1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
/* $Xorg: LuvGcLC.c,v 1.3 2000/08/17 19:44:41 cpqbld Exp $ */
/*
* Code and supporting documentation (c) Copyright 1990 1991 Tektronix, Inc.
* All Rights Reserved
*
* This file is a component of an X Window System-specific implementation
* of XCMS based on the TekColor Color Management System. Permission is
* hereby granted to use, copy, modify, sell, and otherwise distribute this
* software and its documentation for any purpose and without fee, provided
* that this copyright, permission, and disclaimer notice is reproduced in
* all copies of this software and in supporting documentation. TekColor
* is a trademark of Tektronix, Inc.
*
* Tektronix makes no representation about the suitability of this software
* for any purpose. It is provided "as is" and with all faults.
*
* TEKTRONIX DISCLAIMS ALL WARRANTIES APPLICABLE TO THIS SOFTWARE,
* INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE. IN NO EVENT SHALL TEKTRONIX BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
* RESULTING FROM LOSS OF USE, DATA, OR PROFITS, WHETHER IN AN ACTION OF
* CONTRACT, NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR THE PERFORMANCE OF THIS SOFTWARE.
*
* NAME
* CIELuvGcLC.c
*
* DESCRIPTION
* Source for XcmsCIELuvClipLuv() gamut
* compression function.
*/
/* $XFree86$ */
#include "Xlibint.h"
#include "Xcmsint.h"
#include <math.h>
#include "Cv.h"
/*
* INTERNALS
* Internal defines that need NOT be exported to any package or
* program using this package.
*/
#define MAXBISECTCOUNT 100
/************************************************************************
* *
* PUBLIC ROUTINES *
* *
************************************************************************/
/*
* NAME
* XcmsCIELuvClipLuv - Return the closest L* and chroma
*
* SYNOPSIS
*/
/* ARGSUSED */
Status
XcmsCIELuvClipLuv (ccc, pColors_in_out, nColors, i, pCompressed)
XcmsCCC ccc;
XcmsColor *pColors_in_out;
unsigned int nColors;
unsigned int i;
Bool *pCompressed;
/*
* DESCRIPTION
* This routine will find the closest L* and chroma
* for a specific hue. The color input is converted to
* CIE L*u*v* format and returned as CIE XYZ format.
*
* Since this routine works with the L* within
* pColor_in_out intermediate results may be returned
* even though it may be invalid.
*
* RETURNS
* XcmsFailure - Failure
* XcmsSuccess - Succeeded
*
*/
{
Status retval;
XcmsCCCRec myCCC;
XcmsColor *pColor;
XcmsColor Luv_max;
XcmsFloat hue, chroma, maxChroma;
XcmsFloat Chroma, bestChroma, Lstar, maxLstar, saveLstar;
XcmsFloat bestLstar, bestustar, bestvstar;
XcmsFloat nT, saveDist, tmpDist;
XcmsRGBi rgb_max;
int nCount, nMaxCount, nI, nILast;
/* Use my own CCC */
memcpy ((char *)&myCCC, (char *)ccc, sizeof(XcmsCCCRec));
myCCC.clientWhitePt.format = XcmsUndefinedFormat;/* inherit screen white */
myCCC.gamutCompProc = (XcmsCompressionProc)NULL;/* no gamut compression func */
/*
* Color specification passed as input can be assumed to:
* 1. Be in XcmsCIEXYZFormat
* 2. Already be white point adjusted for the Screen White Point.
* This means that the white point now associated with this
* color spec is the Screen White Point (even if the
* ccc->clientWhitePt differs).
*/
pColor = pColors_in_out + i;
if (ccc->visual->class < StaticColor) {
/*
* GRAY !
*/
_XcmsDIConvertColors(ccc, pColor, ScreenWhitePointOfCCC(ccc),
1, XcmsCIELuvFormat);
_XcmsDIConvertColors(ccc, pColor, ScreenWhitePointOfCCC(ccc),
1, XcmsCIEXYZFormat);
if (pCompressed) {
*(pCompressed + i) = True;
}
return(XcmsSuccess);
}
/* Convert from CIEXYZ to CIELuv format */
if (_XcmsDIConvertColors(&myCCC, pColor,
ScreenWhitePointOfCCC(&myCCC), 1, XcmsCIELuvFormat)
== XcmsFailure) {
return(XcmsFailure);
}
/* Step 1: compute the maximum L* and chroma for this hue. */
/* This copy may be overkill but it preserves the pixel etc. */
saveLstar = pColor->spec.CIELuv.L_star;
hue = XCMS_CIELUV_PMETRIC_HUE(pColor->spec.CIELuv.u_star,
pColor->spec.CIELuv.v_star);
chroma = XCMS_CIELUV_PMETRIC_CHROMA(pColor->spec.CIELuv.u_star,
pColor->spec.CIELuv.v_star);
memcpy((char *)&Luv_max, (char *)pColor, sizeof(XcmsColor));
if (_XcmsCIELuvQueryMaxLCRGB (&myCCC, hue, &Luv_max, &rgb_max)
== XcmsFailure) {
return (XcmsFailure);
}
maxLstar = Luv_max.spec.CIELuv.L_star;
/* Now check and return the appropriate L* */
if (saveLstar == maxLstar) {
/* When the L* input is equal to the maximum L* */
/* merely return the maximum Luv point. */
memcpy((char *)pColor, (char *)&Luv_max, sizeof(XcmsColor));
retval = _XcmsDIConvertColors(&myCCC, pColor,
ScreenWhitePointOfCCC(&myCCC), 1, XcmsCIEXYZFormat);
} else {
/* return the closest point on the hue leaf. */
/* must do a bisection here to compute the delta e. */
maxChroma = XCMS_CIELUV_PMETRIC_CHROMA(Luv_max.spec.CIELuv.u_star,
Luv_max.spec.CIELuv.v_star);
nMaxCount = MAXBISECTCOUNT;
nI = nMaxCount / 2;
bestLstar = Lstar = pColor->spec.CIELuv.L_star;
bestustar = pColor->spec.CIELuv.u_star;
bestvstar = pColor->spec.CIELuv.v_star;
bestChroma = Chroma = chroma;
saveDist = XCMS_SQRT(((Chroma - maxChroma) * (Chroma - maxChroma)) +
((Lstar - maxLstar) * (Lstar - maxLstar)));
for (nCount = 0; nCount < nMaxCount; nCount++) {
nT = (XcmsFloat) nI / (XcmsFloat) nMaxCount;
if (saveLstar > maxLstar) {
pColor->spec.RGBi.red = rgb_max.red * (1.0 - nT) + nT;
pColor->spec.RGBi.green = rgb_max.green * (1.0 - nT) + nT;
pColor->spec.RGBi.blue = rgb_max.blue * (1.0 - nT) + nT;
} else {
pColor->spec.RGBi.red = rgb_max.red - (rgb_max.red * nT);
pColor->spec.RGBi.green = rgb_max.green - (rgb_max.green * nT);
pColor->spec.RGBi.blue = rgb_max.blue - (rgb_max.blue * nT);
}
pColor->format = XcmsRGBiFormat;
/* Convert from RGBi to CIE Luv */
if (_XcmsConvertColorsWithWhitePt(&myCCC, pColor,
ScreenWhitePointOfCCC(&myCCC), 1, XcmsCIELuvFormat,
(Bool *) NULL) == XcmsFailure) {
return (XcmsFailure);
}
chroma = XCMS_CIELUV_PMETRIC_CHROMA(pColor->spec.CIELuv.u_star,
pColor->spec.CIELuv.v_star);
tmpDist = XCMS_SQRT(((Chroma - chroma) * (Chroma - chroma)) +
((Lstar - pColor->spec.CIELuv.L_star) *
(Lstar - pColor->spec.CIELuv.L_star)));
nILast = nI;
if (tmpDist > saveDist) {
nI /= 2;
} else {
nI = (nMaxCount + nI) / 2;
saveDist = tmpDist;
bestLstar = pColor->spec.CIELuv.L_star;
bestustar = pColor->spec.CIELuv.u_star;
bestvstar = pColor->spec.CIELuv.v_star;
bestChroma = chroma;
}
if (nI == nILast || nI == 0) {
break;
}
}
if (bestChroma >= maxChroma) {
pColor->spec.CIELuv.L_star = maxLstar;
pColor->spec.CIELuv.u_star = Luv_max.spec.CIELuv.u_star;
pColor->spec.CIELuv.v_star = Luv_max.spec.CIELuv.v_star;
} else {
pColor->spec.CIELuv.L_star = bestLstar;
pColor->spec.CIELuv.u_star = bestustar;
pColor->spec.CIELuv.v_star = bestvstar;
}
retval = _XcmsDIConvertColors(&myCCC, pColor,
ScreenWhitePointOfCCC(&myCCC), 1, XcmsCIEXYZFormat);
if (retval != XcmsFailure && pCompressed != NULL) {
*(pCompressed + i) = True;
}
}
return(retval);
}
|
