1 |
greg |
1.1 |
#ifndef lint |
2 |
greg |
2.15 |
static const char RCSid[] = "$Id: spec_rgb.c,v 2.14 2006/03/23 22:01:43 greg Exp $"; |
3 |
greg |
1.1 |
#endif |
4 |
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/* |
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* Convert colors and spectral ranges. |
6 |
greg |
2.11 |
* Added von Kries white-balance calculations 10/01 (GW). |
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* |
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* Externals declared in color.h |
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*/ |
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greg |
2.12 |
#include "copyright.h" |
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greg |
1.1 |
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greg |
2.13 |
#include <stdio.h> |
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#include <string.h> |
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greg |
1.1 |
#include "color.h" |
16 |
greg |
2.11 |
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#define CEPS 1e-4 /* color epsilon */ |
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#define CEQ(v1,v2) ((v1) <= (v2)+CEPS && (v2) <= (v1)+CEPS) |
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greg |
1.1 |
|
21 |
greg |
2.11 |
#define XYEQ(c1,c2) (CEQ((c1)[CIEX],(c2)[CIEX]) && CEQ((c1)[CIEY],(c2)[CIEY])) |
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greg |
2.5 |
|
23 |
gwlarson |
2.10 |
|
24 |
greg |
2.11 |
RGBPRIMS stdprims = STDPRIMS; /* standard primary chromaticities */ |
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greg |
2.5 |
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26 |
greg |
2.8 |
COLOR cblack = BLKCOLOR; /* global black color */ |
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COLOR cwhite = WHTCOLOR; /* global white color */ |
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greg |
2.11 |
float xyneu[2] = {1./3., 1./3.}; /* neutral xy chromaticities */ |
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greg |
1.1 |
/* |
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* The following table contains the CIE tristimulus integrals |
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* for X, Y, and Z. The table is cumulative, so that |
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* each color coordinate integrates to 1. |
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*/ |
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#define STARTWL 380 /* starting wavelength (nanometers) */ |
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#define INCWL 10 /* wavelength increment */ |
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#define NINC 40 /* # of values */ |
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static BYTE chroma[3][NINC] = { |
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{ /* X */ |
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0, 0, 0, 2, 6, 13, 22, 30, 36, 41, |
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42, 43, 43, 44, 46, 52, 60, 71, 87, 106, |
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128, 153, 178, 200, 219, 233, 243, 249, 252, 254, |
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255, 255, 255, 255, 255, 255, 255, 255, 255, 255 |
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}, { /* Y */ |
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0, 0, 0, 0, 0, 1, 2, 4, 7, 11, |
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17, 24, 34, 48, 64, 84, 105, 127, 148, 169, |
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188, 205, 220, 232, 240, 246, 250, 253, 254, 255, |
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255, 255, 255, 255, 255, 255, 255, 255, 255, 255 |
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}, { /* Z */ |
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0, 0, 2, 10, 32, 66, 118, 153, 191, 220, |
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237, 246, 251, 253, 254, 255, 255, 255, 255, 255, |
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255, 255, 255, 255, 255, 255, 255, 255, 255, 255, |
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255, 255, 255, 255, 255, 255, 255, 255, 255, 255 |
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} |
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}; |
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greg |
2.11 |
COLORMAT xyz2rgbmat = { /* XYZ to RGB (no white balance) */ |
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greg |
2.3 |
{(CIE_y_g - CIE_y_b - CIE_x_b*CIE_y_g + CIE_y_b*CIE_x_g)/CIE_C_rD, |
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(CIE_x_b - CIE_x_g - CIE_x_b*CIE_y_g + CIE_x_g*CIE_y_b)/CIE_C_rD, |
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(CIE_x_g*CIE_y_b - CIE_x_b*CIE_y_g)/CIE_C_rD}, |
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{(CIE_y_b - CIE_y_r - CIE_y_b*CIE_x_r + CIE_y_r*CIE_x_b)/CIE_C_gD, |
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(CIE_x_r - CIE_x_b - CIE_x_r*CIE_y_b + CIE_x_b*CIE_y_r)/CIE_C_gD, |
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(CIE_x_b*CIE_y_r - CIE_x_r*CIE_y_b)/CIE_C_gD}, |
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{(CIE_y_r - CIE_y_g - CIE_y_r*CIE_x_g + CIE_y_g*CIE_x_r)/CIE_C_bD, |
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(CIE_x_g - CIE_x_r - CIE_x_g*CIE_y_r + CIE_x_r*CIE_y_g)/CIE_C_bD, |
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(CIE_x_r*CIE_y_g - CIE_x_g*CIE_y_r)/CIE_C_bD} |
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greg |
1.2 |
}; |
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greg |
1.1 |
|
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greg |
2.11 |
COLORMAT rgb2xyzmat = { /* RGB to XYZ (no white balance) */ |
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greg |
2.4 |
{CIE_x_r*CIE_C_rD/CIE_D,CIE_x_g*CIE_C_gD/CIE_D,CIE_x_b*CIE_C_bD/CIE_D}, |
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{CIE_y_r*CIE_C_rD/CIE_D,CIE_y_g*CIE_C_gD/CIE_D,CIE_y_b*CIE_C_bD/CIE_D}, |
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{(1.-CIE_x_r-CIE_y_r)*CIE_C_rD/CIE_D, |
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(1.-CIE_x_g-CIE_y_g)*CIE_C_gD/CIE_D, |
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(1.-CIE_x_b-CIE_y_b)*CIE_C_bD/CIE_D} |
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}; |
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greg |
1.2 |
|
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greg |
2.11 |
COLORMAT vkmat = { /* Sharp primary matrix */ |
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{ 1.2694, -0.0988, -0.1706}, |
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{-0.8364, 1.8006, 0.0357}, |
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{ 0.0297, -0.0315, 1.0018} |
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}; |
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COLORMAT ivkmat = { /* inverse Sharp primary matrix */ |
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{ 0.8156, 0.0472, 0.1372}, |
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{ 0.3791, 0.5769, 0.0440}, |
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{-0.0123, 0.0167, 0.9955} |
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}; |
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greg |
1.2 |
|
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greg |
2.4 |
|
93 |
greg |
2.11 |
void |
94 |
greg |
2.15 |
spec_rgb( /* compute RGB color from spectral range */ |
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COLOR col, |
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int s, |
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int e |
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) |
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greg |
1.1 |
{ |
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COLOR ciecolor; |
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spec_cie(ciecolor, s, e); |
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cie_rgb(col, ciecolor); |
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} |
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106 |
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greg |
2.11 |
void |
108 |
greg |
2.15 |
spec_cie( /* compute a color from a spectral range */ |
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COLOR col, /* returned color */ |
110 |
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int s, /* starting and ending wavelengths */ |
111 |
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int e |
112 |
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) |
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greg |
1.1 |
{ |
114 |
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register int i, d, r; |
115 |
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116 |
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s -= STARTWL; |
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if (s < 0) |
118 |
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s = 0; |
119 |
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120 |
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e -= STARTWL; |
121 |
greg |
1.2 |
if (e <= s) { |
122 |
greg |
2.5 |
col[CIEX] = col[CIEY] = col[CIEZ] = 0.0; |
123 |
greg |
1.2 |
return; |
124 |
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} |
125 |
greg |
1.1 |
if (e >= INCWL*(NINC - 1)) |
126 |
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e = INCWL*(NINC - 1) - 1; |
127 |
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128 |
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d = e / INCWL; /* interpolate values */ |
129 |
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r = e % INCWL; |
130 |
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for (i = 0; i < 3; i++) |
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col[i] = chroma[i][d]*(INCWL - r) + chroma[i][d + 1]*r; |
132 |
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133 |
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d = s / INCWL; |
134 |
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r = s % INCWL; |
135 |
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for (i = 0; i < 3; i++) |
136 |
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col[i] -= chroma[i][d]*(INCWL - r) - chroma[i][d + 1]*r; |
137 |
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138 |
greg |
2.5 |
col[CIEX] = (col[CIEX] + 0.5) * (1./(256*INCWL)); |
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col[CIEY] = (col[CIEY] + 0.5) * (1./(256*INCWL)); |
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col[CIEZ] = (col[CIEZ] + 0.5) * (1./(256*INCWL)); |
141 |
greg |
1.1 |
} |
142 |
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143 |
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144 |
greg |
2.11 |
void |
145 |
greg |
2.15 |
cie_rgb( /* convert CIE color to standard RGB */ |
146 |
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COLOR rgb, |
147 |
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COLOR xyz |
148 |
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) |
149 |
greg |
2.8 |
{ |
150 |
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colortrans(rgb, xyz2rgbmat, xyz); |
151 |
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clipgamut(rgb, xyz[CIEY], CGAMUT_LOWER, cblack, cwhite); |
152 |
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} |
153 |
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154 |
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155 |
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int |
156 |
greg |
2.15 |
clipgamut( /* clip to gamut cube */ |
157 |
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COLOR col, |
158 |
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double brt, |
159 |
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int gamut, |
160 |
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COLOR lower, |
161 |
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COLOR upper |
162 |
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) |
163 |
greg |
2.8 |
{ |
164 |
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int rflags = 0; |
165 |
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double brtmin, brtmax, v, vv; |
166 |
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COLOR cgry; |
167 |
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register int i; |
168 |
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/* check for no check */ |
169 |
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if (gamut == 0) return(0); |
170 |
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/* check brightness limits */ |
171 |
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brtmin = 1./3.*(lower[0]+lower[1]+lower[2]); |
172 |
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if (gamut & CGAMUT_LOWER && brt < brtmin) { |
173 |
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copycolor(col, lower); |
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return(CGAMUT_LOWER); |
175 |
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} |
176 |
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brtmax = 1./3.*(upper[0]+upper[1]+upper[2]); |
177 |
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if (gamut & CGAMUT_UPPER && brt > brtmax) { |
178 |
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copycolor(col, upper); |
179 |
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return(CGAMUT_UPPER); |
180 |
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} |
181 |
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/* compute equivalent grey */ |
182 |
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v = (brt - brtmin)/(brtmax - brtmin); |
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for (i = 0; i < 3; i++) |
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cgry[i] = v*upper[i] + (1.-v)*lower[i]; |
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vv = 1.; /* check each limit */ |
186 |
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for (i = 0; i < 3; i++) |
187 |
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if (gamut & CGAMUT_LOWER && col[i] < lower[i]) { |
188 |
greg |
2.14 |
v = (lower[i] - cgry[i])/(col[i] - cgry[i]); |
189 |
greg |
2.8 |
if (v < vv) vv = v; |
190 |
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rflags |= CGAMUT_LOWER; |
191 |
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} else if (gamut & CGAMUT_UPPER && col[i] > upper[i]) { |
192 |
greg |
2.14 |
v = (upper[i] - cgry[i])/(col[i] - cgry[i]); |
193 |
greg |
2.8 |
if (v < vv) vv = v; |
194 |
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rflags |= CGAMUT_UPPER; |
195 |
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} |
196 |
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if (rflags) /* desaturate to cube face */ |
197 |
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for (i = 0; i < 3; i++) |
198 |
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col[i] = vv*col[i] + (1.-vv)*cgry[i]; |
199 |
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return(rflags); |
200 |
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} |
201 |
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202 |
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203 |
greg |
2.11 |
void |
204 |
greg |
2.15 |
colortrans( /* convert c1 by mat and put into c2 */ |
205 |
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register COLOR c2, |
206 |
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register COLORMAT mat, |
207 |
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register COLOR c1 |
208 |
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) |
209 |
greg |
1.1 |
{ |
210 |
greg |
2.9 |
COLOR cout; |
211 |
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212 |
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cout[0] = mat[0][0]*c1[0] + mat[0][1]*c1[1] + mat[0][2]*c1[2]; |
213 |
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cout[1] = mat[1][0]*c1[0] + mat[1][1]*c1[1] + mat[1][2]*c1[2]; |
214 |
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cout[2] = mat[2][0]*c1[0] + mat[2][1]*c1[1] + mat[2][2]*c1[2]; |
215 |
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216 |
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copycolor(c2, cout); |
217 |
greg |
2.4 |
} |
218 |
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219 |
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220 |
greg |
2.11 |
void |
221 |
greg |
2.15 |
multcolormat( /* multiply m1 by m2 and put into m3 */ |
222 |
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COLORMAT m3, /* m3 can be either m1 or m2 w/o harm */ |
223 |
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COLORMAT m2, |
224 |
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COLORMAT m1 |
225 |
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) |
226 |
greg |
2.4 |
{ |
227 |
greg |
2.5 |
COLORMAT mt; |
228 |
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register int i, j; |
229 |
greg |
2.4 |
|
230 |
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for (i = 0; i < 3; i++) |
231 |
greg |
2.5 |
for (j = 0; j < 3; j++) |
232 |
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mt[i][j] = m1[i][0]*m2[0][j] + |
233 |
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m1[i][1]*m2[1][j] + |
234 |
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m1[i][2]*m2[2][j] ; |
235 |
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cpcolormat(m3, mt); |
236 |
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} |
237 |
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238 |
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239 |
greg |
2.15 |
int |
240 |
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colorprimsOK( /* are color primaries reasonable? */ |
241 |
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RGBPRIMS pr |
242 |
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) |
243 |
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{ |
244 |
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int i; |
245 |
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246 |
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for (i = 0; i < 4; i++) { |
247 |
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if ((pr[i][CIEX] <= CEPS) | (pr[i][CIEY] <= CEPS)) |
248 |
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return(0); |
249 |
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if ((pr[i][CIEX] >= 1.-CEPS) | (pr[i][CIEY] >= 1.-CEPS)) |
250 |
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return(0); |
251 |
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} |
252 |
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return(1); |
253 |
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} |
254 |
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255 |
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256 |
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257 |
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int |
258 |
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compxyz2rgbmat( /* compute conversion from CIE to RGB space */ |
259 |
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COLORMAT mat, |
260 |
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register RGBPRIMS pr |
261 |
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) |
262 |
greg |
2.5 |
{ |
263 |
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double C_rD, C_gD, C_bD; |
264 |
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265 |
greg |
2.6 |
if (pr == stdprims) { /* can use xyz2rgbmat */ |
266 |
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cpcolormat(mat, xyz2rgbmat); |
267 |
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return; |
268 |
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} |
269 |
greg |
2.15 |
if (CEQ(pr[WHT][CIEX],0.) | CEQ(pr[WHT][CIEY],0.)) |
270 |
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return(0); |
271 |
greg |
2.5 |
C_rD = (1./pr[WHT][CIEY]) * |
272 |
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( pr[WHT][CIEX]*(pr[GRN][CIEY] - pr[BLU][CIEY]) - |
273 |
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pr[WHT][CIEY]*(pr[GRN][CIEX] - pr[BLU][CIEX]) + |
274 |
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pr[GRN][CIEX]*pr[BLU][CIEY] - pr[BLU][CIEX]*pr[GRN][CIEY] ) ; |
275 |
greg |
2.15 |
if (CEQ(C_rD,0.)) |
276 |
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return(0); |
277 |
greg |
2.5 |
C_gD = (1./pr[WHT][CIEY]) * |
278 |
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( pr[WHT][CIEX]*(pr[BLU][CIEY] - pr[RED][CIEY]) - |
279 |
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pr[WHT][CIEY]*(pr[BLU][CIEX] - pr[RED][CIEX]) - |
280 |
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pr[RED][CIEX]*pr[BLU][CIEY] + pr[BLU][CIEX]*pr[RED][CIEY] ) ; |
281 |
greg |
2.15 |
if (CEQ(C_gD,0.)) |
282 |
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return(0); |
283 |
greg |
2.5 |
C_bD = (1./pr[WHT][CIEY]) * |
284 |
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( pr[WHT][CIEX]*(pr[RED][CIEY] - pr[GRN][CIEY]) - |
285 |
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pr[WHT][CIEY]*(pr[RED][CIEX] - pr[GRN][CIEX]) + |
286 |
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pr[RED][CIEX]*pr[GRN][CIEY] - pr[GRN][CIEX]*pr[RED][CIEY] ) ; |
287 |
greg |
2.15 |
if (CEQ(C_bD,0.)) |
288 |
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return(0); |
289 |
greg |
2.5 |
mat[0][0] = (pr[GRN][CIEY] - pr[BLU][CIEY] - |
290 |
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pr[BLU][CIEX]*pr[GRN][CIEY] + |
291 |
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pr[BLU][CIEY]*pr[GRN][CIEX])/C_rD ; |
292 |
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mat[0][1] = (pr[BLU][CIEX] - pr[GRN][CIEX] - |
293 |
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pr[BLU][CIEX]*pr[GRN][CIEY] + |
294 |
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pr[GRN][CIEX]*pr[BLU][CIEY])/C_rD ; |
295 |
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mat[0][2] = (pr[GRN][CIEX]*pr[BLU][CIEY] - |
296 |
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pr[BLU][CIEX]*pr[GRN][CIEY])/C_rD ; |
297 |
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mat[1][0] = (pr[BLU][CIEY] - pr[RED][CIEY] - |
298 |
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pr[BLU][CIEY]*pr[RED][CIEX] + |
299 |
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pr[RED][CIEY]*pr[BLU][CIEX])/C_gD ; |
300 |
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mat[1][1] = (pr[RED][CIEX] - pr[BLU][CIEX] - |
301 |
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pr[RED][CIEX]*pr[BLU][CIEY] + |
302 |
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pr[BLU][CIEX]*pr[RED][CIEY])/C_gD ; |
303 |
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mat[1][2] = (pr[BLU][CIEX]*pr[RED][CIEY] - |
304 |
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pr[RED][CIEX]*pr[BLU][CIEY])/C_gD ; |
305 |
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mat[2][0] = (pr[RED][CIEY] - pr[GRN][CIEY] - |
306 |
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pr[RED][CIEY]*pr[GRN][CIEX] + |
307 |
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pr[GRN][CIEY]*pr[RED][CIEX])/C_bD ; |
308 |
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mat[2][1] = (pr[GRN][CIEX] - pr[RED][CIEX] - |
309 |
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pr[GRN][CIEX]*pr[RED][CIEY] + |
310 |
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pr[RED][CIEX]*pr[GRN][CIEY])/C_bD ; |
311 |
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mat[2][2] = (pr[RED][CIEX]*pr[GRN][CIEY] - |
312 |
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pr[GRN][CIEX]*pr[RED][CIEY])/C_bD ; |
313 |
greg |
2.15 |
return(1); |
314 |
greg |
2.5 |
} |
315 |
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316 |
|
|
|
317 |
greg |
2.15 |
int |
318 |
|
|
comprgb2xyzmat( /* compute conversion from RGB to CIE space */ |
319 |
|
|
COLORMAT mat, |
320 |
|
|
register RGBPRIMS pr |
321 |
|
|
) |
322 |
greg |
2.5 |
{ |
323 |
|
|
double C_rD, C_gD, C_bD, D; |
324 |
|
|
|
325 |
greg |
2.6 |
if (pr == stdprims) { /* can use rgb2xyzmat */ |
326 |
|
|
cpcolormat(mat, rgb2xyzmat); |
327 |
|
|
return; |
328 |
|
|
} |
329 |
greg |
2.15 |
if (CEQ(pr[WHT][CIEX],0.) | CEQ(pr[WHT][CIEY],0.)) |
330 |
|
|
return(0); |
331 |
greg |
2.5 |
C_rD = (1./pr[WHT][CIEY]) * |
332 |
|
|
( pr[WHT][CIEX]*(pr[GRN][CIEY] - pr[BLU][CIEY]) - |
333 |
|
|
pr[WHT][CIEY]*(pr[GRN][CIEX] - pr[BLU][CIEX]) + |
334 |
|
|
pr[GRN][CIEX]*pr[BLU][CIEY] - pr[BLU][CIEX]*pr[GRN][CIEY] ) ; |
335 |
|
|
C_gD = (1./pr[WHT][CIEY]) * |
336 |
|
|
( pr[WHT][CIEX]*(pr[BLU][CIEY] - pr[RED][CIEY]) - |
337 |
|
|
pr[WHT][CIEY]*(pr[BLU][CIEX] - pr[RED][CIEX]) - |
338 |
|
|
pr[RED][CIEX]*pr[BLU][CIEY] + pr[BLU][CIEX]*pr[RED][CIEY] ) ; |
339 |
|
|
C_bD = (1./pr[WHT][CIEY]) * |
340 |
|
|
( pr[WHT][CIEX]*(pr[RED][CIEY] - pr[GRN][CIEY]) - |
341 |
|
|
pr[WHT][CIEY]*(pr[RED][CIEX] - pr[GRN][CIEX]) + |
342 |
|
|
pr[RED][CIEX]*pr[GRN][CIEY] - pr[GRN][CIEX]*pr[RED][CIEY] ) ; |
343 |
|
|
D = pr[RED][CIEX]*(pr[GRN][CIEY] - pr[BLU][CIEY]) + |
344 |
|
|
pr[GRN][CIEX]*(pr[BLU][CIEY] - pr[RED][CIEY]) + |
345 |
|
|
pr[BLU][CIEX]*(pr[RED][CIEY] - pr[GRN][CIEY]) ; |
346 |
greg |
2.15 |
if (CEQ(D,0.)) |
347 |
|
|
return(0); |
348 |
greg |
2.5 |
mat[0][0] = pr[RED][CIEX]*C_rD/D; |
349 |
|
|
mat[0][1] = pr[GRN][CIEX]*C_gD/D; |
350 |
|
|
mat[0][2] = pr[BLU][CIEX]*C_bD/D; |
351 |
|
|
mat[1][0] = pr[RED][CIEY]*C_rD/D; |
352 |
|
|
mat[1][1] = pr[GRN][CIEY]*C_gD/D; |
353 |
|
|
mat[1][2] = pr[BLU][CIEY]*C_bD/D; |
354 |
|
|
mat[2][0] = (1.-pr[RED][CIEX]-pr[RED][CIEY])*C_rD/D; |
355 |
|
|
mat[2][1] = (1.-pr[GRN][CIEX]-pr[GRN][CIEY])*C_gD/D; |
356 |
|
|
mat[2][2] = (1.-pr[BLU][CIEX]-pr[BLU][CIEY])*C_bD/D; |
357 |
greg |
2.15 |
return(1); |
358 |
greg |
2.5 |
} |
359 |
|
|
|
360 |
|
|
|
361 |
greg |
2.15 |
int |
362 |
|
|
comprgb2rgbmat( /* compute conversion from RGB1 to RGB2 */ |
363 |
|
|
COLORMAT mat, |
364 |
|
|
RGBPRIMS pr1, |
365 |
|
|
RGBPRIMS pr2 |
366 |
|
|
) |
367 |
greg |
2.5 |
{ |
368 |
|
|
COLORMAT pr1toxyz, xyztopr2; |
369 |
|
|
|
370 |
greg |
2.6 |
if (pr1 == pr2) { |
371 |
|
|
mat[0][0] = mat[1][1] = mat[2][2] = 1.0; |
372 |
|
|
mat[0][1] = mat[0][2] = mat[1][0] = |
373 |
|
|
mat[1][2] = mat[2][0] = mat[2][1] = 0.0; |
374 |
|
|
return; |
375 |
|
|
} |
376 |
greg |
2.15 |
if (!comprgb2xyzmat(pr1toxyz, pr1)) |
377 |
|
|
return(0); |
378 |
|
|
if (!compxyz2rgbmat(xyztopr2, pr2)) |
379 |
|
|
return(0); |
380 |
greg |
2.5 |
/* combine transforms */ |
381 |
|
|
multcolormat(mat, pr1toxyz, xyztopr2); |
382 |
greg |
2.15 |
return(1); |
383 |
greg |
2.11 |
} |
384 |
|
|
|
385 |
|
|
|
386 |
greg |
2.15 |
int |
387 |
|
|
compxyzWBmat( /* CIE von Kries transform from wht1 to wht2 */ |
388 |
|
|
COLORMAT mat, |
389 |
|
|
float wht1[2], |
390 |
|
|
float wht2[2] |
391 |
|
|
) |
392 |
greg |
2.11 |
{ |
393 |
|
|
COLOR cw1, cw2; |
394 |
|
|
if (XYEQ(wht1,wht2)) { |
395 |
|
|
mat[0][0] = mat[1][1] = mat[2][2] = 1.0; |
396 |
|
|
mat[0][1] = mat[0][2] = mat[1][0] = |
397 |
|
|
mat[1][2] = mat[2][0] = mat[2][1] = 0.0; |
398 |
greg |
2.15 |
return(1); |
399 |
greg |
2.11 |
} |
400 |
greg |
2.15 |
if (CEQ(wht1[CIEX],0.) | CEQ(wht1[CIEY],0.)) |
401 |
|
|
return(0); |
402 |
greg |
2.11 |
cw1[RED] = wht1[CIEX]/wht1[CIEY]; |
403 |
|
|
cw1[GRN] = 1.; |
404 |
|
|
cw1[BLU] = (1. - wht1[CIEX] - wht1[CIEY])/wht1[CIEY]; |
405 |
|
|
colortrans(cw1, vkmat, cw1); |
406 |
greg |
2.15 |
if (CEQ(wht2[CIEX],0.) | CEQ(wht2[CIEY],0.)) |
407 |
|
|
return(0); |
408 |
greg |
2.11 |
cw2[RED] = wht2[CIEX]/wht2[CIEY]; |
409 |
|
|
cw2[GRN] = 1.; |
410 |
|
|
cw2[BLU] = (1. - wht2[CIEX] - wht2[CIEY])/wht2[CIEY]; |
411 |
|
|
colortrans(cw2, vkmat, cw2); |
412 |
greg |
2.15 |
if (CEQ(cw1[RED],0.) | CEQ(cw1[GRN],0.) | CEQ(cw1[BLU],0.)) |
413 |
|
|
return(0); |
414 |
greg |
2.11 |
mat[0][0] = cw2[RED]/cw1[RED]; |
415 |
|
|
mat[1][1] = cw2[GRN]/cw1[GRN]; |
416 |
|
|
mat[2][2] = cw2[BLU]/cw1[BLU]; |
417 |
|
|
mat[0][1] = mat[0][2] = mat[1][0] = |
418 |
|
|
mat[1][2] = mat[2][0] = mat[2][1] = 0.0; |
419 |
|
|
multcolormat(mat, vkmat, mat); |
420 |
|
|
multcolormat(mat, mat, ivkmat); |
421 |
greg |
2.15 |
return(1); |
422 |
greg |
2.11 |
} |
423 |
|
|
|
424 |
|
|
|
425 |
greg |
2.15 |
int |
426 |
|
|
compxyz2rgbWBmat( /* von Kries conversion from CIE to RGB space */ |
427 |
|
|
COLORMAT mat, |
428 |
|
|
RGBPRIMS pr |
429 |
|
|
) |
430 |
greg |
2.11 |
{ |
431 |
|
|
COLORMAT wbmat; |
432 |
|
|
|
433 |
greg |
2.15 |
if (!compxyz2rgbmat(mat, pr)) |
434 |
|
|
return(0); |
435 |
greg |
2.11 |
if (XYEQ(pr[WHT],xyneu)) |
436 |
greg |
2.15 |
return(1); |
437 |
|
|
if (!compxyzWBmat(wbmat, xyneu, pr[WHT])) |
438 |
|
|
return(0); |
439 |
greg |
2.11 |
multcolormat(mat, wbmat, mat); |
440 |
greg |
2.15 |
return(1); |
441 |
greg |
2.11 |
} |
442 |
|
|
|
443 |
greg |
2.15 |
int |
444 |
|
|
comprgb2xyzWBmat( /* von Kries conversion from RGB to CIE space */ |
445 |
|
|
COLORMAT mat, |
446 |
|
|
RGBPRIMS pr |
447 |
|
|
) |
448 |
greg |
2.11 |
{ |
449 |
|
|
COLORMAT wbmat; |
450 |
|
|
|
451 |
greg |
2.15 |
if (!comprgb2xyzmat(mat, pr)) |
452 |
|
|
return(0); |
453 |
greg |
2.11 |
if (XYEQ(pr[WHT],xyneu)) |
454 |
greg |
2.15 |
return(1); |
455 |
|
|
if (!compxyzWBmat(wbmat, pr[WHT], xyneu)) |
456 |
|
|
return(0); |
457 |
greg |
2.11 |
multcolormat(mat, mat, wbmat); |
458 |
greg |
2.15 |
return(1); |
459 |
greg |
2.11 |
} |
460 |
|
|
|
461 |
greg |
2.15 |
int |
462 |
|
|
comprgb2rgbWBmat( /* von Kries conversion from RGB1 to RGB2 */ |
463 |
|
|
COLORMAT mat, |
464 |
|
|
RGBPRIMS pr1, |
465 |
|
|
RGBPRIMS pr2 |
466 |
|
|
) |
467 |
greg |
2.11 |
{ |
468 |
|
|
COLORMAT pr1toxyz, xyztopr2, wbmat; |
469 |
|
|
|
470 |
|
|
if (pr1 == pr2) { |
471 |
|
|
mat[0][0] = mat[1][1] = mat[2][2] = 1.0; |
472 |
|
|
mat[0][1] = mat[0][2] = mat[1][0] = |
473 |
|
|
mat[1][2] = mat[2][0] = mat[2][1] = 0.0; |
474 |
greg |
2.15 |
return(1); |
475 |
greg |
2.11 |
} |
476 |
greg |
2.15 |
if (!comprgb2xyzmat(pr1toxyz, pr1)) |
477 |
|
|
return(0); |
478 |
|
|
if (!compxyzWBmat(wbmat, pr1[WHT], pr2[WHT])) |
479 |
|
|
return(0); |
480 |
|
|
if (!compxyz2rgbmat(xyztopr2, pr2)) |
481 |
|
|
return(0); |
482 |
greg |
2.11 |
/* combine transforms */ |
483 |
|
|
multcolormat(mat, pr1toxyz, wbmat); |
484 |
|
|
multcolormat(mat, mat, xyztopr2); |
485 |
greg |
2.15 |
return(1); |
486 |
greg |
1.1 |
} |