nolan@tut.cis.ohio-state.edu (Michael C Nolan) (06/10/89)
Does anybody know where I can find (or how to generate) 8 by 8 and 16 by 16 dither patterns? Thanks. -Mike nolan@hiips.lpl.arizona.edu; ...!noao!solpl!hiips
pokey@well.UUCP (Jef Poskanzer) (06/11/89)
In the referenced message, Michael C Nolan <nolan@cis.ohio-state.edu> wrote: }Does anybody know where I can find (or how to generate) 8 by 8 and }16 by 16 dither patterns? (comp.graphics is a pretty good place to ask this question. Must be, since it gets asked there so often.) /* ** dithers.h ** ** Here are some dithering matrices. They are all taken from "Digital ** Halftoning" by Robert Ulichney, MIT Press, ISBN 0-262-21009-6. */ /* ** Order-6 ordered dithering matrix. Note that smaller ordered dithers ** have no advantage over larger ones, so use dither8 instead. */ static int dither6[8][8] = { 1, 59, 15, 55, 2, 56, 12, 52, 33, 17, 47, 31, 34, 18, 44, 28, 9, 49, 5, 63, 10, 50, 6, 60, 41, 25, 37, 21, 42, 26, 38, 22, 3, 57, 13, 53, 0, 58, 14, 54, 35, 19, 45, 29, 32, 16, 46, 30, 11, 51, 7, 61, 8, 48, 4, 62, 43, 27, 39, 23, 40, 24, 36, 20 }; /* Order-8 ordered dithering matrix. */ static int dither8[16][16] = { 1,235, 59,219, 15,231, 55,215, 2,232, 56,216, 12,228, 52,212, 129, 65,187,123,143, 79,183,119,130, 66,184,120,140, 76,180,116, 33,193, 17,251, 47,207, 31,247, 34,194, 18,248, 44,204, 28,244, 161, 97,145, 81,175,111,159, 95,162, 98,146, 82,172,108,156, 92, 9,225, 49,209, 5,239, 63,223, 10,226, 50,210, 6,236, 60,220, 137, 73,177,113,133, 69,191,127,138, 74,178,114,134, 70,188,124, 41,201, 25,241, 37,197, 21,255, 42,202, 26,242, 38,198, 22,252, 169,105,153, 89,165,101,149, 85,170,106,154, 90,166,102,150, 86, 3,233, 57,217, 13,229, 53,213, 0,234, 58,218, 14,230, 54,214, 131, 67,185,121,141, 77,181,117,128, 64,186,122,142, 78,182,118, 35,195, 19,249, 45,205, 29,245, 32,192, 16,250, 46,206, 30,246, 163, 99,147, 83,173,109,157, 93,160, 96,144, 80,174,110,158, 94, 11,227, 51,211, 7,237, 61,221, 8,224, 48,208, 4,238, 62,222, 139, 75,179,115,135, 71,189,125,136, 72,176,112,132, 68,190,126, 43,203, 27,243, 39,199, 23,253, 40,200, 24,240, 36,196, 20,254, 171,107,155, 91,167,103,151, 87,168,104,152, 88,164,100,148, 84 }; /* Order-3 clustered dithering matrix. */ static int cluster3[6][6] = { 9,11,10, 8, 6, 7, 12,17,16, 5, 0, 1, 13,14,15, 4, 3, 2, 8, 6, 7, 9,11,10, 5, 0, 1,12,17,16, 4, 3, 2,13,14,15 }; /* Order-4 clustered dithering matrix. */ static int cluster4[8][8] = { 18,20,19,16,13,11,12,15, 27,28,29,22, 4, 3, 2, 9, 26,31,30,21, 5, 0, 1,10, 23,25,24,17, 8, 6, 7,14, 13,11,12,15,18,20,19,16, 4, 3, 2, 9,27,28,29,22, 5, 0, 1,10,26,31,30,21, 8, 6, 7,14,23,25,24,17 }; /* Order-8 clustered dithering matrix. */ static int cluster8[16][16] = { 64, 69, 77, 87, 86, 76, 68, 67, 63, 58, 50, 40, 41, 51, 59, 60, 70, 94,100,109,108, 99, 93, 75, 57, 33, 27, 18, 19, 28, 34, 52, 78,101,114,116,115,112, 98, 83, 49, 26, 13, 11, 12, 15, 29, 44, 88,110,123,124,125,118,107, 85, 39, 17, 4, 3, 2, 9, 20, 42, 89,111,122,127,126,117,106, 84, 38, 16, 5, 0, 1, 10, 21, 43, 79,102,119,121,120,113, 97, 82, 48, 25, 8, 6, 7, 14, 30, 45, 71, 95,103,104,105, 96, 92, 74, 56, 32, 24, 23, 22, 31, 35, 53, 65, 72, 80, 90, 91, 81, 73, 66, 62, 55, 47, 37, 36, 46, 54, 61, 63, 58, 50, 40, 41, 51, 59, 60, 64, 69, 77, 87, 86, 76, 68, 67, 57, 33, 27, 18, 19, 28, 34, 52, 70, 94,100,109,108, 99, 93, 75, 49, 26, 13, 11, 12, 15, 29, 44, 78,101,114,116,115,112, 98, 83, 39, 17, 4, 3, 2, 9, 20, 42, 88,110,123,124,125,118,107, 85, 38, 16, 5, 0, 1, 10, 21, 43, 89,111,122,127,126,117,106, 84, 48, 25, 8, 6, 7, 14, 30, 45, 79,102,119,121,120,113, 97, 82, 56, 32, 24, 23, 22, 31, 35, 53, 71, 95,103,104,105, 96, 92, 74, 62, 55, 47, 37, 36, 46, 54, 61, 65, 72, 80, 90, 91, 81, 73, 66 };