| 1 |
#ifndef lint |
| 2 |
static const char RCSid[] = "$Id: spec_rgb.c,v 2.34 2024/08/14 20:05:23 greg Exp $"; |
| 3 |
#endif |
| 4 |
/* |
| 5 |
* Convert colors and spectral ranges. |
| 6 |
* Added von Kries white-balance calculations 10/01 (GW). |
| 7 |
* |
| 8 |
* Externals declared in color.h |
| 9 |
*/ |
| 10 |
|
| 11 |
#include "copyright.h" |
| 12 |
|
| 13 |
#include <stdio.h> |
| 14 |
#include <string.h> |
| 15 |
#include <math.h> |
| 16 |
#include "color.h" |
| 17 |
|
| 18 |
#define CEPS 1e-4 /* color epsilon */ |
| 19 |
|
| 20 |
#define CEQ(v1,v2) (((v1) <= (v2)+CEPS) & ((v2) <= (v1)+CEPS)) |
| 21 |
|
| 22 |
#define XYEQ(c1,c2) (CEQ((c1)[CIEX],(c2)[CIEX]) & CEQ((c1)[CIEY],(c2)[CIEY])) |
| 23 |
|
| 24 |
|
| 25 |
RGBPRIMS stdprims = STDPRIMS; /* standard primary chromaticities */ |
| 26 |
RGBPRIMS xyzprims = {1,0, 0,1, 0,0, 1.f/3.f,1.f/3.f}; |
| 27 |
|
| 28 |
const COLOR cblack = BLKCOLOR; /* global black color */ |
| 29 |
const COLOR cwhite = WHTCOLOR; /* global white color */ |
| 30 |
const SCOLOR scblack = {0}; /* global black spectrum */ |
| 31 |
|
| 32 |
float xyneu[2] = {1./3., 1./3.}; /* neutral xy chromaticities */ |
| 33 |
|
| 34 |
/* |
| 35 |
* The tables below encode the CIE 1931 2° standard observer |
| 36 |
* functions for X, Y, and Z. These tables are cumulative, as are |
| 37 |
* ones that follow. |
| 38 |
*/ |
| 39 |
|
| 40 |
#define CIE_X_WLMIN 362 |
| 41 |
#define CIE_X_WLMAX 774 |
| 42 |
|
| 43 |
static const unsigned short cie_x_cumul[CIE_X_WLMAX-CIE_X_WLMIN+1] = { |
| 44 |
0,1,1,1,1,1,1,2,2,2,3,3,3,4,5,5,6,7,8,9,10,11,12,14,16,18,20,23,26,29, |
| 45 |
33,37,41,47,53,60,68,77,86,97,108,121,135,151,170,190,214,241,271,304, |
| 46 |
342,385,432,486,545,612,686,768,860,961,1073,1195,1326,1467,1618, |
| 47 |
1776,1943,2117,2298,2485,2677,2875,3076,3281,3489,3700,3912,4125,4340,4555, |
| 48 |
4769,4983,5197,5409,5620,5830,6038,6244,6448,6651,6851,7049,7245,7437, |
| 49 |
7627,7813,7995,8173,8347,8517,8682,8842,8996,9143,9284,9418,9545,9665, |
| 50 |
9778,9884,9984,10077,10164,10245,10321,10390,10454,10513,10566,10615, |
| 51 |
10659,10698,10734,10766,10794,10819,10842,10861,10879,10893,10906,10917, |
| 52 |
10926,10933,10939,10944,10948,10951,10953,10955,10957,10958,10960,10961, |
| 53 |
10964,10967,10971,10977,10984,10994,11006,11020,11038,11060,11085,11114, |
| 54 |
11148,11187,11231,11280,11335,11396,11464,11537,11618,11705,11799,11901, |
| 55 |
12010,12126,12249,12380,12518,12664,12818,12980,13150,13328,13515,13709, |
| 56 |
13913,14124,14345,14574,14813,15060,15317,15582,15858,16142,16437,16741, |
| 57 |
17055,17379,17713,18057,18412,18776,19151,19536,19931,20337,20753,21180, |
| 58 |
21616,22063,22520,22988,23465,23953,24450,24957,25474,26000,26535,27080, |
| 59 |
27633,28195,28765,29343,29929,30522,31122,31729,32342,32961,33585,34215, |
| 60 |
34849,35487,36129,36775,37423,38073,38724,39375,40027,40679,41329,41978, |
| 61 |
42625,43270,43911,44548,45181,45808,46429,47044,47652,48253,48845,49430, |
| 62 |
50005,50571,51128,51674,52209,52733,53245,53745,54232,54706,55167,55614, |
| 63 |
56048,56468,56876,57269,57651,58019,58376,58720,59052,59373,59681,59979, |
| 64 |
60265,60539,60803,61056,61298,61529,61750,61962,62163,62355,62538,62712, |
| 65 |
62877,63034,63183,63325,63459,63586,63706,63820,63927,64028,64123,64213, |
| 66 |
64297,64376,64451,64520,64586,64647,64704,64758,64808,64855,64899,64941, |
| 67 |
64980,65016,65051,65083,65114,65143,65169,65194,65218,65240,65260,65278, |
| 68 |
65296,65312,65327,65341,65354,65366,65377,65387,65397,65406,65415,65423, |
| 69 |
65430,65437,65444,65450,65455,65461,65466,65470,65475,65479,65483,65486, |
| 70 |
65489,65493,65495,65498,65501,65503,65505,65507,65509,65511,65513,65514, |
| 71 |
65516,65517,65518,65519,65520,65521,65522,65523,65524,65525,65526,65526, |
| 72 |
65527,65527,65528,65528,65529,65529,65530,65530,65530,65531,65531,65531, |
| 73 |
65532,65532,65532,65532,65532,65533,65533,65533,65533,65533,65533,65533, |
| 74 |
65533,65534,65534,65534,65534,65534,65534,65534,65534,65534,65534,65534, |
| 75 |
65534,65534,65534,65534,65535 |
| 76 |
}; |
| 77 |
|
| 78 |
#define CIE_Y_WLMIN 386 |
| 79 |
#define CIE_Y_WLMAX 760 |
| 80 |
|
| 81 |
static const unsigned short cie_y_cumul[CIE_Y_WLMAX-CIE_Y_WLMIN+1] = { |
| 82 |
0,1,1,1,1,1,1,1,1,1,2,2,2,2,2,3,3,3,4,4,5,5,6,7,8,8,10,11,12,14, |
| 83 |
15,17,19,22,25,28,31,35,40,45,50,56,63,70,78,86,95,105,115,126, |
| 84 |
138,150,164,178,193,208,225,242,260,280,300,321,343,367,391, |
| 85 |
417,443,472,501,532,564,598,633,670,708,748,790,833,879,926, |
| 86 |
975,1027,1080,1136,1194,1255,1318,1384,1453,1525,1601,1679,1761, |
| 87 |
1846,1935,2027,2123,2223,2327,2435,2548,2665,2787,2915,3048,3187, |
| 88 |
3332,3484,3643,3808,3981,4162,4352,4550,4757,4975,5203,5442,5691, |
| 89 |
5952,6225,6509,6805,7114,7435,7769,8116,8476,8849,9235,9634,10045, |
| 90 |
10469,10904,11351,11808,12275,12752,13239,13734,14239,14752,15273, |
| 91 |
15801,16337,16880,17429,17984,18546,19112,19684,20260,20841,21426, |
| 92 |
22015,22608,23203,23802,24403,25007,25612,26220,26828,27439,28050, |
| 93 |
28662,29275,29888,30501,31114,31727,32340,32951,33561,34170,34777, |
| 94 |
35382,35985,36585,37182,37777,38368,38955,39539,40119,40695,41266, |
| 95 |
41832,42393,42950,43501,44046,44586,45119,45646,46167,46682,47189, |
| 96 |
47690,48183,48670,49149,49621,50085,50542,50991,51432,51866,52293, |
| 97 |
52711,53122,53524,53919,54306,54685,55057,55420,55775,56123,56463, |
| 98 |
56795,57119,57435,57743,58044,58337,58623,58901,59172,59435,59691, |
| 99 |
59939,60180,60414,60640,60859,61070,61274,61471,61661,61844,62019, |
| 100 |
62188,62351,62507,62657,62802,62940,63073,63201,63323,63441,63553, |
| 101 |
63660,63763,63861,63954,64043,64128,64208,64285,64358,64427,64493, |
| 102 |
64555,64614,64670,64723,64773,64820,64865,64907,64947,64984,65019, |
| 103 |
65052,65083,65113,65140,65166,65190,65212,65233,65253,65271,65288, |
| 104 |
65304,65319,65334,65347,65360,65371,65383,65393,65403,65412,65420, |
| 105 |
65428,65435,65442,65449,65454,65460,65465,65470,65474,65478,65482, |
| 106 |
65485,65488,65492,65494,65497,65500,65502,65504,65506,65508,65510, |
| 107 |
65512,65513,65515,65516,65517,65519,65520,65521,65522,65523,65523, |
| 108 |
65524,65525,65526,65526,65527,65527,65528,65528,65529,65529,65530, |
| 109 |
65530,65530,65531,65531,65531,65532,65532,65532,65532,65532,65533, |
| 110 |
65533,65533,65533,65533,65533,65533,65534,65534,65534,65534,65534, |
| 111 |
65534,65534,65534,65534,65534,65534,65534,65534,65534,65534,65534,65535 |
| 112 |
}; |
| 113 |
|
| 114 |
#define CIE_Z_WLMIN 359 |
| 115 |
#define CIE_Z_WLMAX 624 |
| 116 |
|
| 117 |
static const unsigned short cie_z_cumul[CIE_Z_WLMAX-CIE_Z_WLMIN+1] = { |
| 118 |
0,1,1,2,2,3,4,5,6,7,8,9,11,12,14,16,19,22,25,28,32,37,41,47,52,59,66,75,84, |
| 119 |
95,107,121,136,154,173,196,221,250,283,321,362,408,458,512,573,640,717,804, |
| 120 |
903,1015,1142,1285,1446,1627,1830,2058,2313,2598,2917,3272,3668,4108,4597, |
| 121 |
5135,5723,6360,7044,7773,8544,9356,10205,11090,12006,12952,13923,14918, |
| 122 |
15934,16967,18016,19076,20148,21227,22312,23401,24492,25585,26678,27771, |
| 123 |
28861,29950,31037,32121,33202,34281,35355,36424,37487,38542,39588,40624, |
| 124 |
41647,42657,43652,44631,45590,46527,47438,48321,49173,49993,50783,51542, |
| 125 |
52270,52968,53636,54275,54885,55465,56018,56543,57042,57514,57961,58384, |
| 126 |
58784,59162,59519,59856,60175,60477,60762,61032,61287,61529,61757,61974, |
| 127 |
62179,62374,62559,62734,62901,63059,63211,63355,63492,63622,63745,63862, |
| 128 |
63971,64075,64172,64263,64347,64427,64500,64569,64632,64692,64747,64798, |
| 129 |
64846,64891,64933,64973,65010,65045,65078,65109,65139,65166,65192,65216, |
| 130 |
65239,65260,65280,65298,65315,65331,65345,65359,65371,65383,65393,65403, |
| 131 |
65412,65420,65428,65435,65441,65447,65452,65457,65462,65466,65470,65473, |
| 132 |
65476,65479,65482,65485,65487,65489,65491,65493,65495,65497,65498,65500, |
| 133 |
65501,65503,65504,65505,65506,65508,65509,65510,65511,65512,65513,65514, |
| 134 |
65515,65516,65517,65518,65519,65520,65520,65521,65522,65523,65523,65524, |
| 135 |
65525,65525,65526,65527,65527,65528,65528,65529,65529,65530,65530,65531, |
| 136 |
65531,65531,65532,65532,65532,65532,65533,65533,65533,65533,65533,65533, |
| 137 |
65534,65534,65534,65534,65534,65534,65534,65534,65534,65535 |
| 138 |
}; |
| 139 |
|
| 140 |
#define SCOTOPIC_WLMIN 382 |
| 141 |
#define SCOTOPIC_WLMAX 684 |
| 142 |
|
| 143 |
static const unsigned short scotopic_cumul[SCOTOPIC_WLMAX-SCOTOPIC_WLMIN+1] = { |
| 144 |
0, 1, 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 15, 17, 20, 24, 28, 33, 38, 44, |
| 145 |
52, 60, 69, 80, 93, 107, 123, 142, 163, 186, 213, 242, 275, 312, 353, |
| 146 |
398, 448, 502, 562, 627, 698, 775, 859, 949, 1046, 1150, 1261, 1380, |
| 147 |
1507, 1642, 1785, 1936, 2096, 2265, 2442, 2628, 2823, 3027, 3239, 3461, |
| 148 |
3691, 3930, 4178, 4435, 4700, 4974, 5257, 5548, 5847, 6154, 6469, 6793, |
| 149 |
7123, 7462, 7809, 8162, 8524, 8892, 9268, 9651, 10041, 10438, 10843, 11254, |
| 150 |
11673, 12099, 12532, 12973, 13422, 13878, 14342, 14814, 15293, 15780, 16276, |
| 151 |
16779, 17290, 17809, 18336, 18872, 19415, 19967, 20526, 21093, 21667, 22249, |
| 152 |
22839, 23436, 24039, 24649, 25266, 25890, 26519, 27154, 27795, 28441, 29092, |
| 153 |
29747, 30405, 31068, 31734, 32402, 33074, 33747, 34420, 35095, 35771, 36446, |
| 154 |
37119, 37793, 38464, 39132, 39798, 40460, 41118, 41772, 42421, 43064, 43701, |
| 155 |
44332, 44957, 45575, 46185, 46787, 47381, 47967, 48543, 49110, 49668, 50215, |
| 156 |
50753, 51280, 51797, 52302, 52797, 53281, 53754, 54215, 54665, 55104, 55531, |
| 157 |
55947, 56352, 56744, 57125, 57495, 57853, 58200, 58536, 58860, 59174, 59477, |
| 158 |
59769, 60051, 60322, 60583, 60834, 61075, 61306, 61528, 61741, 61944, 62139, |
| 159 |
62326, 62504, 62674, 62836, 62991, 63138, 63278, 63412, 63538, 63659, 63773, |
| 160 |
63881, 63983, 64080, 64172, 64259, 64340, 64418, 64490, 64559, 64623, 64684, |
| 161 |
64742, 64795, 64846, 64893, 64937, 64978, 65017, 65053, 65087, 65119, 65149, |
| 162 |
65176, 65202, 65226, 65248, 65269, 65289, 65307, 65323, 65339, 65353, 65367, |
| 163 |
65379, 65391, 65402, 65412, 65421, 65430, 65438, 65445, 65452, 65458, 65464, |
| 164 |
65469, 65474, 65479, 65483, 65487, 65491, 65494, 65497, 65500, 65503, 65505, |
| 165 |
65507, 65509, 65511, 65513, 65514, 65516, 65517, 65519, 65520, 65521, 65522, |
| 166 |
65523, 65524, 65525, 65525, 65526, 65527, 65527, 65528, 65528, 65529, 65529, |
| 167 |
65529, 65530, 65530, 65530, 65531, 65531, 65531, 65531, 65532, 65532, 65532, |
| 168 |
65532, 65532, 65533, 65533, 65533, 65533, 65533, 65533, 65533, 65533, 65533, |
| 169 |
65533, 65534, 65534, 65534, 65534, 65534, 65534, 65534, 65534, 65535 |
| 170 |
}; |
| 171 |
|
| 172 |
#define MELANOPIC_WLMIN 380 |
| 173 |
#define MELANOPIC_WLMAX 651 |
| 174 |
|
| 175 |
static const unsigned short melanopic_cumul[MELANOPIC_WLMAX-MELANOPIC_WLMIN+1] = { |
| 176 |
0, 1, 2, 3, 4, 5, 7, 8, 10, 12, 14, 17, 20, 23, 27, 32, 37, 42, 49, 56, |
| 177 |
65, 75, 86, 99, 114, 131, 150, 173, 200, 230, 265, 303, 347, 395, 448, |
| 178 |
508, 574, 650, 734, 828, 931, 1041, 1158, 1283, 1415, 1554, 1703, 1862, |
| 179 |
2031, 2211, 2400, 2600, 2809, 3028, 3257, 3497, 3748, 4012, 4288, 4576, |
| 180 |
4876, 5187, 5509, 5842, 6185, 6540, 6905, 7283, 7673, 8075, 8489, 8915, |
| 181 |
9351, 9799, 10259, 10729, 11211, 11705, 12211, 12729, 13258, 13799, |
| 182 |
14351, 14915, 15491, 16078, 16676, 17286, 17908, 18541, 19184, 19837, |
| 183 |
20498, 21168, 21846, 22532, 23226, 23928, 24637, 25353, 26075, 26802, |
| 184 |
27532, 28267, 29005, 29746, 30488, 31233, 31979, 32726, 33473, 34220, |
| 185 |
34966, 35711, 36455, 37196, 37935, 38671, 39403, 40129, 40851, 41568, |
| 186 |
42279, 42983, 43680, 44369, 45050, 45724, 46388, 47043, 47688, 48322, |
| 187 |
48945, 49557, 50156, 50743, 51317, 51879, 52428, 52964, 53487, 53997, |
| 188 |
54493, 54976, 55445, 55901, 56343, 56771, 57186, 57587, 57976, 58351, |
| 189 |
58712, 59061, 59397, 59720, 60031, 60330, 60616, 60891, 61154, 61405, |
| 190 |
61646, 61875, 62094, 62303, 62501, 62690, 62870, 63040, 63201, 63354, |
| 191 |
63498, 63634, 63763, 63884, 63998, 64105, 64206, 64300, 64389, 64472, |
| 192 |
64549, 64622, 64689, 64753, 64811, 64866, 64917, 64964, 65008, 65049, |
| 193 |
65086, 65121, 65154, 65184, 65211, 65237, 65260, 65282, 65302, 65321, |
| 194 |
65338, 65354, 65368, 65381, 65394, 65405, 65415, 65425, 65434, 65442, |
| 195 |
65449, 65456, 65463, 65468, 65474, 65479, 65483, 65487, 65491, 65494, |
| 196 |
65498, 65501, 65503, 65506, 65508, 65510, 65512, 65514, 65515, 65517, |
| 197 |
65518, 65520, 65521, 65522, 65523, 65524, 65525, 65525, 65526, 65527, |
| 198 |
65527, 65528, 65528, 65529, 65529, 65530, 65530, 65530, 65531, 65531, |
| 199 |
65531, 65531, 65532, 65532, 65532, 65532, 65532, 65533, 65533, 65533, |
| 200 |
65533, 65533, 65533, 65533, 65533, 65533, 65534, 65534, 65534, 65535 |
| 201 |
}; |
| 202 |
|
| 203 |
COLORMAT xyz2rgbmat = { /* XYZ to RGB (no white balance) */ |
| 204 |
{(CIE_y_g - CIE_y_b - CIE_x_b*CIE_y_g + CIE_y_b*CIE_x_g)/CIE_C_rD, |
| 205 |
(CIE_x_b - CIE_x_g - CIE_x_b*CIE_y_g + CIE_x_g*CIE_y_b)/CIE_C_rD, |
| 206 |
(CIE_x_g*CIE_y_b - CIE_x_b*CIE_y_g)/CIE_C_rD}, |
| 207 |
{(CIE_y_b - CIE_y_r - CIE_y_b*CIE_x_r + CIE_y_r*CIE_x_b)/CIE_C_gD, |
| 208 |
(CIE_x_r - CIE_x_b - CIE_x_r*CIE_y_b + CIE_x_b*CIE_y_r)/CIE_C_gD, |
| 209 |
(CIE_x_b*CIE_y_r - CIE_x_r*CIE_y_b)/CIE_C_gD}, |
| 210 |
{(CIE_y_r - CIE_y_g - CIE_y_r*CIE_x_g + CIE_y_g*CIE_x_r)/CIE_C_bD, |
| 211 |
(CIE_x_g - CIE_x_r - CIE_x_g*CIE_y_r + CIE_x_r*CIE_y_g)/CIE_C_bD, |
| 212 |
(CIE_x_r*CIE_y_g - CIE_x_g*CIE_y_r)/CIE_C_bD} |
| 213 |
}; |
| 214 |
|
| 215 |
COLORMAT rgb2xyzmat = { /* RGB to XYZ (no white balance) */ |
| 216 |
{CIE_x_r*CIE_C_rD/CIE_D,CIE_x_g*CIE_C_gD/CIE_D,CIE_x_b*CIE_C_bD/CIE_D}, |
| 217 |
{CIE_y_r*CIE_C_rD/CIE_D,CIE_y_g*CIE_C_gD/CIE_D,CIE_y_b*CIE_C_bD/CIE_D}, |
| 218 |
{(1.-CIE_x_r-CIE_y_r)*CIE_C_rD/CIE_D, |
| 219 |
(1.-CIE_x_g-CIE_y_g)*CIE_C_gD/CIE_D, |
| 220 |
(1.-CIE_x_b-CIE_y_b)*CIE_C_bD/CIE_D} |
| 221 |
}; |
| 222 |
|
| 223 |
COLORMAT vkmat = { /* Sharp primary matrix */ |
| 224 |
{ 1.2694, -0.0988, -0.1706}, |
| 225 |
{-0.8364, 1.8006, 0.0357}, |
| 226 |
{ 0.0297, -0.0315, 1.0018} |
| 227 |
}; |
| 228 |
|
| 229 |
COLORMAT ivkmat = { /* inverse Sharp primary matrix */ |
| 230 |
{ 0.8156, 0.0472, 0.1372}, |
| 231 |
{ 0.3791, 0.5769, 0.0440}, |
| 232 |
{-0.0123, 0.0167, 0.9955} |
| 233 |
}; |
| 234 |
|
| 235 |
|
| 236 |
void |
| 237 |
spec_cie( /* compute XYZ color from a spectral range */ |
| 238 |
COLOR col, /* returned color */ |
| 239 |
int s, /* starting and ending wavelengths */ |
| 240 |
int e |
| 241 |
) |
| 242 |
{ |
| 243 |
if (s > e) { int i = s; s = e; e = i; } |
| 244 |
|
| 245 |
if ((s >= CIE_X_WLMAX) | (e <= CIE_X_WLMIN)) |
| 246 |
col[CIEX] = 0; |
| 247 |
else |
| 248 |
col[CIEX] = (cie_x_cumul[e>=CIE_X_WLMAX ? CIE_X_WLMAX-CIE_X_WLMIN : e-CIE_X_WLMIN] - |
| 249 |
cie_x_cumul[(s>CIE_X_WLMIN)*(s-CIE_X_WLMIN)])*(1./65535.); |
| 250 |
|
| 251 |
if ((s >= CIE_Y_WLMAX) | (e <= CIE_Y_WLMIN)) |
| 252 |
col[CIEY] = 0; |
| 253 |
else |
| 254 |
col[CIEY] = (cie_y_cumul[e>=CIE_Y_WLMAX ? CIE_Y_WLMAX-CIE_Y_WLMIN : e-CIE_Y_WLMIN] - |
| 255 |
cie_y_cumul[(s>CIE_Y_WLMIN)*(s-CIE_Y_WLMIN)])*(1./65535.); |
| 256 |
|
| 257 |
if ((s >= CIE_Z_WLMAX) | (e <= CIE_Z_WLMIN)) |
| 258 |
col[CIEZ] = 0; |
| 259 |
else |
| 260 |
col[CIEZ] = (cie_z_cumul[e>=CIE_Z_WLMAX ? CIE_Z_WLMAX-CIE_Z_WLMIN : e-CIE_Z_WLMIN] - |
| 261 |
cie_z_cumul[(s>CIE_Z_WLMIN)*(s-CIE_Z_WLMIN)])*(1./65535.); |
| 262 |
} |
| 263 |
|
| 264 |
|
| 265 |
void |
| 266 |
spec_rgb( /* compute RGB color from spectral range */ |
| 267 |
COLOR col, |
| 268 |
int s, |
| 269 |
int e |
| 270 |
) |
| 271 |
{ |
| 272 |
COLOR ciecolor; |
| 273 |
|
| 274 |
spec_cie(ciecolor, s, e); |
| 275 |
colortrans(col, xyz2rgbmat, ciecolor); |
| 276 |
} |
| 277 |
|
| 278 |
|
| 279 |
static double |
| 280 |
spec_dot( /* spectrum dot-product with cumulative observer */ |
| 281 |
const SCOLOR scol, |
| 282 |
int ncs, |
| 283 |
const float wlpt[4], |
| 284 |
const unsigned short cumul[], |
| 285 |
int wlmin, |
| 286 |
int wlmax |
| 287 |
) |
| 288 |
{ |
| 289 |
const double wlstp = (wlpt[0] - wlpt[3])/(double)ncs; |
| 290 |
int wl1 = (int)wlpt[3]; |
| 291 |
int n = 0; |
| 292 |
double sum = 0; |
| 293 |
|
| 294 |
if (wl1 < wlmin) { |
| 295 |
n += (int)((wlmin - wl1)/wlstp); |
| 296 |
wl1 = wlmin; |
| 297 |
} else if (wl1 >= wlmax) |
| 298 |
return(.0); |
| 299 |
|
| 300 |
while (n < ncs) { |
| 301 |
int wl0 = wl1; |
| 302 |
wl1 = (int)(ncs==3 ? wlpt[2-n] : wlpt[3] + (n+1)*wlstp); |
| 303 |
if (wl1 >= wlmax) { |
| 304 |
sum += (65535 - cumul[wl0-wlmin]) * scol[ncs-1-n]; |
| 305 |
break; |
| 306 |
} |
| 307 |
sum += (cumul[wl1-wlmin] - cumul[wl0-wlmin]) * scol[ncs-1-n++]; |
| 308 |
} |
| 309 |
return(sum * (1./65535.)); |
| 310 |
} |
| 311 |
|
| 312 |
|
| 313 |
void |
| 314 |
scolor2cie( /* accurate conversion from spectrum to XYZ */ |
| 315 |
COLOR col, |
| 316 |
const SCOLOR scol, |
| 317 |
int ncs, |
| 318 |
const float wlpt[4] |
| 319 |
) |
| 320 |
{ |
| 321 |
if (ncs == 3) { /* not a spectrum! */ |
| 322 |
rgb_cie(col, scol); |
| 323 |
return; |
| 324 |
} |
| 325 |
col[CIEX] = spec_dot(scol, ncs, wlpt, cie_x_cumul, CIE_X_WLMIN, CIE_X_WLMAX); |
| 326 |
col[CIEY] = spec_dot(scol, ncs, wlpt, cie_y_cumul, CIE_Y_WLMIN, CIE_Y_WLMAX); |
| 327 |
col[CIEZ] = spec_dot(scol, ncs, wlpt, cie_z_cumul, CIE_Z_WLMIN, CIE_Z_WLMAX); |
| 328 |
} |
| 329 |
|
| 330 |
|
| 331 |
void |
| 332 |
scolor2rgb( /* accurate conversion from spectrum to RGB */ |
| 333 |
COLOR col, |
| 334 |
const SCOLOR scol, |
| 335 |
int ncs, |
| 336 |
const float wlpt[4] |
| 337 |
) |
| 338 |
{ |
| 339 |
COLOR ciecolor; |
| 340 |
|
| 341 |
if (ncs == 3) { /* not really a spectrum, so we punt... */ |
| 342 |
copycolor(col, scol); |
| 343 |
return; |
| 344 |
} |
| 345 |
scolor2cie(ciecolor, scol, ncs, wlpt); |
| 346 |
cie_rgb(col, ciecolor); |
| 347 |
} |
| 348 |
|
| 349 |
|
| 350 |
void |
| 351 |
scolor_out( /* prepare (spectral) color for output */ |
| 352 |
COLORV *cout, |
| 353 |
RGBPRIMS pr, |
| 354 |
const SCOLOR cres |
| 355 |
) |
| 356 |
{ |
| 357 |
static COLORMAT xyz2myp; |
| 358 |
static RGBPRIMP lastp = NULL; |
| 359 |
|
| 360 |
if (!pr) { /* output is spectral */ |
| 361 |
copyscolor(cout, cres); |
| 362 |
} else if (pr == stdprims) { /* output is standard RGB */ |
| 363 |
scolor_rgb(cout, cres); |
| 364 |
} else if (pr == xyzprims) { /* output is XYZ */ |
| 365 |
scolor_cie(cout, cres); |
| 366 |
scalecolor(cout, WHTEFFICACY); |
| 367 |
} else if (NCSAMP > 3) { /* spectral -> custom RGB */ |
| 368 |
COLOR xyz; |
| 369 |
if (lastp != pr) |
| 370 |
compxyz2rgbWBmat(xyz2myp, lastp=pr); |
| 371 |
scolor_cie(xyz, cres); |
| 372 |
colortrans(cout, xyz2myp, xyz); |
| 373 |
clipgamut(cout, xyz[CIEY], CGAMUT_LOWER, cblack, cwhite); |
| 374 |
} else { /* else copy unknown RGB */ |
| 375 |
copycolor(cout, cres); |
| 376 |
} |
| 377 |
} |
| 378 |
|
| 379 |
|
| 380 |
double |
| 381 |
scolor2photopic( /* compute scotopic integral for spectral color */ |
| 382 |
const SCOLOR scol, |
| 383 |
int ncs, |
| 384 |
const float wlpt[4] |
| 385 |
) |
| 386 |
{ |
| 387 |
if (ncs == 3) |
| 388 |
return bright(scol); |
| 389 |
|
| 390 |
return(spec_dot(scol, ncs, wlpt, cie_y_cumul, CIE_Y_WLMIN, CIE_Y_WLMAX)); |
| 391 |
} |
| 392 |
|
| 393 |
|
| 394 |
double |
| 395 |
scolor2scotopic( /* compute Y channel for spectral color */ |
| 396 |
const SCOLOR scol, |
| 397 |
int ncs, |
| 398 |
const float wlpt[4] |
| 399 |
) |
| 400 |
{ |
| 401 |
return(spec_dot(scol, ncs, wlpt, scotopic_cumul, SCOTOPIC_WLMIN, SCOTOPIC_WLMAX)); |
| 402 |
} |
| 403 |
|
| 404 |
|
| 405 |
double |
| 406 |
scolor2melanopic( /* compute melanopic integral for spectral color */ |
| 407 |
const SCOLOR scol, |
| 408 |
int ncs, |
| 409 |
const float wlpt[4] |
| 410 |
) |
| 411 |
{ |
| 412 |
return(spec_dot(scol, ncs, wlpt, melanopic_cumul, MELANOPIC_WLMIN, MELANOPIC_WLMAX)); |
| 413 |
} |
| 414 |
|
| 415 |
|
| 416 |
double |
| 417 |
scolor_photopic( /* compute scotopic integral for spectral color */ |
| 418 |
const SCOLOR scol |
| 419 |
) |
| 420 |
{ |
| 421 |
return(scolor2photopic(scol, NCSAMP, WLPART)); |
| 422 |
} |
| 423 |
|
| 424 |
|
| 425 |
double |
| 426 |
scolor_scotopic( /* compute Y channel for spectral color */ |
| 427 |
const SCOLOR scol |
| 428 |
) |
| 429 |
{ |
| 430 |
return(scolor2scotopic(scol, NCSAMP, WLPART)); |
| 431 |
} |
| 432 |
|
| 433 |
|
| 434 |
double |
| 435 |
scolor_melanopic( /* compute melanopic integral for spectral color */ |
| 436 |
const SCOLOR scol |
| 437 |
) |
| 438 |
{ |
| 439 |
return(scolor2melanopic(scol, NCSAMP, WLPART)); |
| 440 |
} |
| 441 |
|
| 442 |
|
| 443 |
void |
| 444 |
convertscolorcol( /* any uniform spectrum to working */ |
| 445 |
SCOLOR rcol, |
| 446 |
const COLORV src[], |
| 447 |
int snc, |
| 448 |
double swl0, |
| 449 |
double swl1 |
| 450 |
) |
| 451 |
{ |
| 452 |
if (NCSAMP > 3) { /* spectrum -> spectrum */ |
| 453 |
convertscolor(rcol, NCSAMP, WLPART[0], WLPART[3], |
| 454 |
src, snc, swl0, swl1); |
| 455 |
} else if ((snc <= MAXCSAMP) & (swl0 > swl1)) { |
| 456 |
float wlpt[4]; /* no intermediate conversion needed */ |
| 457 |
wlpt[0] = swl0; wlpt[3] = swl1; |
| 458 |
wlpt[1] = WLPART[1]; wlpt[2] = WLPART[2]; |
| 459 |
scolor2rgb(rcol, (COLORV *)src, snc, wlpt); |
| 460 |
} else { |
| 461 |
SCOLOR dcol; /* else convert spectrum first */ |
| 462 |
int dnc = snc*(WLPART[0] - WLPART[3])/fabs(swl0 - swl1) + .99; |
| 463 |
if (dnc > MAXCSAMP) dnc = MAXCSAMP; |
| 464 |
convertscolor(dcol, dnc, WLPART[0], WLPART[3], src, snc, swl0, swl1); |
| 465 |
scolor2rgb(rcol, dcol, dnc, WLPART); |
| 466 |
} |
| 467 |
} |
| 468 |
|
| 469 |
|
| 470 |
void |
| 471 |
cie_rgb( /* convert CIE color to standard RGB */ |
| 472 |
COLOR rgb, |
| 473 |
const COLOR xyz |
| 474 |
) |
| 475 |
{ |
| 476 |
colortrans(rgb, xyz2rgbmat, xyz); |
| 477 |
clipgamut(rgb, xyz[CIEY], CGAMUT_LOWER, cblack, cwhite); |
| 478 |
} |
| 479 |
|
| 480 |
|
| 481 |
int |
| 482 |
clipgamut( /* clip to gamut cube */ |
| 483 |
COLOR col, |
| 484 |
double brt, |
| 485 |
int gamut, |
| 486 |
const COLOR lower, |
| 487 |
const COLOR upper |
| 488 |
) |
| 489 |
{ |
| 490 |
int rflags = 0; |
| 491 |
double brtmin, brtmax, v, vv; |
| 492 |
COLOR cgry; |
| 493 |
int i; |
| 494 |
/* check for no check */ |
| 495 |
if (gamut == 0) return(0); |
| 496 |
/* check brightness limits */ |
| 497 |
brtmin = 1./3.*(lower[0]+lower[1]+lower[2]); |
| 498 |
if (gamut & CGAMUT_LOWER && brt < brtmin) { |
| 499 |
copycolor(col, lower); |
| 500 |
return(CGAMUT_LOWER); |
| 501 |
} |
| 502 |
brtmax = 1./3.*(upper[0]+upper[1]+upper[2]); |
| 503 |
if (gamut & CGAMUT_UPPER && brt > brtmax) { |
| 504 |
copycolor(col, upper); |
| 505 |
return(CGAMUT_UPPER); |
| 506 |
} |
| 507 |
/* compute equivalent grey */ |
| 508 |
v = (brt - brtmin)/(brtmax - brtmin); |
| 509 |
for (i = 0; i < 3; i++) |
| 510 |
cgry[i] = v*upper[i] + (1.-v)*lower[i]; |
| 511 |
vv = 1.; /* check each limit */ |
| 512 |
for (i = 0; i < 3; i++) |
| 513 |
if (gamut & CGAMUT_LOWER && col[i] < lower[i]) { |
| 514 |
v = (lower[i] - cgry[i])/(col[i] - cgry[i]); |
| 515 |
if (v < vv) vv = v; |
| 516 |
rflags |= CGAMUT_LOWER; |
| 517 |
} else if (gamut & CGAMUT_UPPER && col[i] > upper[i]) { |
| 518 |
v = (upper[i] - cgry[i])/(col[i] - cgry[i]); |
| 519 |
if (v < vv) vv = v; |
| 520 |
rflags |= CGAMUT_UPPER; |
| 521 |
} |
| 522 |
if (rflags) /* desaturate to cube face */ |
| 523 |
for (i = 0; i < 3; i++) |
| 524 |
col[i] = vv*col[i] + (1.-vv)*cgry[i]; |
| 525 |
return(rflags); |
| 526 |
} |
| 527 |
|
| 528 |
|
| 529 |
void |
| 530 |
colortrans( /* convert c1 by mat and put into c2 */ |
| 531 |
COLOR c2, |
| 532 |
const COLORMAT mat, |
| 533 |
const COLOR c1 |
| 534 |
) |
| 535 |
{ |
| 536 |
COLOR cout; |
| 537 |
|
| 538 |
cout[0] = mat[0][0]*c1[0] + mat[0][1]*c1[1] + mat[0][2]*c1[2]; |
| 539 |
cout[1] = mat[1][0]*c1[0] + mat[1][1]*c1[1] + mat[1][2]*c1[2]; |
| 540 |
cout[2] = mat[2][0]*c1[0] + mat[2][1]*c1[1] + mat[2][2]*c1[2]; |
| 541 |
|
| 542 |
copycolor(c2, cout); |
| 543 |
} |
| 544 |
|
| 545 |
|
| 546 |
void |
| 547 |
multcolormat( /* multiply m1 by m2 and put into m3 */ |
| 548 |
COLORMAT m3, /* m3 can be either m1 or m2 w/o harm */ |
| 549 |
const COLORMAT m2, |
| 550 |
const COLORMAT m1 |
| 551 |
) |
| 552 |
{ |
| 553 |
COLORMAT mt; |
| 554 |
int i, j; |
| 555 |
|
| 556 |
for (i = 0; i < 3; i++) |
| 557 |
for (j = 0; j < 3; j++) |
| 558 |
mt[i][j] = m1[i][0]*m2[0][j] + |
| 559 |
m1[i][1]*m2[1][j] + |
| 560 |
m1[i][2]*m2[2][j] ; |
| 561 |
cpcolormat(m3, mt); |
| 562 |
} |
| 563 |
|
| 564 |
|
| 565 |
int |
| 566 |
colorprimsOK( /* are color primaries reasonable? */ |
| 567 |
RGBPRIMS pr |
| 568 |
) |
| 569 |
{ |
| 570 |
int i, j; |
| 571 |
/* check white point */ |
| 572 |
if ((pr[3][CIEX] <= CEPS) | (pr[3][CIEX] >= 1.-CEPS) | |
| 573 |
(pr[3][CIEY] <= CEPS) | (pr[3][CIEY] >= 1.-CEPS)) |
| 574 |
return(0); |
| 575 |
for (i = 3; i--; ) /* check for XYZ color primaries */ |
| 576 |
if (!CEQ(pr[i][CIEX],(i==0)) | !CEQ(pr[i][CIEY],(i==1))) |
| 577 |
break; |
| 578 |
if (i < 0) |
| 579 |
return(-1); /* flag as XYZ color space */ |
| 580 |
/* check color primaries */ |
| 581 |
for (i = 0; i < 3; i++) { |
| 582 |
if ((pr[i][CIEX] <= -2.) | (pr[i][CIEY] <= -2.)) |
| 583 |
return(0); |
| 584 |
if ((pr[i][CIEX] >= 3.) | (pr[i][CIEY] >= 3.)) |
| 585 |
return(0); |
| 586 |
if (pr[i][CIEX] + pr[i][CIEY] <= -2.) |
| 587 |
return(0); |
| 588 |
if (pr[i][CIEX] + pr[i][CIEY] >= 3.) |
| 589 |
return(0); |
| 590 |
} |
| 591 |
for (i = 0; i < 4; i++) /* make sure space is 3-dimensional */ |
| 592 |
for (j = i+1; j < 4; j++) |
| 593 |
if (CEQ(pr[i][CIEX],pr[j][CIEX]) & |
| 594 |
CEQ(pr[i][CIEY],pr[j][CIEY])) |
| 595 |
return(0); |
| 596 |
return(1); |
| 597 |
} |
| 598 |
|
| 599 |
|
| 600 |
|
| 601 |
int |
| 602 |
compxyz2rgbmat( /* compute conversion from CIE to RGB space */ |
| 603 |
COLORMAT mat, |
| 604 |
RGBPRIMS pr |
| 605 |
) |
| 606 |
{ |
| 607 |
double C_rD, C_gD, C_bD; |
| 608 |
|
| 609 |
if (pr == stdprims) { /* can use xyz2rgbmat */ |
| 610 |
cpcolormat(mat, xyz2rgbmat); |
| 611 |
return(1); |
| 612 |
} |
| 613 |
if (pr == xyzprims) { /* identity */ |
| 614 |
memset(mat, 0, sizeof(COLORMAT)); |
| 615 |
mat[0][0] = mat[1][1] = mat[2][2] = 1.f; |
| 616 |
return(1); |
| 617 |
} |
| 618 |
if (CEQ(pr[WHT][CIEX],0.) | CEQ(pr[WHT][CIEY],0.)) |
| 619 |
return(0); |
| 620 |
C_rD = (1./pr[WHT][CIEY]) * |
| 621 |
( pr[WHT][CIEX]*(pr[GRN][CIEY] - pr[BLU][CIEY]) - |
| 622 |
pr[WHT][CIEY]*(pr[GRN][CIEX] - pr[BLU][CIEX]) + |
| 623 |
pr[GRN][CIEX]*pr[BLU][CIEY] - pr[BLU][CIEX]*pr[GRN][CIEY] ) ; |
| 624 |
if (CEQ(C_rD,0.)) |
| 625 |
return(0); |
| 626 |
C_gD = (1./pr[WHT][CIEY]) * |
| 627 |
( pr[WHT][CIEX]*(pr[BLU][CIEY] - pr[RED][CIEY]) - |
| 628 |
pr[WHT][CIEY]*(pr[BLU][CIEX] - pr[RED][CIEX]) - |
| 629 |
pr[RED][CIEX]*pr[BLU][CIEY] + pr[BLU][CIEX]*pr[RED][CIEY] ) ; |
| 630 |
if (CEQ(C_gD,0.)) |
| 631 |
return(0); |
| 632 |
C_bD = (1./pr[WHT][CIEY]) * |
| 633 |
( pr[WHT][CIEX]*(pr[RED][CIEY] - pr[GRN][CIEY]) - |
| 634 |
pr[WHT][CIEY]*(pr[RED][CIEX] - pr[GRN][CIEX]) + |
| 635 |
pr[RED][CIEX]*pr[GRN][CIEY] - pr[GRN][CIEX]*pr[RED][CIEY] ) ; |
| 636 |
if (CEQ(C_bD,0.)) |
| 637 |
return(0); |
| 638 |
mat[0][0] = (pr[GRN][CIEY] - pr[BLU][CIEY] - |
| 639 |
pr[BLU][CIEX]*pr[GRN][CIEY] + |
| 640 |
pr[BLU][CIEY]*pr[GRN][CIEX])/C_rD ; |
| 641 |
mat[0][1] = (pr[BLU][CIEX] - pr[GRN][CIEX] - |
| 642 |
pr[BLU][CIEX]*pr[GRN][CIEY] + |
| 643 |
pr[GRN][CIEX]*pr[BLU][CIEY])/C_rD ; |
| 644 |
mat[0][2] = (pr[GRN][CIEX]*pr[BLU][CIEY] - |
| 645 |
pr[BLU][CIEX]*pr[GRN][CIEY])/C_rD ; |
| 646 |
mat[1][0] = (pr[BLU][CIEY] - pr[RED][CIEY] - |
| 647 |
pr[BLU][CIEY]*pr[RED][CIEX] + |
| 648 |
pr[RED][CIEY]*pr[BLU][CIEX])/C_gD ; |
| 649 |
mat[1][1] = (pr[RED][CIEX] - pr[BLU][CIEX] - |
| 650 |
pr[RED][CIEX]*pr[BLU][CIEY] + |
| 651 |
pr[BLU][CIEX]*pr[RED][CIEY])/C_gD ; |
| 652 |
mat[1][2] = (pr[BLU][CIEX]*pr[RED][CIEY] - |
| 653 |
pr[RED][CIEX]*pr[BLU][CIEY])/C_gD ; |
| 654 |
mat[2][0] = (pr[RED][CIEY] - pr[GRN][CIEY] - |
| 655 |
pr[RED][CIEY]*pr[GRN][CIEX] + |
| 656 |
pr[GRN][CIEY]*pr[RED][CIEX])/C_bD ; |
| 657 |
mat[2][1] = (pr[GRN][CIEX] - pr[RED][CIEX] - |
| 658 |
pr[GRN][CIEX]*pr[RED][CIEY] + |
| 659 |
pr[RED][CIEX]*pr[GRN][CIEY])/C_bD ; |
| 660 |
mat[2][2] = (pr[RED][CIEX]*pr[GRN][CIEY] - |
| 661 |
pr[GRN][CIEX]*pr[RED][CIEY])/C_bD ; |
| 662 |
return(1); |
| 663 |
} |
| 664 |
|
| 665 |
|
| 666 |
int |
| 667 |
comprgb2xyzmat( /* compute conversion from RGB to CIE space */ |
| 668 |
COLORMAT mat, |
| 669 |
RGBPRIMS pr |
| 670 |
) |
| 671 |
{ |
| 672 |
double C_rD, C_gD, C_bD, D; |
| 673 |
|
| 674 |
if (pr == stdprims) { /* can use rgb2xyzmat */ |
| 675 |
cpcolormat(mat, rgb2xyzmat); |
| 676 |
return(1); |
| 677 |
} |
| 678 |
if (pr == xyzprims) { /* identity */ |
| 679 |
memset(mat, 0, sizeof(COLORMAT)); |
| 680 |
mat[0][0] = mat[1][1] = mat[2][2] = 1.f; |
| 681 |
return(1); |
| 682 |
} |
| 683 |
if (CEQ(pr[WHT][CIEX],0.) | CEQ(pr[WHT][CIEY],0.)) |
| 684 |
return(0); |
| 685 |
C_rD = (1./pr[WHT][CIEY]) * |
| 686 |
( pr[WHT][CIEX]*(pr[GRN][CIEY] - pr[BLU][CIEY]) - |
| 687 |
pr[WHT][CIEY]*(pr[GRN][CIEX] - pr[BLU][CIEX]) + |
| 688 |
pr[GRN][CIEX]*pr[BLU][CIEY] - pr[BLU][CIEX]*pr[GRN][CIEY] ) ; |
| 689 |
C_gD = (1./pr[WHT][CIEY]) * |
| 690 |
( pr[WHT][CIEX]*(pr[BLU][CIEY] - pr[RED][CIEY]) - |
| 691 |
pr[WHT][CIEY]*(pr[BLU][CIEX] - pr[RED][CIEX]) - |
| 692 |
pr[RED][CIEX]*pr[BLU][CIEY] + pr[BLU][CIEX]*pr[RED][CIEY] ) ; |
| 693 |
C_bD = (1./pr[WHT][CIEY]) * |
| 694 |
( pr[WHT][CIEX]*(pr[RED][CIEY] - pr[GRN][CIEY]) - |
| 695 |
pr[WHT][CIEY]*(pr[RED][CIEX] - pr[GRN][CIEX]) + |
| 696 |
pr[RED][CIEX]*pr[GRN][CIEY] - pr[GRN][CIEX]*pr[RED][CIEY] ) ; |
| 697 |
D = pr[RED][CIEX]*(pr[GRN][CIEY] - pr[BLU][CIEY]) + |
| 698 |
pr[GRN][CIEX]*(pr[BLU][CIEY] - pr[RED][CIEY]) + |
| 699 |
pr[BLU][CIEX]*(pr[RED][CIEY] - pr[GRN][CIEY]) ; |
| 700 |
if (CEQ(D,0.)) |
| 701 |
return(0); |
| 702 |
mat[0][0] = pr[RED][CIEX]*C_rD/D; |
| 703 |
mat[0][1] = pr[GRN][CIEX]*C_gD/D; |
| 704 |
mat[0][2] = pr[BLU][CIEX]*C_bD/D; |
| 705 |
mat[1][0] = pr[RED][CIEY]*C_rD/D; |
| 706 |
mat[1][1] = pr[GRN][CIEY]*C_gD/D; |
| 707 |
mat[1][2] = pr[BLU][CIEY]*C_bD/D; |
| 708 |
mat[2][0] = (1.-pr[RED][CIEX]-pr[RED][CIEY])*C_rD/D; |
| 709 |
mat[2][1] = (1.-pr[GRN][CIEX]-pr[GRN][CIEY])*C_gD/D; |
| 710 |
mat[2][2] = (1.-pr[BLU][CIEX]-pr[BLU][CIEY])*C_bD/D; |
| 711 |
return(1); |
| 712 |
} |
| 713 |
|
| 714 |
|
| 715 |
int |
| 716 |
comprgb2rgbmat( /* compute conversion from RGB1 to RGB2 */ |
| 717 |
COLORMAT mat, |
| 718 |
RGBPRIMS pr1, |
| 719 |
RGBPRIMS pr2 |
| 720 |
) |
| 721 |
{ |
| 722 |
COLORMAT pr1toxyz, xyztopr2; |
| 723 |
|
| 724 |
if (pr1 == pr2) { |
| 725 |
memset(mat, 0, sizeof(COLORMAT)); |
| 726 |
mat[0][0] = mat[1][1] = mat[2][2] = 1.f; |
| 727 |
return(1); |
| 728 |
} |
| 729 |
if (!comprgb2xyzmat(pr1toxyz, pr1)) |
| 730 |
return(0); |
| 731 |
if (!compxyz2rgbmat(xyztopr2, pr2)) |
| 732 |
return(0); |
| 733 |
/* combine transforms */ |
| 734 |
multcolormat(mat, pr1toxyz, xyztopr2); |
| 735 |
return(1); |
| 736 |
} |
| 737 |
|
| 738 |
|
| 739 |
int |
| 740 |
compxyzWBmat( /* CIE von Kries transform from wht1 to wht2 */ |
| 741 |
COLORMAT mat, |
| 742 |
const float wht1[2], |
| 743 |
const float wht2[2] |
| 744 |
) |
| 745 |
{ |
| 746 |
COLOR cw1, cw2; |
| 747 |
if (XYEQ(wht1,wht2)) { |
| 748 |
memset(mat, 0, sizeof(COLORMAT)); |
| 749 |
mat[0][0] = mat[1][1] = mat[2][2] = 1.f; |
| 750 |
return(1); |
| 751 |
} |
| 752 |
if (CEQ(wht1[CIEX],0.) | CEQ(wht1[CIEY],0.)) |
| 753 |
return(0); |
| 754 |
cw1[RED] = wht1[CIEX]/wht1[CIEY]; |
| 755 |
cw1[GRN] = 1.; |
| 756 |
cw1[BLU] = (1. - wht1[CIEX] - wht1[CIEY])/wht1[CIEY]; |
| 757 |
colortrans(cw1, vkmat, cw1); |
| 758 |
if (CEQ(wht2[CIEX],0.) | CEQ(wht2[CIEY],0.)) |
| 759 |
return(0); |
| 760 |
cw2[RED] = wht2[CIEX]/wht2[CIEY]; |
| 761 |
cw2[GRN] = 1.; |
| 762 |
cw2[BLU] = (1. - wht2[CIEX] - wht2[CIEY])/wht2[CIEY]; |
| 763 |
colortrans(cw2, vkmat, cw2); |
| 764 |
if (CEQ(cw1[RED],0.) | CEQ(cw1[GRN],0.) | CEQ(cw1[BLU],0.)) |
| 765 |
return(0); |
| 766 |
mat[0][0] = cw2[RED]/cw1[RED]; |
| 767 |
mat[1][1] = cw2[GRN]/cw1[GRN]; |
| 768 |
mat[2][2] = cw2[BLU]/cw1[BLU]; |
| 769 |
mat[0][1] = mat[0][2] = mat[1][0] = |
| 770 |
mat[1][2] = mat[2][0] = mat[2][1] = 0.0; |
| 771 |
multcolormat(mat, vkmat, mat); |
| 772 |
multcolormat(mat, mat, ivkmat); |
| 773 |
return(1); |
| 774 |
} |
| 775 |
|
| 776 |
|
| 777 |
int |
| 778 |
compxyz2rgbWBmat( /* von Kries conversion from CIE to RGB space */ |
| 779 |
COLORMAT mat, |
| 780 |
RGBPRIMS pr |
| 781 |
) |
| 782 |
{ |
| 783 |
COLORMAT wbmat; |
| 784 |
|
| 785 |
if (!compxyz2rgbmat(mat, pr)) |
| 786 |
return(0); |
| 787 |
if (XYEQ(pr[WHT],xyneu)) |
| 788 |
return(1); |
| 789 |
if (!compxyzWBmat(wbmat, xyneu, pr[WHT])) |
| 790 |
return(0); |
| 791 |
multcolormat(mat, wbmat, mat); |
| 792 |
return(1); |
| 793 |
} |
| 794 |
|
| 795 |
int |
| 796 |
comprgb2xyzWBmat( /* von Kries conversion from RGB to CIE space */ |
| 797 |
COLORMAT mat, |
| 798 |
RGBPRIMS pr |
| 799 |
) |
| 800 |
{ |
| 801 |
COLORMAT wbmat; |
| 802 |
|
| 803 |
if (!comprgb2xyzmat(mat, pr)) |
| 804 |
return(0); |
| 805 |
if (XYEQ(pr[WHT],xyneu)) |
| 806 |
return(1); |
| 807 |
if (!compxyzWBmat(wbmat, pr[WHT], xyneu)) |
| 808 |
return(0); |
| 809 |
multcolormat(mat, mat, wbmat); |
| 810 |
return(1); |
| 811 |
} |
| 812 |
|
| 813 |
int |
| 814 |
comprgb2rgbWBmat( /* von Kries conversion from RGB1 to RGB2 */ |
| 815 |
COLORMAT mat, |
| 816 |
RGBPRIMS pr1, |
| 817 |
RGBPRIMS pr2 |
| 818 |
) |
| 819 |
{ |
| 820 |
COLORMAT pr1toxyz, xyztopr2, wbmat; |
| 821 |
|
| 822 |
if (pr1 == pr2) { |
| 823 |
memset(mat, 0, sizeof(COLORMAT)); |
| 824 |
mat[0][0] = mat[1][1] = mat[2][2] = 1.f; |
| 825 |
return(1); |
| 826 |
} |
| 827 |
if (!comprgb2xyzmat(pr1toxyz, pr1)) |
| 828 |
return(0); |
| 829 |
if (!compxyzWBmat(wbmat, pr1[WHT], pr2[WHT])) |
| 830 |
return(0); |
| 831 |
if (!compxyz2rgbmat(xyztopr2, pr2)) |
| 832 |
return(0); |
| 833 |
/* combine transforms */ |
| 834 |
multcolormat(mat, pr1toxyz, wbmat); |
| 835 |
multcolormat(mat, mat, xyztopr2); |
| 836 |
return(1); |
| 837 |
} |
