I think the earlier suggestion I gave about the contrast amount taking either a float (applied to all channels) or a per-channel comma-separated list of values will be sufficient. --contrast 1.5,1.5,1.5,1,1 would scale R, G, B, but not A or Z, for example (in an RGBAZ image).
That is, we don't need a "channel mask" as long as we have a way to specify per-channel contrast adjustment, since "1.0" is the same thing as "don't modify this channel." On Jul 25, 2012, at 2:52 PM, Stefan Stavrev wrote: > Nice detail catch there, yes lum=1 would be better. > > What if we want to modify the Z channel too? > Or modify Z and alpha, or alpha only but not Z? > It does make sense to modify contrast for alpha and Z. > > I see two options: > > 1. Channels masks. > > 2. Lots of assumptions and usage limitations. -- Larry Gritz [email protected] _______________________________________________ Oiio-dev mailing list [email protected] http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org
