kam@dlogics.UUCP (Kevin Mitchell) (11/29/89)
I'm using a Floyd-Steinburg dither to reduce the number of colors in an image. To find the colors I need quickly, I'm using an inverse table- a three-dimensional array indexed by color value yielding the color index to put into the image. Right now, I'm comparing each color position in the inverse table to each color in the color lookup table to find the index I want. Since I'm using the Pythagorean Theorem to find the distance, I'm executing thousands of multiplications and it takes a long time (Macintosh Plus; 68000 at 8Mhz). I must be missing something obvious, since I know that there are fast implementations out there; such as in Apple's color QuickDraw software. Please reply if you have any comments on: o Fast ways of stuffing inverse color tables. o Better ways of converting colors to color indices. Thanks. -- Kevin A. Mitchell (312) 266-4485 Datalogics, Inc Internet: kam@dlogics.UUCP 441 W. Huron UUCP: ..!uunet!dlogics!kam Chicago, IL 60610 FAX: (312) 266-4473