Hi David ;), > This is a normal phenomenon when moving to higher bitdepths. > Unless you're talking about 16 bits in total, and not 16 bits per > channel, in which case I'd be a bit mystified... Yes, i meant 16 bits per channel ;) > Floyd-Steinberg dithering is basically a way to approximate more > colors with a smaller palette... it does not actually do anything > like what you are expecting (as you have noticed). Yup, i already noticed that. Maybe i'm wrong, so please correct me, but the Floyd-Steinberg is implemented by the gimp, and the dithering in gdk_pixbuf (the paramater XlibRgbDither to functions like gdk_pixbuf_draw) are different things, isn't it? > Have you tried blurring the image with a radius of 0.5 or 1.5 > pixels? This sometimes works quite well. I've tried it without success. The bands are too visible to be removed with a blur filter... > > Programs like gqview, an image viewer, use the dither > > algorithms bundled with gdx_pixbuf in gtk2, and they work perfectly with > > the same images. Why cannot the gimp do the same quality dithering if > > it's using the same library? > > Oh, I see what you mean, I think - you're talking about the > rendering of the data, you don't actually want to change the > underlying data, you want it to look better. Is that right? Yes, i want it to look better, and have the option to save the dithered image ;). Gqview does a dithering pass on the image, and the image looks great. I looked in the sources and saw that it doesn't implements any dithering algorithm, it just uses the underlying gdk_pixbuf dithering support. > If that's the case, then I'm afraid the answer is that I don't > know. I thought we used a GdkPixbuf, so if we don't I'm stumped > :) I know that the Gimp is using GdkPixbuf, that's why i'm asking why it doesn't do a better dithering ;) cheers, -- David Gómez "The question of whether computers can think is just like the question of whether submarines can swim." -- Edsger W. Dijkstra
