People working out of OIIO master, please be aware of some changes from PR #1864 that I just merged, that are related to OCIO color transformations:
* ImageBufAlgo::colorconvert() and the various ocio_etc() functions have had the default value of their optional parameter 'unpremult' changed from false to true. Also, pertaining to oiiotool: * oiiotool --colorconvert (and --ocio_etc) take an optional modifier, --colorconvert:unpremult=1 which causes the color transformation to be bracketed by an unpremult/premult pair internally. The default currently is =0, but we anticipate that in a later change we will set the default to 1. * Explicit --unpremult now more clearly marks its output metadata as unpremultiplied, and you will get a warning from oiiotool if you do both --unpremult and specific unpremult=1 modifier to the color conversion. * oiiotool --autocc now properly does an internal unpremult/premult when it does any color transformations. Previously, it did not, which I now think was incorrect. I would strongly recommend using --colorconvert:unpremult=1 rather than an explicit --unpremult before and --premult after the color conversion (which is much more error prone -- it's easy to leave one out, or to accidentally edit the command line to have other operations inappropriately between them). If your pipeline is one where your image filenames always embed OCIO color space names (e.g., foo_lnh.0001.exr or foo_vd16.0001.jpg), then I recommend using --autocc on your oiiotool command lines to automatically transform to linear space upon input and back to the named space upon output, rather than have explicit --colorconvert commands that merely do the same input->output transformations by hand. -- Larry Gritz l...@larrygritz.com _______________________________________________ Oiio-dev mailing list Oiio-dev@lists.openimageio.org http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org