In that thread, I meant the tiny amount of dither that is sometimes added when converting floating point to integer data, usually the magnitude of the dither is just +/- 1/2 quantization unit, right before the conversion to integer. We never tackled that, and as far as I know, nobody has really brought it up since then (despite pretty widespread use of the tools), so I'm assuming it's not a pressing issue.
For a format like GIF where the only supported output format is an indexed color map, I would certainly expect the plugin to handle the selection of color map and dithering to try to make a continuous image look as good as possible under those constraints. On Oct 13, 2013, at 7:42 AM, Mariusz Szczepańczyk wrote: > Hi, > > I am the author of a read support for GIF images and at last found some time > to get down to writing an output plugin. > > As far as I know the GIF specification enforces the usage of an indexed color > map limited to 256 colors. So to do any sensible conversion from high > resolution source image, some kind of color quantization and dithering is > needed. I did a little lookup and found this thread from 2010: > http://lists.openimageio.org/pipermail/oiio-dev-openimageio.org/2010-December/003687.html > > Larry, you raised the issue that dithering shouldn't be implemented by an > individual plugin and how should it be exactly done is a matter to think > over. What is the current status of the subject? Have you had any thoughts > how should it be resolved? > > Regards, > Mariusz > -- Larry Gritz [email protected] _______________________________________________ Oiio-dev mailing list [email protected] http://lists.openimageio.org/listinfo.cgi/oiio-dev-openimageio.org
