On Mon, Nov 23, 2015 at 1:44 AM, Caio S. Souza <caiobio...@gmail.com> wrote: > Hello, > To preserve luminosity when using the Channel Mixer module one must be > careful in choosing values for the red, green and blue sliders such that > their sum equals 1. If we need to change the sliders values a lot (e.g. when > experimenting with their importance on a black and white conversion), it > becomes very slow and painfull to drag all others sliders appropriately to > keep the overall luminosity. Mainly when you use differents values for > different parts of a single image. It would be much faster and easier to > have an option to keep the image luminosity, like in Gimp's channel mixer > (https://docs.gimp.org/en/plug-in-colors-channel-mixer.html). This is > relatively easy to implement: we just need to divide the computed value by > the sum of the three chosen weights. > I took a look at this module's source code and identified the pieces that > must be changed (including the opencl kernel). If you agree this feature is > a good idea, I may help implementing it. What do you think? >
0. html mail is bad :) 1. some blending operator is the solution here, i believe. have you tried, e.g. color/Lab color/HSV color ? > Cheers > -- > Caio S. Souza Roman. > Laboratório de Biologia Teórica e Computacional > Universidade de Brasília > www.lbtc.unb.br > > ___________________________________________________________________________ > darktable developer mailing list to unsubscribe send a mail to > darktable-dev+unsubscr...@lists.darktable.org ___________________________________________________________________________ darktable developer mailing list to unsubscribe send a mail to darktable-dev+unsubscr...@lists.darktable.org
