--- ray/src/common/spec_rgb.c 1998/10/07 17:11:40 2.10
+++ ray/src/common/spec_rgb.c 2003/02/22 02:07:22 2.11
@@ -1,23 +1,87 @@
-/* Copyright (c) 1997 Regents of the University of California */
-
#ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char RCSid[] = "$Id: spec_rgb.c,v 2.11 2003/02/22 02:07:22 greg Exp $";
#endif
-
/*
* Convert colors and spectral ranges.
+ * Added von Kries white-balance calculations 10/01 (GW).
+ *
+ * Externals declared in color.h
*/
+/* ====================================================================
+ * The Radiance Software License, Version 1.0
+ *
+ * Copyright (c) 1990 - 2002 The Regents of the University of California,
+ * through Lawrence Berkeley National Laboratory. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ * if any, must include the following acknowledgment:
+ * "This product includes Radiance software
+ * (http://radsite.lbl.gov/)
+ * developed by the Lawrence Berkeley National Laboratory
+ * (http://www.lbl.gov/)."
+ * Alternately, this acknowledgment may appear in the software itself,
+ * if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
+ * and "The Regents of the University of California" must
+ * not be used to endorse or promote products derived from this
+ * software without prior written permission. For written
+ * permission, please contact radiance@radsite.lbl.gov.
+ *
+ * 5. Products derived from this software may not be called "Radiance",
+ * nor may "Radiance" appear in their name, without prior written
+ * permission of Lawrence Berkeley National Laboratory.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of Lawrence Berkeley National Laboratory. For more
+ * information on Lawrence Berkeley National Laboratory, please see
+ * .
+ */
+
#include "color.h"
+#include
-#define CEPS 1e-7 /* color epsilon */
+#define CEPS 1e-4 /* color epsilon */
+#define CEQ(v1,v2) ((v1) <= (v2)+CEPS && (v2) <= (v1)+CEPS)
-RGBPRIMS stdprims = STDPRIMS; /* standard primary chromaticities */
+#define XYEQ(c1,c2) (CEQ((c1)[CIEX],(c2)[CIEX]) && CEQ((c1)[CIEY],(c2)[CIEY]))
+
+RGBPRIMS stdprims = STDPRIMS; /* standard primary chromaticities */
+
COLOR cblack = BLKCOLOR; /* global black color */
COLOR cwhite = WHTCOLOR; /* global white color */
+float xyneu[2] = {1./3., 1./3.}; /* neutral xy chromaticities */
+
/*
* The following table contains the CIE tristimulus integrals
* for X, Y, and Z. The table is cumulative, so that
@@ -47,7 +111,7 @@ static BYTE chroma[3][NINC] = {
}
};
-COLORMAT xyz2rgbmat = { /* XYZ to RGB */
+COLORMAT xyz2rgbmat = { /* XYZ to RGB (no white balance) */
{(CIE_y_g - CIE_y_b - CIE_x_b*CIE_y_g + CIE_y_b*CIE_x_g)/CIE_C_rD,
(CIE_x_b - CIE_x_g - CIE_x_b*CIE_y_g + CIE_x_g*CIE_y_b)/CIE_C_rD,
(CIE_x_g*CIE_y_b - CIE_x_b*CIE_y_g)/CIE_C_rD},
@@ -59,7 +123,7 @@ COLORMAT xyz2rgbmat = { /* XYZ to RGB */
(CIE_x_r*CIE_y_g - CIE_x_g*CIE_y_r)/CIE_C_bD}
};
-COLORMAT rgb2xyzmat = { /* RGB to XYZ */
+COLORMAT rgb2xyzmat = { /* RGB to XYZ (no white balance) */
{CIE_x_r*CIE_C_rD/CIE_D,CIE_x_g*CIE_C_gD/CIE_D,CIE_x_b*CIE_C_bD/CIE_D},
{CIE_y_r*CIE_C_rD/CIE_D,CIE_y_g*CIE_C_gD/CIE_D,CIE_y_b*CIE_C_bD/CIE_D},
{(1.-CIE_x_r-CIE_y_r)*CIE_C_rD/CIE_D,
@@ -67,8 +131,20 @@ COLORMAT rgb2xyzmat = { /* RGB to XYZ */
(1.-CIE_x_b-CIE_y_b)*CIE_C_bD/CIE_D}
};
+COLORMAT vkmat = { /* Sharp primary matrix */
+ { 1.2694, -0.0988, -0.1706},
+ {-0.8364, 1.8006, 0.0357},
+ { 0.0297, -0.0315, 1.0018}
+};
+COLORMAT ivkmat = { /* inverse Sharp primary matrix */
+ { 0.8156, 0.0472, 0.1372},
+ { 0.3791, 0.5769, 0.0440},
+ {-0.0123, 0.0167, 0.9955}
+};
+
+void
spec_rgb(col, s, e) /* compute RGB color from spectral range */
COLOR col;
int s, e;
@@ -80,6 +156,7 @@ int s, e;
}
+void
spec_cie(col, s, e) /* compute a color from a spectral range */
COLOR col; /* returned color */
int s, e; /* starting and ending wavelengths */
@@ -114,8 +191,10 @@ int s, e; /* starting and ending wavelengths */
}
+void
cie_rgb(rgb, xyz) /* convert CIE color to standard RGB */
-COLOR rgb, xyz;
+COLOR rgb;
+COLOR xyz;
{
colortrans(rgb, xyz2rgbmat, xyz);
clipgamut(rgb, xyz[CIEY], CGAMUT_LOWER, cblack, cwhite);
@@ -168,9 +247,11 @@ COLOR lower, upper;
}
+void
colortrans(c2, mat, c1) /* convert c1 by mat and put into c2 */
+register COLOR c2;
register COLORMAT mat;
-register COLOR c1, c2;
+register COLOR c1;
{
COLOR cout;
@@ -182,8 +263,10 @@ register COLOR c1, c2;
}
+void
multcolormat(m3, m2, m1) /* multiply m1 by m2 and put into m3 */
-COLORMAT m1, m2, m3; /* m3 can be either m1 or m2 w/o harm */
+COLORMAT m3; /* m3 can be either m1 or m2 w/o harm */
+COLORMAT m2, m1;
{
COLORMAT mt;
register int i, j;
@@ -197,6 +280,7 @@ COLORMAT m1, m2, m3; /* m3 can be either m1 or m2 w/
}
+void
compxyz2rgbmat(mat, pr) /* compute conversion from CIE to RGB space */
COLORMAT mat;
register RGBPRIMS pr;
@@ -247,6 +331,7 @@ register RGBPRIMS pr;
}
+void
comprgb2xyzmat(mat, pr) /* compute conversion from RGB to CIE space */
COLORMAT mat;
register RGBPRIMS pr;
@@ -284,6 +369,7 @@ register RGBPRIMS pr;
}
+void
comprgb2rgbmat(mat, pr1, pr2) /* compute conversion from RGB1 to RGB2 */
COLORMAT mat;
RGBPRIMS pr1, pr2;
@@ -300,4 +386,84 @@ RGBPRIMS pr1, pr2;
compxyz2rgbmat(xyztopr2, pr2);
/* combine transforms */
multcolormat(mat, pr1toxyz, xyztopr2);
+}
+
+
+void
+compxyzWBmat(mat, wht1, wht2) /* CIE von Kries transform from wht1 to wht2 */
+COLORMAT mat;
+float wht1[2], wht2[2];
+{
+ COLOR cw1, cw2;
+ if (XYEQ(wht1,wht2)) {
+ mat[0][0] = mat[1][1] = mat[2][2] = 1.0;
+ mat[0][1] = mat[0][2] = mat[1][0] =
+ mat[1][2] = mat[2][0] = mat[2][1] = 0.0;
+ return;
+ }
+ cw1[RED] = wht1[CIEX]/wht1[CIEY];
+ cw1[GRN] = 1.;
+ cw1[BLU] = (1. - wht1[CIEX] - wht1[CIEY])/wht1[CIEY];
+ colortrans(cw1, vkmat, cw1);
+ cw2[RED] = wht2[CIEX]/wht2[CIEY];
+ cw2[GRN] = 1.;
+ cw2[BLU] = (1. - wht2[CIEX] - wht2[CIEY])/wht2[CIEY];
+ colortrans(cw2, vkmat, cw2);
+ mat[0][0] = cw2[RED]/cw1[RED];
+ mat[1][1] = cw2[GRN]/cw1[GRN];
+ mat[2][2] = cw2[BLU]/cw1[BLU];
+ mat[0][1] = mat[0][2] = mat[1][0] =
+ mat[1][2] = mat[2][0] = mat[2][1] = 0.0;
+ multcolormat(mat, vkmat, mat);
+ multcolormat(mat, mat, ivkmat);
+}
+
+
+void
+compxyz2rgbWBmat(mat, pr) /* von Kries conversion from CIE to RGB space */
+COLORMAT mat;
+RGBPRIMS pr;
+{
+ COLORMAT wbmat;
+
+ compxyz2rgbmat(mat, pr);
+ if (XYEQ(pr[WHT],xyneu))
+ return;
+ compxyzWBmat(wbmat, xyneu, pr[WHT]);
+ multcolormat(mat, wbmat, mat);
+}
+
+void
+comprgb2xyzWBmat(mat, pr) /* von Kries conversion from RGB to CIE space */
+COLORMAT mat;
+RGBPRIMS pr;
+{
+ COLORMAT wbmat;
+
+ comprgb2xyzmat(mat, pr);
+ if (XYEQ(pr[WHT],xyneu))
+ return;
+ compxyzWBmat(wbmat, pr[WHT], xyneu);
+ multcolormat(mat, mat, wbmat);
+}
+
+void
+comprgb2rgbWBmat(mat, pr1, pr2) /* von Kries conversion from RGB1 to RGB2 */
+COLORMAT mat;
+RGBPRIMS pr1, pr2;
+{
+ COLORMAT pr1toxyz, xyztopr2, wbmat;
+
+ if (pr1 == pr2) {
+ mat[0][0] = mat[1][1] = mat[2][2] = 1.0;
+ mat[0][1] = mat[0][2] = mat[1][0] =
+ mat[1][2] = mat[2][0] = mat[2][1] = 0.0;
+ return;
+ }
+ comprgb2xyzmat(pr1toxyz, pr1);
+ compxyzWBmat(wbmat, pr1[WHT], pr2[WHT]);
+ compxyz2rgbmat(xyztopr2, pr2);
+ /* combine transforms */
+ multcolormat(mat, pr1toxyz, wbmat);
+ multcolormat(mat, mat, xyztopr2);
}