realize the update of the lut cache would be to implement a > function to do this into the lut node which may be accessed by the user > to update the lut list if he has added a downloaded lut to the folder > and also by the python api so that the script may call it. > > By the way, does anyone know how to work with .cube luts coming from > davinci resolve in ocio properly and in which color space they have to > be applied? I have tried this one > http://www.captainhook.co.nz/blackmagic-cinema-camera-lut/ > by creating a new pseudo color space which interprets the input image as > sRGB, converts it into Blender´s Linear space and then applies the lut, > but this does not create the right results (You may simply try it out > with the image pairs on the website if you like). > > Kind regards, > Björn Sonnenschein > > > _______________________________________________ > Bf-committers mailing list > Bf-committers@blender.org > http://lists.blender.org/mailman/listinfo/bf-committers > _______________________________________________ Bf-committers mailing list Bf-committers@blender.org http://lists.blender.org/mailman/listinfo/bf-committers