Re: [Gimp-developer] the indexed mode implementation

[Mukund Sivaraman <muks banu com>]

Hi Ashi

On Sun, Apr 08, 2012 at 10:18:48PM +0800, 阿四 wrote:
> Hi,all.
> I'm curious about how the indexed mode in gimp is implemented. Because I
> implemented a function which change a RGB colorspace image to indexed color
> image before, but my implementation is extremely slow. The algorithm is
> trivial, the runtime is about O(n^k), where n is number of pixels, k is the
> size of index. However, I tried indexed mode in GIMP on same image on same
> computer, it's really faster than my implementation.
> Could anyone give me some information about the indexed mode in GIMP?

See this article (and the linked articles from there). Floyd Steinberg
is very simple to implement and has a linear runtime:

http://en.wikipedia.org/wiki/Floyd%E2%80%93Steinberg_dithering


Kind regards,

Mukund