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/* Copyright (c) 1995 Regents of the University of California */ |
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|
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#ifndef lint |
| 4 |
static char SCCSid[] = "$SunId$ LBL"; |
| 5 |
#endif |
| 6 |
|
| 7 |
/* |
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* Calibrate a scanned MacBeth Color Checker Chart |
| 9 |
* |
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* Produce a .cal file suitable for use with pcomb. |
| 11 |
*/ |
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|
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#include <stdio.h> |
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#ifdef MSDOS |
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#include <fcntl.h> |
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#endif |
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#include "color.h" |
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#include "resolu.h" |
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#include "pmap.h" |
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|
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/* MacBeth colors (CIE 1931, absolute white) */ |
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/* computed from spectral measurements */ |
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float mbxyY[24][3] = { |
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{0.462, 0.3769, 0.0932961}, /* DarkSkin */ |
| 25 |
{0.4108, 0.3542, 0.410348}, /* LightSkin */ |
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{0.2626, 0.267, 0.181554}, /* BlueSky */ |
| 27 |
{0.36, 0.4689, 0.108447}, /* Foliage */ |
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{0.2977, 0.2602, 0.248407}, /* BlueFlower */ |
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{0.2719, 0.3485, 0.401156}, /* BluishGreen */ |
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{0.52, 0.4197, 0.357899}, /* Orange */ |
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{0.229, 0.1866, 0.103911}, /* PurplishBlue */ |
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{0.4909, 0.3262, 0.242615}, /* ModerateRed */ |
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{0.3361, 0.2249, 0.0600102}, /* Purple */ |
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{0.3855, 0.4874, 0.42963}, /* YellowGreen */ |
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{0.4853, 0.4457, 0.476343}, /* OrangeYellow */ |
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{0.2026, 0.1369, 0.0529249}, /* Blue */ |
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{0.3007, 0.4822, 0.221226}, /* Green */ |
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{0.5805, 0.3238, 0.162167}, /* Red */ |
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{0.4617, 0.472, 0.64909}, /* Yellow */ |
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{0.4178, 0.2625, 0.233662}, /* Magenta */ |
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{0.2038, 0.2508, 0.167275}, /* Cyan */ |
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{0.3358, 0.337, 0.916877}, /* White */ |
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{0.3338, 0.3348, 0.604678}, /* Neutral.8 */ |
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{0.3333, 0.3349, 0.364566}, /* Neutral.65 */ |
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{0.3353, 0.3359, 0.200238}, /* Neutral.5 */ |
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{0.3363, 0.336, 0.0878721}, /* Neutral.35 */ |
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{0.3346, 0.3349, 0.0308383} /* Black */ |
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}; |
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|
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COLOR mbRGB[24]; /* MacBeth RGB values */ |
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|
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#define NMBNEU 6 /* Number of MacBeth neutral colors */ |
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short mbneu[NMBNEU] = {23,22,21,20,19,18}; |
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#define NMBMOD 3 /* Number of MacBeth moderate colors */ |
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short mbmod[NMBMOD] = {1,3,2}; |
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#define NMBSAT 6 /* Number of MacBeth saturated colors */ |
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short mbsat[NMBSAT] = {14,12,13,15,16,17}; |
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|
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int xmax, ymax; /* input image dimensions */ |
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int bounds[4][2]; /* image coordinates of chart corners */ |
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double imgxfm[3][3]; /* coordinate transformation matrix */ |
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|
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COLOR picRGB[24]; /* picture colors */ |
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|
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double bramp[NMBNEU][2]; /* brightness ramp */ |
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double solmat[3][3]; /* color mapping matrix */ |
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|
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FILE *debugfp = NULL; |
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char *progname; |
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|
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extern char *malloc(); |
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|
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|
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main(argc, argv) |
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int argc; |
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char **argv; |
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{ |
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int i; |
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|
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progname = argv[0]; |
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if (argc > 2 && !strcmp(argv[1], "-d")) { /* debug output */ |
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if ((debugfp = fopen(argv[2], "w")) == NULL) { |
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perror(argv[2]); |
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exit(1); |
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} |
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#ifdef MSDOS |
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setmode(fileno(debugfp), O_BINARY); |
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#endif |
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newheader("RADIANCE", debugfp); |
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printargs(argc, argv, debugfp); |
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argv += 2; |
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argc -= 2; |
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} |
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if (argc != 3 && argc != 11) |
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goto userr; |
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if (strcmp(argv[1], "-") && freopen(argv[1], "r", stdin) == NULL) { |
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perror(argv[1]); |
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exit(1); |
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} |
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if (strcmp(argv[2], "-") && freopen(argv[2], "w", stdout) == NULL) { |
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perror(argv[2]); |
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exit(1); |
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} |
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#ifdef MSDOS |
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setmode(fileno(stdin), O_BINARY); |
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#endif |
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if (checkheader(stdin, COLRFMT, NULL) < 0 || |
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fgetresolu(&xmax, &ymax, stdin) < 0) { |
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fprintf(stderr, "%s: bad input picture\n", progname); |
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exit(1); |
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} |
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/* get chart boundaries */ |
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if (argc == 11) { |
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for (i = 0; i < 4; i++) { |
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if (!isint(argv[2*i+3]) | !isint(argv[2*i+4])) |
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goto userr; |
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bounds[i][0] = atoi(argv[2*i+3]); |
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bounds[i][1] = atoi(argv[2*i+4]); |
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} |
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} else { |
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bounds[0][0] = bounds[2][0] = .029*xmax + .5; |
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bounds[0][1] = bounds[1][1] = .956*ymax + .5; |
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bounds[1][0] = bounds[3][0] = .971*xmax + .5; |
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bounds[2][1] = bounds[3][1] = .056*ymax + .5; |
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} |
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init(); /* initialize */ |
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getcolors(); /* get picture colors */ |
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putmapping(); /* put out color mapping */ |
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putdebug(); /* put out debug picture */ |
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exit(0); |
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userr: |
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fprintf(stderr, "Usage: %s [-d dbg.pic] input.pic output.cal [xul yul xur yur xll yll xlr ylr]\n", |
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progname); |
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exit(1); |
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} |
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|
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|
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init() /* initialize */ |
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{ |
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double quad[4][2]; |
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COLOR ctmp; |
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double d; |
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int i; |
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/* make coordinate transformation */ |
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quad[0][0] = bounds[0][0]; |
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quad[0][1] = bounds[0][1]; |
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quad[1][0] = bounds[1][0]; |
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quad[1][1] = bounds[1][1]; |
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quad[2][0] = bounds[3][0]; |
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quad[2][1] = bounds[3][1]; |
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quad[3][0] = bounds[2][0]; |
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quad[3][1] = bounds[2][1]; |
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|
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if (pmap_quad_rect(0., 0., 6., 4., quad, imgxfm) == PMAP_BAD) { |
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fprintf(stderr, "%s: bad chart boundaries\n", progname); |
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exit(1); |
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} |
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/* map MacBeth colors to RGB space */ |
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for (i = 0; i < 24; i++) { |
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d = mbxyY[i][2] / mbxyY[i][1]; |
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ctmp[0] = mbxyY[i][0] * d; |
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ctmp[1] = mbxyY[i][2]; |
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ctmp[2] = (1. - mbxyY[i][0] - mbxyY[i][1]) * d; |
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cie_rgb(mbRGB[i], ctmp); |
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} |
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} |
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|
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|
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int |
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chartndx(x, y) /* find color number for position */ |
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int x, y; |
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{ |
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double ipos[3], cpos[3]; |
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int ix, iy; |
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double fx, fy; |
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|
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ipos[0] = x; |
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ipos[1] = y; |
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ipos[2] = 1; |
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mx3d_transform(ipos, imgxfm, cpos); |
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cpos[0] /= cpos[2]; |
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cpos[1] /= cpos[2]; |
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if (cpos[0] < 0. || cpos[0] >= 6. || cpos[1] < 0. || cpos[1] >= 4.) |
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return(-1); |
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ix = cpos[0]; |
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iy = cpos[1]; |
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fx = cpos[0] - ix; |
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fy = cpos[1] - iy; |
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if (fx < .35 || fx >= .65 || fy < .35 || fy >= .65) |
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return(-1); |
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return(iy*6 + ix); |
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} |
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|
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|
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getcolors() /* load in picture colors */ |
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{ |
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COLR *scanln; |
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COLOR pval; |
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int ccount[24]; |
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double d; |
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int y; |
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register int x, i; |
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|
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scanln = (COLR *)malloc(xmax*sizeof(COLR)); |
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if (scanln == NULL) { |
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perror(progname); |
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exit(1); |
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} |
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for (i = 0; i < 24; i++) { |
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setcolor(picRGB[i], 0., 0., 0.); |
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ccount[i] = 0; |
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} |
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for (y = ymax-1; y >= 0; y--) { |
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if (freadcolrs(scanln, xmax, stdin) < 0) { |
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fprintf(stderr, "%s: error reading input picture\n", |
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progname); |
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exit(1); |
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} |
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for (x = 0; x < xmax; x++) { |
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i = chartndx(x, y); |
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if (i >= 0) { |
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colr_color(pval, scanln[x]); |
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addcolor(picRGB[i], pval); |
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ccount[i]++; |
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} |
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} |
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} |
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for (i = 0; i < 24; i++) { |
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if (ccount[i] == 0) { |
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fprintf(stderr, "%s: bad chart boundaries\n", |
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progname); |
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exit(1); |
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} |
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d = 1.0/ccount[i]; |
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scalecolor(picRGB[i], d); |
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} |
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free((char *)scanln); |
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} |
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|
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|
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double |
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bresp(x) /* piecewise linear interpolation of brightness */ |
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double x; |
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{ |
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register int n = NMBNEU; |
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|
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while (n > 0 && x < bramp[--n][0]) |
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; |
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return( ((bramp[n+1][0] - x)*bramp[n][1] + |
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(x - bramp[n][0])*bramp[n+1][1]) / |
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(bramp[n+1][0] - bramp[n][0]) ); |
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} |
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|
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|
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putmapping() /* compute and print mapping for pcomb -f */ |
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{ |
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float clrin[NMBMOD][3], clrout[NMBMOD][3]; |
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register int i, j; |
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/* compute piecewise luminance curve */ |
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for (i = 0; i < NMBNEU; i++) { |
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bramp[i][0] = bright(picRGB[mbneu[i]]); |
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bramp[i][1] = bright(mbRGB[mbneu[i]]); |
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} |
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/* compute color matrix */ |
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for (i = 0; i < NMBMOD; i++) |
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for (j = 0; j < 3; j++) { |
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clrin[i][j] = bresp(picRGB[mbmod[i]][j]); |
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clrout[i][j] = mbRGB[mbmod[i]][j]; |
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} |
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compsoln(clrin, clrout, NMBMOD); |
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/* print brightness mapping */ |
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printf("xval(i) : select(i, 0"); |
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for (i = 0; i < NMBNEU; i++) |
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printf(", %g", bramp[i][0]); |
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printf(");\n"); |
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printf("yval(i) : select(i, 0"); |
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for (i = 0; i < NMBNEU; i++) |
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printf(", %g", bramp[i][1]); |
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printf(");\n"); |
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printf("ifind(x,f,n) : if(1.5-n, 1, if(x-f(n), n, ifind(x,f,n-1)));\n"); |
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printf("binterp(i,x) : ((xval(i+1)-x)*yval(i) + (x-xval(i))*yval(i+1))/\n"); |
| 282 |
printf("\t\t(xval(i+1) - xval(i));\n"); |
| 283 |
printf("bresp(x) : binterp(ifind(x,xval,xval(0)-1), x);\n"); |
| 284 |
printf("nred = bresp(ri(1));\n"); |
| 285 |
printf("ngrn = bresp(gi(1));\n"); |
| 286 |
printf("nblu = bresp(bi(1));\n"); |
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/* print color mapping */ |
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printf("ro = %g*nred + %g*ngrn + %g*nblu\n", |
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solmat[0][0], solmat[1][0], solmat[2][0]); |
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printf("go = %g*nred + %g*ngrn + %g*nblu\n", |
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solmat[0][1], solmat[1][1], solmat[2][1]); |
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printf("bo = %g*nred + %g*ngrn + %g*nblu\n", |
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solmat[0][2], solmat[1][2], solmat[2][2]); |
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} |
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|
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|
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compsoln(cin, cout, n) /* solve 3x3 system */ |
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float cin[][3], cout[][3]; |
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int n; |
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{ |
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extern double mx3d_adjoint(), fabs(); |
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double mat[3][3], invmat[3][3]; |
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double det; |
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double colv[3], rowv[3]; |
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register int i, j; |
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|
| 307 |
if (n != 3) { |
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fprintf(stderr, "%s: inconsistent code!\n", progname); |
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exit(1); |
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} |
| 311 |
for (i = 0; i < 3; i++) |
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for (j = 0; j < 3; j++) |
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mat[i][j] = cin[j][i]; |
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det = mx3d_adjoint(mat, invmat); |
| 315 |
if (fabs(det) < 1e-4) { |
| 316 |
fprintf(stderr, "%s: cannot compute color mapping\n", |
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progname); |
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solmat[0][0] = solmat[1][1] = solmat[2][2] = 1.; |
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solmat[0][1] = solmat[0][2] = solmat[1][0] = |
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solmat[1][2] = solmat[2][0] = solmat[2][1] = 0.; |
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return; |
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} |
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for (i = 0; i < 3; i++) |
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for (j = 0; j < 3; j++) |
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invmat[i][j] /= det; |
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for (i = 0; i < 3; i++) { |
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for (j = 0; j < 3; j++) |
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rowv[j] = cout[j][i]; |
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mx3d_transform(rowv, invmat, colv); |
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for (j = 0; j < 3; j++) |
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solmat[j][i] = colv[j]; |
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} |
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} |
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|
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|
| 336 |
cvtcolor(cout, cin) /* convert color according to our mapping */ |
| 337 |
COLOR cout, cin; |
| 338 |
{ |
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double r, g, b; |
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double r1, g1, b1; |
| 341 |
|
| 342 |
r = bresp(colval(cin,RED)); |
| 343 |
g = bresp(colval(cin,GRN)); |
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b = bresp(colval(cin,BLU)); |
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r1 = r*solmat[0][0] + g*solmat[1][0] + b*solmat[2][0]; |
| 346 |
if (r1 < 0) r1 = 0; |
| 347 |
g1 = r*solmat[0][1] + g*solmat[1][1] + b*solmat[2][1]; |
| 348 |
if (g1 < 0) g1 = 0; |
| 349 |
b1 = r*solmat[0][2] + g*solmat[1][2] + b*solmat[2][2]; |
| 350 |
if (b1 < 0) b1 = 0; |
| 351 |
setcolor(cout, r1, g1, b1); |
| 352 |
} |
| 353 |
|
| 354 |
|
| 355 |
putdebug() /* put out debugging picture */ |
| 356 |
{ |
| 357 |
COLOR *scan; |
| 358 |
int y; |
| 359 |
register int x, i; |
| 360 |
|
| 361 |
if (debugfp == NULL) |
| 362 |
return; |
| 363 |
if (fseek(stdin, 0L, 0) == EOF) { |
| 364 |
fprintf(stderr, "%s: cannot seek on input picture\n", progname); |
| 365 |
exit(1); |
| 366 |
} |
| 367 |
getheader(stdin, NULL, NULL); /* skip input header */ |
| 368 |
fgetresolu(&xmax, &ymax, stdin); |
| 369 |
/* allocate scanline */ |
| 370 |
scan = (COLOR *)malloc(xmax*sizeof(COLOR)); |
| 371 |
if (scan == NULL) { |
| 372 |
perror(progname); |
| 373 |
exit(1); |
| 374 |
} |
| 375 |
/* finish debug header */ |
| 376 |
putc('\n', debugfp); |
| 377 |
fprtresolu(xmax, ymax, debugfp); |
| 378 |
for (y = ymax-1; y >= 0; y--) { |
| 379 |
if (freadscan(scan, xmax, stdin) < 0) { |
| 380 |
fprintf(stderr, "%s: error rereading input picture\n", |
| 381 |
progname); |
| 382 |
exit(1); |
| 383 |
} |
| 384 |
for (x = 0; x < xmax; x++) { |
| 385 |
i = chartndx(x, y); |
| 386 |
if (i < 0) |
| 387 |
cvtcolor(scan[x], scan[x]); |
| 388 |
else |
| 389 |
copycolor(scan[x], mbRGB[i]); |
| 390 |
} |
| 391 |
if (fwritescan(scan, xmax, debugfp) < 0) { |
| 392 |
fprintf(stderr, "%s: error writing debugging picture\n", |
| 393 |
progname); |
| 394 |
exit(1); |
| 395 |
} |
| 396 |
} |
| 397 |
free((char *)scan); |
| 398 |
} |
