| 1 |
/* Copyright (c) 1995 Regents of the University of California */ |
| 2 |
|
| 3 |
#ifndef lint |
| 4 |
static char SCCSid[] = "$SunId$ LBL"; |
| 5 |
#endif |
| 6 |
|
| 7 |
/* |
| 8 |
* Calibrate a scanned MacBeth Color Checker Chart |
| 9 |
* |
| 10 |
* Produce a .cal file suitable for use with pcomb. |
| 11 |
*/ |
| 12 |
|
| 13 |
#include <stdio.h> |
| 14 |
#ifdef MSDOS |
| 15 |
#include <fcntl.h> |
| 16 |
#endif |
| 17 |
#include "color.h" |
| 18 |
#include "resolu.h" |
| 19 |
#include "pmap.h" |
| 20 |
|
| 21 |
/* MacBeth colors */ |
| 22 |
#define DarkSkin 0 |
| 23 |
#define LightSkin 1 |
| 24 |
#define BlueSky 2 |
| 25 |
#define Foliage 3 |
| 26 |
#define BlueFlower 4 |
| 27 |
#define BluishGreen 5 |
| 28 |
#define Orange 6 |
| 29 |
#define PurplishBlue 7 |
| 30 |
#define ModerateRed 8 |
| 31 |
#define Purple 9 |
| 32 |
#define YellowGreen 10 |
| 33 |
#define OrangeYellow 11 |
| 34 |
#define Blue 12 |
| 35 |
#define Green 13 |
| 36 |
#define Red 14 |
| 37 |
#define Yellow 15 |
| 38 |
#define Magenta 16 |
| 39 |
#define Cyan 17 |
| 40 |
#define White 18 |
| 41 |
#define Neutral8 19 |
| 42 |
#define Neutral65 20 |
| 43 |
#define Neutral5 21 |
| 44 |
#define Neutral35 22 |
| 45 |
#define Black 23 |
| 46 |
/* computed from 5nm spectral measurements */ |
| 47 |
/* CIE 1931 2 degree obs, equal-energy white */ |
| 48 |
float mbxyY[24][3] = { |
| 49 |
{0.462, 0.3769, 0.0932961}, /* DarkSkin */ |
| 50 |
{0.4108, 0.3542, 0.410348}, /* LightSkin */ |
| 51 |
{0.2626, 0.267, 0.181554}, /* BlueSky */ |
| 52 |
{0.36, 0.4689, 0.108447}, /* Foliage */ |
| 53 |
{0.2977, 0.2602, 0.248407}, /* BlueFlower */ |
| 54 |
{0.2719, 0.3485, 0.401156}, /* BluishGreen */ |
| 55 |
{0.52, 0.4197, 0.357899}, /* Orange */ |
| 56 |
{0.229, 0.1866, 0.103911}, /* PurplishBlue */ |
| 57 |
{0.4909, 0.3262, 0.242615}, /* ModerateRed */ |
| 58 |
{0.3361, 0.2249, 0.0600102}, /* Purple */ |
| 59 |
{0.3855, 0.4874, 0.42963}, /* YellowGreen */ |
| 60 |
{0.4853, 0.4457, 0.476343}, /* OrangeYellow */ |
| 61 |
{0.2026, 0.1369, 0.0529249}, /* Blue */ |
| 62 |
{0.3007, 0.4822, 0.221226}, /* Green */ |
| 63 |
{0.5805, 0.3238, 0.162167}, /* Red */ |
| 64 |
{0.4617, 0.472, 0.64909}, /* Yellow */ |
| 65 |
{0.4178, 0.2625, 0.233662}, /* Magenta */ |
| 66 |
{0.2038, 0.2508, 0.167275}, /* Cyan */ |
| 67 |
{0.3358, 0.337, 0.916877}, /* White */ |
| 68 |
{0.3338, 0.3348, 0.604678}, /* Neutral.8 */ |
| 69 |
{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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}; |
| 74 |
|
| 75 |
COLOR mbRGB[24]; /* MacBeth RGB values */ |
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|
| 77 |
#define NMBNEU 6 /* Number of MacBeth neutral colors */ |
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short mbneu[NMBNEU] = {Black,Neutral35,Neutral5,Neutral65,Neutral8,White}; |
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|
| 80 |
#define NMBMOD 17 /* Number of MacBeth unsaturated colors */ |
| 81 |
short mbmod[NMBMOD] = { |
| 82 |
DarkSkin,LightSkin,BlueSky,Foliage,BlueFlower,BluishGreen, |
| 83 |
Orange,PurplishBlue,ModerateRed,Purple,YellowGreen, |
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Black,Neutral35,Neutral5,Neutral65,Neutral8,White |
| 85 |
}; |
| 86 |
|
| 87 |
#define NMBSAT 8 /* Number of MacBeth saturated colors */ |
| 88 |
short mbsat[NMBSAT] = { |
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Red,Green,Blue,Magenta,Yellow,Cyan, |
| 90 |
Orange,OrangeYellow |
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}; |
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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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COLOR bramp[NMBNEU][2]; /* brightness ramp (per primary) */ |
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double solmat[3][3]; /* color mapping matrix */ |
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|
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FILE *debugfp = NULL; /* debug output picture */ |
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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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compute(); /* compute color mapping */ |
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/* print comment */ |
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printf("{ Color correction file computed by %s }\n", progname); |
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printf("{ from scanned MacBetch color chart %s }\n", argv[1]); |
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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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/* 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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} |
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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++) { |
| 256 |
if (ccount[i] == 0) { |
| 257 |
fprintf(stderr, "%s: bad chart boundaries\n", |
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progname); |
| 259 |
exit(1); |
| 260 |
} |
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d = 1.0/ccount[i]; |
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scalecolor(picRGB[i], d); |
| 263 |
} |
| 264 |
free((char *)scanln); |
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} |
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|
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|
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bresp(y, x) /* piecewise linear interpolation of primaries */ |
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COLOR y, x; |
| 270 |
{ |
| 271 |
double cv[3]; |
| 272 |
register int i, n; |
| 273 |
|
| 274 |
for (i = 0; i < 3; i++) { |
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n = NMBNEU; |
| 276 |
while (n > 0 && colval(x,i) < colval(bramp[--n][0],i)) |
| 277 |
; |
| 278 |
cv[i] = ((colval(bramp[n+1][0],i) - colval(x,i)) * |
| 279 |
colval(bramp[n][1],i) + |
| 280 |
(colval(x,i) - colval(bramp[n][0],i)) * |
| 281 |
colval(bramp[n+1][1],i)) / |
| 282 |
(colval(bramp[n+1][0],i) - colval(bramp[n][0],i)); |
| 283 |
if (cv[i] < 0.) cv[i] = 0.; |
| 284 |
} |
| 285 |
setcolor(y, cv[0], cv[1], cv[2]); |
| 286 |
} |
| 287 |
|
| 288 |
|
| 289 |
compute() /* compute color mapping */ |
| 290 |
{ |
| 291 |
COLOR clrin[NMBMOD], clrout[NMBMOD]; |
| 292 |
COLOR ctmp; |
| 293 |
double d; |
| 294 |
register int i; |
| 295 |
/* map MacBeth colors to RGB space */ |
| 296 |
for (i = 0; i < 24; i++) { |
| 297 |
d = mbxyY[i][2] / mbxyY[i][1]; |
| 298 |
ctmp[0] = mbxyY[i][0] * d; |
| 299 |
ctmp[1] = mbxyY[i][2]; |
| 300 |
ctmp[2] = (1. - mbxyY[i][0] - mbxyY[i][1]) * d; |
| 301 |
cie_rgb(mbRGB[i], ctmp); |
| 302 |
} |
| 303 |
/* compute piecewise luminance curve */ |
| 304 |
for (i = 0; i < NMBNEU; i++) { |
| 305 |
copycolor(bramp[i][0], picRGB[mbneu[i]]); |
| 306 |
copycolor(bramp[i][1], mbRGB[mbneu[i]]); |
| 307 |
} |
| 308 |
/* compute color matrix */ |
| 309 |
for (i = 0; i < NMBMOD; i++) { |
| 310 |
bresp(clrin[i], picRGB[mbmod[i]]); |
| 311 |
copycolor(clrout[i], mbRGB[mbmod[i]]); |
| 312 |
} |
| 313 |
compsoln(clrin, clrout, NMBMOD); |
| 314 |
} |
| 315 |
|
| 316 |
|
| 317 |
putmapping() /* put out color mapping for pcomb -f */ |
| 318 |
{ |
| 319 |
static char cchar[3] = {'r', 'g', 'b'}; |
| 320 |
register int i, j; |
| 321 |
/* print brightness mapping */ |
| 322 |
for (j = 0; j < 3; j++) { |
| 323 |
printf("%cxa(i) : select(i", cchar[j]); |
| 324 |
for (i = 0; i < NMBNEU; i++) |
| 325 |
printf(",%g", colval(bramp[i][0],j)); |
| 326 |
printf(");\n"); |
| 327 |
printf("%cya(i) : select(i", cchar[j]); |
| 328 |
for (i = 0; i < NMBNEU; i++) |
| 329 |
printf(",%g", colval(bramp[i][1],j)); |
| 330 |
printf(");\n"); |
| 331 |
printf("%c = %ci(1);\n", cchar[j], cchar[j]); |
| 332 |
printf("%cfi(n) = if(n-%g, %d, if(%cxa(n+1)-%c, n, %cfi(n+1)));\n", |
| 333 |
cchar[j], NMBNEU-1.5, NMBNEU-1, cchar[j], |
| 334 |
cchar[j], cchar[j]); |
| 335 |
printf("%cndx = %cfi(1);\n", cchar[j], cchar[j]); |
| 336 |
printf("%cn = ((%cxa(%cndx+1)-%c)*%cya(%cndx) + ", |
| 337 |
cchar[j], cchar[j], cchar[j], |
| 338 |
cchar[j], cchar[j], cchar[j]); |
| 339 |
printf("(%c-%cxa(%cndx))*%cya(%cndx+1)) /\n", |
| 340 |
cchar[j], cchar[j], cchar[j], |
| 341 |
cchar[j], cchar[j]); |
| 342 |
printf("\t\t(%cxa(%cndx+1) - %cxa(%cndx)) ;\n", |
| 343 |
cchar[j], cchar[j], cchar[j], cchar[j]); |
| 344 |
} |
| 345 |
/* print color mapping */ |
| 346 |
printf("ro = %g*rn + %g*gn + %g*bn ;\n", |
| 347 |
solmat[0][0], solmat[0][1], solmat[0][2]); |
| 348 |
printf("go = %g*rn + %g*gn + %g*bn ;\n", |
| 349 |
solmat[1][0], solmat[1][1], solmat[1][2]); |
| 350 |
printf("bo = %g*rn + %g*gn + %g*bn ;\n", |
| 351 |
solmat[2][0], solmat[2][1], solmat[2][2]); |
| 352 |
} |
| 353 |
|
| 354 |
|
| 355 |
compsoln(cin, cout, n) /* solve 3xN system using least-squares */ |
| 356 |
COLOR cin[], cout[]; |
| 357 |
int n; |
| 358 |
{ |
| 359 |
extern double mx3d_adjoint(), fabs(); |
| 360 |
double mat[3][3], invmat[3][3]; |
| 361 |
double det; |
| 362 |
double colv[3], rowv[3]; |
| 363 |
register int i, j, k; |
| 364 |
|
| 365 |
if (n < 3 | n > NMBMOD) { |
| 366 |
fprintf(stderr, "%s: inconsistent code!\n", progname); |
| 367 |
exit(1); |
| 368 |
} |
| 369 |
if (n == 3) |
| 370 |
for (i = 0; i < 3; i++) |
| 371 |
for (j = 0; j < 3; j++) |
| 372 |
mat[i][j] = colval(cin[j],i); |
| 373 |
else { /* compute A^t A */ |
| 374 |
for (i = 0; i < 3; i++) |
| 375 |
for (j = i; j < 3; j++) { |
| 376 |
mat[i][j] = 0.; |
| 377 |
for (k = 0; k < n; k++) |
| 378 |
mat[i][j] += colval(cin[k],i) * |
| 379 |
colval(cin[k],j); |
| 380 |
} |
| 381 |
for (i = 1; i < 3; i++) /* using symmetry */ |
| 382 |
for (j = 0; j < i; j++) |
| 383 |
mat[i][j] = mat[j][i]; |
| 384 |
} |
| 385 |
det = mx3d_adjoint(mat, invmat); |
| 386 |
if (fabs(det) < 1e-4) { |
| 387 |
fprintf(stderr, "%s: cannot compute color mapping\n", |
| 388 |
progname); |
| 389 |
solmat[0][0] = solmat[1][1] = solmat[2][2] = 1.; |
| 390 |
solmat[0][1] = solmat[0][2] = solmat[1][0] = |
| 391 |
solmat[1][2] = solmat[2][0] = solmat[2][1] = 0.; |
| 392 |
return; |
| 393 |
} |
| 394 |
for (i = 0; i < 3; i++) |
| 395 |
for (j = 0; j < 3; j++) |
| 396 |
invmat[i][j] /= det; |
| 397 |
for (i = 0; i < 3; i++) { |
| 398 |
if (n == 3) |
| 399 |
for (j = 0; j < 3; j++) |
| 400 |
colv[j] = colval(cout[j],i); |
| 401 |
else |
| 402 |
for (j = 0; j < 3; j++) { |
| 403 |
colv[j] = 0.; |
| 404 |
for (k = 0; k < n; k++) |
| 405 |
colv[j] += colval(cout[k],i) * |
| 406 |
colval(cin[k],j); |
| 407 |
} |
| 408 |
mx3d_transform(colv, invmat, rowv); |
| 409 |
for (j = 0; j < 3; j++) |
| 410 |
solmat[i][j] = rowv[j]; |
| 411 |
} |
| 412 |
} |
| 413 |
|
| 414 |
|
| 415 |
cvtcolor(cout, cin) /* convert color according to our mapping */ |
| 416 |
COLOR cout, cin; |
| 417 |
{ |
| 418 |
double r, g, b; |
| 419 |
|
| 420 |
bresp(cout, cin); |
| 421 |
r = colval(cout,0)*solmat[0][0] + colval(cout,1)*solmat[0][1] |
| 422 |
+ colval(cout,2)*solmat[0][2]; |
| 423 |
if (r < 0) r = 0; |
| 424 |
g = colval(cout,0)*solmat[1][0] + colval(cout,1)*solmat[1][1] |
| 425 |
+ colval(cout,2)*solmat[1][2]; |
| 426 |
if (g < 0) g = 0; |
| 427 |
b = colval(cout,0)*solmat[2][0] + colval(cout,1)*solmat[2][1] |
| 428 |
+ colval(cout,2)*solmat[2][2]; |
| 429 |
if (b < 0) b = 0; |
| 430 |
setcolor(cout, r, g, b); |
| 431 |
} |
| 432 |
|
| 433 |
|
| 434 |
putdebug() /* put out debugging picture */ |
| 435 |
{ |
| 436 |
COLOR *scan; |
| 437 |
int y; |
| 438 |
register int x, i; |
| 439 |
|
| 440 |
if (debugfp == NULL) |
| 441 |
return; |
| 442 |
if (fseek(stdin, 0L, 0) == EOF) { |
| 443 |
fprintf(stderr, "%s: cannot seek on input picture\n", progname); |
| 444 |
exit(1); |
| 445 |
} |
| 446 |
getheader(stdin, NULL, NULL); /* skip input header */ |
| 447 |
fgetresolu(&xmax, &ymax, stdin); |
| 448 |
/* allocate scanline */ |
| 449 |
scan = (COLOR *)malloc(xmax*sizeof(COLOR)); |
| 450 |
if (scan == NULL) { |
| 451 |
perror(progname); |
| 452 |
exit(1); |
| 453 |
} |
| 454 |
/* finish debug header */ |
| 455 |
putc('\n', debugfp); |
| 456 |
fprtresolu(xmax, ymax, debugfp); |
| 457 |
for (y = ymax-1; y >= 0; y--) { |
| 458 |
if (freadscan(scan, xmax, stdin) < 0) { |
| 459 |
fprintf(stderr, "%s: error rereading input picture\n", |
| 460 |
progname); |
| 461 |
exit(1); |
| 462 |
} |
| 463 |
for (x = 0; x < xmax; x++) { |
| 464 |
i = chartndx(x, y); |
| 465 |
if (i < 0) |
| 466 |
cvtcolor(scan[x], scan[x]); |
| 467 |
else |
| 468 |
copycolor(scan[x], mbRGB[i]); |
| 469 |
} |
| 470 |
if (fwritescan(scan, xmax, debugfp) < 0) { |
| 471 |
fprintf(stderr, "%s: error writing debugging picture\n", |
| 472 |
progname); |
| 473 |
exit(1); |
| 474 |
} |
| 475 |
} |
| 476 |
free((char *)scan); |
| 477 |
} |
