/* * gray.c -- * *      More procedures to dither grey-scale images. * *//* * Copyright (c) 1995 The Regents of the University of California. * All rights reserved. *  * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose, without fee, and without written agreement is * hereby granted, provided that the above copyright notice and the following * two paragraphs appear in all copies of this software. *  * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *  * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. */#include "video.h"#include "proto.h"#include "dither.h"/* *-------------------------------------------------------------- * * GrayDitherImage -- * *	Dithers image into 128 gray scales. Simply maps luminance *      value into 1 of 128 gray scale colors (divide by two, essentially). * * Results: *	None. * * Side effects: *	None. * *-------------------------------------------------------------- */voidGrayDitherImage(lum, cr, cb, out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *out;    int w, h;{  int i, max = w*h/16;  for (i=0; i<max; i++) {    out[0] = pixel[lum[0]];    out[1] = pixel[lum[1]];    out[2] = pixel[lum[2]];    out[3] = pixel[lum[3]];    out[4] = pixel[lum[4]];    out[5] = pixel[lum[5]];    out[6] = pixel[lum[6]];    out[7] = pixel[lum[7]];    out[8] = pixel[lum[8]];    out[9] = pixel[lum[9]];    out[10] = pixel[lum[10]];    out[11] = pixel[lum[11]];    out[12] = pixel[lum[12]];    out[13] = pixel[lum[13]];    out[14] = pixel[lum[14]];    out[15] = pixel[lum[15]];    out += 16;    lum += 16;  }}voidGray16DitherImage(lum, cr, cb, p_out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *p_out;    int w, h;{  unsigned short *out = (unsigned short *)p_out;  int i, max = w*h/16;  for (i=0; i<max; i++) {    out[0] = wpixel[lum[0]];    out[1] = wpixel[lum[1]];    out[2] = wpixel[lum[2]];    out[3] = wpixel[lum[3]];    out[4] = wpixel[lum[4]];    out[5] = wpixel[lum[5]];    out[6] = wpixel[lum[6]];    out[7] = wpixel[lum[7]];    out[8] = wpixel[lum[8]];    out[9] = wpixel[lum[9]];    out[10] = wpixel[lum[10]];    out[11] = wpixel[lum[11]];    out[12] = wpixel[lum[12]];    out[13] = wpixel[lum[13]];    out[14] = wpixel[lum[14]];    out[15] = wpixel[lum[15]];    out += 16;    lum += 16;  }}voidGray32DitherImage(lum, cr, cb, p_out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *p_out;    int w, h;{  unsigned int *out = (unsigned int *)p_out;  int i, max = w*h/16;  for (i=0; i<max; i++) {    out[0] = wpixel[lum[0]];    out[1] = wpixel[lum[1]];    out[2] = wpixel[lum[2]];    out[3] = wpixel[lum[3]];    out[4] = wpixel[lum[4]];    out[5] = wpixel[lum[5]];    out[6] = wpixel[lum[6]];    out[7] = wpixel[lum[7]];    out[8] = wpixel[lum[8]];    out[9] = wpixel[lum[9]];    out[10] = wpixel[lum[10]];    out[11] = wpixel[lum[11]];    out[12] = wpixel[lum[12]];    out[13] = wpixel[lum[13]];    out[14] = wpixel[lum[14]];    out[15] = wpixel[lum[15]];    out += 16;    lum += 16;  }}/* *-------------------------------------------------------------- * * Gray2DitherImage -- * *	Dithers image into 128 gray scales. Simply maps luminance *      value into 1 of 128 gray scale colors (divide by two, essentially). * * Results: *	None. * * Side effects: *	None. * *-------------------------------------------------------------- */voidGray2DitherImage(lum, cr, cb, p_out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *p_out;    int w, h;{  int x, y;  unsigned short *out = (unsigned short *)p_out;  unsigned short *out2 = out + w;  for (y=0; y<h; y++) {    for (x=0; x<w; x+=16) {      out[0] = out2[0] = wpixel[lum[0]];      out[1] = out2[1] = wpixel[lum[1]];      out[2] = out2[2] = wpixel[lum[2]];      out[3] = out2[3] = wpixel[lum[3]];      out[4] = out2[4] = wpixel[lum[4]];      out[5] = out2[5] = wpixel[lum[5]];      out[6] = out2[6] = wpixel[lum[6]];      out[7] = out2[7] = wpixel[lum[7]];      out[8] = out2[8] = wpixel[lum[8]];      out[9] = out2[9] = wpixel[lum[9]];      out[10] = out2[10] = wpixel[lum[10]];      out[11] = out2[11] = wpixel[lum[11]];      out[12] = out2[12] = wpixel[lum[12]];      out[13] = out2[13] = wpixel[lum[13]];      out[14] = out2[14] = wpixel[lum[14]];      out[15] = out2[15] = wpixel[lum[15]];      out += 16;      out2 += 16;      lum += 16;    }  out += w;  out2 += w;  }}voidGray216DitherImage(lum, cr, cb, p_out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *p_out;    int w, h;{  int x, y;  unsigned int *out = (unsigned int *)p_out;  unsigned int *out2 = out + w;  for (y=0; y<h; y++) {    for (x=0; x<w; x+=16) {      out[0] = out2[0] = wpixel[lum[0]];      out[1] = out2[1] = wpixel[lum[1]];      out[2] = out2[2] = wpixel[lum[2]];      out[3] = out2[3] = wpixel[lum[3]];      out[4] = out2[4] = wpixel[lum[4]];      out[5] = out2[5] = wpixel[lum[5]];      out[6] = out2[6] = wpixel[lum[6]];      out[7] = out2[7] = wpixel[lum[7]];      out[8] = out2[8] = wpixel[lum[8]];      out[9] = out2[9] = wpixel[lum[9]];      out[10] = out2[10] = wpixel[lum[10]];      out[11] = out2[11] = wpixel[lum[11]];      out[12] = out2[12] = wpixel[lum[12]];      out[13] = out2[13] = wpixel[lum[13]];      out[14] = out2[14] = wpixel[lum[14]];      out[15] = out2[15] = wpixel[lum[15]];      out += 16;      out2 += 16;      lum += 16;    }  out += w;  out2 += w;  }}#ifndef SIXTYFOUR_BITvoidGray232DitherImage(lum, cr, cb, p_out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *p_out;    int w, h;{  int x, y;  unsigned int *out = (unsigned int *)p_out;  unsigned int *out2 = out + w * 2;  for (y=0; y<h; y++) {    for (x=0; x<w; x+=16) {      out[0] = out2[0] = out[1] = out2[1] = wpixel[lum[0]];      out[2] = out2[2] = out[3] = out2[3] = wpixel[lum[1]];      out[4] = out2[4] = out[5] = out2[5] = wpixel[lum[2]];      out[6] = out2[6] = out[7] = out2[7] = wpixel[lum[3]];      out[8] = out2[8] = out[9] = out2[9] = wpixel[lum[4]];      out[10] = out2[10] = out[11] = out2[11] = wpixel[lum[5]];      out[12] = out2[12] = out[13] = out2[13] = wpixel[lum[6]];      out[14] = out2[14] = out[15] = out2[15] = wpixel[lum[7]];      out[16] = out2[16] = out[17] = out2[17] = wpixel[lum[8]];      out[18] = out2[18] = out[19] = out2[19] = wpixel[lum[9]];      out[20] = out2[20] = out[21] = out2[21] = wpixel[lum[10]];      out[22] = out2[22] = out[23] = out2[23] = wpixel[lum[11]];      out[24] = out2[24] = out[25] = out2[25] = wpixel[lum[12]];      out[26] = out2[26] = out[27] = out2[27] = wpixel[lum[13]];      out[28] = out2[28] = out[29] = out2[29] = wpixel[lum[14]];      out[30] = out2[30] = out[31] = out2[31] = wpixel[lum[15]];      out += 32;      out2 += 32;      lum += 16;    }  out += w * 2;  out2 += w * 2;  }}#else /* def SIXTYFOUR_BIT */voidGray232DitherImage(lum, cr, cb, p_out, h, w)    unsigned char *lum;    unsigned char *cr;    unsigned char *cb;    unsigned char *p_out;    int w, h;{  int x, y;  unsigned long *out = (unsigned long *)p_out;  unsigned long *out2 = out + w;  for (y=0; y<h; y++) {    for (x=0; x<w; x+=16) {      out[0] = out2[0]   = wpixel[lum[0]];      out[2] = out2[2]   = wpixel[lum[1]];      out[4] = out2[4]   = wpixel[lum[2]];      out[6] = out2[6]   = wpixel[lum[3]];      out[8] = out2[8]   = wpixel[lum[4]];      out[10] = out2[10] = wpixel[lum[5]];      out[12] = out2[12] = wpixel[lum[6]];      out[14] = out2[14] = wpixel[lum[7]];      out[16] = out2[16] = wpixel[lum[8]];      out[18] = out2[18] = wpixel[lum[9]];      out[20] = out2[20] = wpixel[lum[10]];      out[22] = out2[22] = wpixel[lum[11]];      out[24] = out2[24] = wpixel[lum[12]];      out[26] = out2[26] = wpixel[lum[13]];      out[28] = out2[28] = wpixel[lum[14]];      out[30] = out2[30] = wpixel[lum[15]];      out += 16;      out2 += 16;      lum += 16;    }  out += w;  out2 += w;  }}#endif /* def SIXTYFOUR_BIT */