[wxWidgets.git] / src / tiff / tif_color.c

/* $Header$ */

/*
 * Copyright (c) 1988-1997 Sam Leffler
 * Copyright (c) 1991-1997 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and 
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Sam Leffler and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Sam Leffler and Silicon Graphics.
 * 
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
 * 
 * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 
 * OF THIS SOFTWARE.
 */

/*
 * CIE L*a*b* to CIE XYZ and CIE XYZ to RGB conversion routines are taken
 * from the VIPS library (http://www.vips.ecs.soton.ac.uk) with
 * the permission of John Cupitt, the VIPS author.
 */

/*
 * TIFF Library.
 *
 * Color space conversion routines.
 */

#include "tiffiop.h"
#include <math.h>

/*
 * Convert color value from the CIE L*a*b* 1976 space to CIE XYZ.
 */
void
TIFFCIELabToXYZ(TIFFCIELabToRGB *cielab, uint32 l, int32 a, int32 b,
		float *X, float *Y, float *Z)
{
	float L = (float)l * 100.0F / 255.0F;
	float cby, tmp;

	if( L < 8.856F ) {
		*Y = (L * cielab->Y0) / 903.292F;
		cby = 7.787F * (*Y / cielab->Y0) + 16.0F / 116.0F;
	} else {
		cby = (L + 16.0F) / 116.0F;
		*Y = cielab->Y0 * cby * cby * cby;
	}

	tmp = (float)a / 500.0F + cby;
	if( tmp < 0.2069F )
		*X = cielab->X0 * (tmp - 0.13793F) / 7.787F;
	else    
		*X = cielab->X0 * tmp * tmp * tmp;

	tmp = cby - (float)b / 200.0F;
	if( tmp < 0.2069F )
		*Z = cielab->Z0 * (tmp - 0.13793F) / 7.787F;
	else    
		*Z = cielab->Z0 * tmp * tmp * tmp;
}

#define RINT(R) ((uint32)((R)>0?((R)+0.5):((R)-0.5)))
/*
 * Convert color value from the XYZ space to RGB.
 */
void
TIFFXYZToRGB(TIFFCIELabToRGB *cielab, float X, float Y, float Z,
	     uint32 *r, uint32 *g, uint32 *b)
{
	int i;
	float Yr, Yg, Yb;
	float *matrix = &cielab->display.d_mat[0][0];

	/* Multiply through the matrix to get luminosity values. */
	Yr =  matrix[0] * X + matrix[1] * Y + matrix[2] * Z;
	Yg =  matrix[3] * X + matrix[4] * Y + matrix[5] * Z;
	Yb =  matrix[6] * X + matrix[7] * Y + matrix[8] * Z;

	/* Clip input */
	Yr = TIFFmax( Yr, cielab->display.d_Y0R );
	Yg = TIFFmax( Yg, cielab->display.d_Y0G );
	Yb = TIFFmax( Yb, cielab->display.d_Y0B );

	/* Turn luminosity to colour value. */
	i = TIFFmin(cielab->range,
		    (int)((Yr - cielab->display.d_Y0R) / cielab->rstep));
	*r = RINT(cielab->Yr2r[i]);

	i = TIFFmin(cielab->range,
		    (int)((Yg - cielab->display.d_Y0G) / cielab->gstep));
	*g = RINT(cielab->Yg2g[i]);

	i = TIFFmin(cielab->range,
		    (int)((Yb - cielab->display.d_Y0B) / cielab->bstep));
	*b = RINT(cielab->Yb2b[i]);

	/* Clip output. */
	*r = TIFFmin( *r, cielab->display.d_Vrwr );
	*g = TIFFmin( *g, cielab->display.d_Vrwg );
	*b = TIFFmin( *b, cielab->display.d_Vrwb );
}
#undef RINT

/* 
 * Allocate conversion state structures and make look_up tables for
 * the Yr,Yb,Yg <=> r,g,b conversions.
 */
int
TIFFCIELabToRGBInit(TIFFCIELabToRGB* cielab,
		    TIFFDisplay *display, float *refWhite)
{
	int i;
	float gamma;

	cielab->range = CIELABTORGB_TABLE_RANGE;

	_TIFFmemcpy(&cielab->display, display, sizeof(TIFFDisplay));

	/* Red */
	gamma = 1.0F / cielab->display.d_gammaR ;
	cielab->rstep =
		(cielab->display.d_YCR - cielab->display.d_Y0R)	/ cielab->range;
	for(i = 0; i <= cielab->range; i++) {
		cielab->Yr2r[i] = cielab->display.d_Vrwr
		    * ((float)pow((double)i / cielab->range, gamma));
	}

	/* Green */
	gamma = 1.0F / cielab->display.d_gammaG ;
	cielab->gstep =
	    (cielab->display.d_YCR - cielab->display.d_Y0R) / cielab->range;
	for(i = 0; i <= cielab->range; i++) {
		cielab->Yg2g[i] = cielab->display.d_Vrwg
		    * ((float)pow((double)i / cielab->range, gamma));
	}

	/* Blue */
	gamma = 1.0F / cielab->display.d_gammaB ;
	cielab->bstep =
	    (cielab->display.d_YCR - cielab->display.d_Y0R) / cielab->range;
	for(i = 0; i <= cielab->range; i++) {
		cielab->Yb2b[i] = cielab->display.d_Vrwb
		    * ((float)pow((double)i / cielab->range, gamma));
	}

	/* Init reference white point */
	cielab->X0 = refWhite[0];
	cielab->Y0 = refWhite[1];
	cielab->Z0 = refWhite[2];

	return 0;
}

/* 
 * Convert color value from the YCbCr space to CIE XYZ.
 * The colorspace conversion algorithm comes from the IJG v5a code;
 * see below for more information on how it works.
 */
#define	SHIFT			16
#define	FIX(x)			((int32)((x) * (1L<<SHIFT) + 0.5))
#define	ONE_HALF		((int32)(1<<(SHIFT-1)))
#define	Code2V(c, RB, RW, CR)	((((c)-(int32)(RB))*(float)(CR))/(float)((RW)-(RB)))
#define	CLAMP(f,min,max)	((f)<(min)?(min):(f)>(max)?(max):(f))

void
TIFFYCbCrtoRGB(TIFFYCbCrToRGB *ycbcr, uint32 Y, int32 Cb, int32 Cr,
	       uint32 *r, uint32 *g, uint32 *b)
{
	/* XXX: Only 8-bit YCbCr input supported for now */
	Y = CLAMP(Y, 0, 255), Cb = CLAMP(Cb, 0, 255), Cr = CLAMP(Cr, 0, 255);

	*r = ycbcr->clamptab[ycbcr->Y_tab[Y] + ycbcr->Cr_r_tab[Cr]];
	*g = ycbcr->clamptab[ycbcr->Y_tab[Y]
	    + (int)((ycbcr->Cb_g_tab[Cb] + ycbcr->Cr_g_tab[Cr]) >> SHIFT)];
	*b = ycbcr->clamptab[ycbcr->Y_tab[Y] + ycbcr->Cb_b_tab[Cb]];
}

/*
 * Initialize the YCbCr->RGB conversion tables.  The conversion
 * is done according to the 6.0 spec:
 *
 *    R = Y + Cr*(2 - 2*LumaRed)
 *    B = Y + Cb*(2 - 2*LumaBlue)
 *    G =   Y
 *        - LumaBlue*Cb*(2-2*LumaBlue)/LumaGreen
 *        - LumaRed*Cr*(2-2*LumaRed)/LumaGreen
 *
 * To avoid floating point arithmetic the fractional constants that
 * come out of the equations are represented as fixed point values
 * in the range 0...2^16.  We also eliminate multiplications by
 * pre-calculating possible values indexed by Cb and Cr (this code
 * assumes conversion is being done for 8-bit samples).
 */
int
TIFFYCbCrToRGBInit(TIFFYCbCrToRGB* ycbcr, float *luma, float *refBlackWhite)
{
    TIFFRGBValue* clamptab;
    int i;
    
#define LumaRed	    luma[0]
#define LumaGreen   luma[1]
#define LumaBlue    luma[2]

    clamptab = (TIFFRGBValue*)(
	(tidata_t) ycbcr+TIFFroundup(sizeof (TIFFYCbCrToRGB), sizeof (long)));
    _TIFFmemset(clamptab, 0, 256);		/* v < 0 => 0 */
    ycbcr->clamptab = (clamptab += 256);
    for (i = 0; i < 256; i++)
	clamptab[i] = (TIFFRGBValue) i;
    _TIFFmemset(clamptab+256, 255, 2*256);	/* v > 255 => 255 */
    ycbcr->Cr_r_tab = (int*) (clamptab + 3*256);
    ycbcr->Cb_b_tab = ycbcr->Cr_r_tab + 256;
    ycbcr->Cr_g_tab = (int32*) (ycbcr->Cb_b_tab + 256);
    ycbcr->Cb_g_tab = ycbcr->Cr_g_tab + 256;
    ycbcr->Y_tab = ycbcr->Cb_g_tab + 256;

    { float f1 = 2-2*LumaRed;		int32 D1 = FIX(f1);
      float f2 = LumaRed*f1/LumaGreen;	int32 D2 = -FIX(f2);
      float f3 = 2-2*LumaBlue;		int32 D3 = FIX(f3);
      float f4 = LumaBlue*f3/LumaGreen;	int32 D4 = -FIX(f4);
      int x;

#undef LumaBlue
#undef LumaGreen
#undef LumaRed
      
      /*
       * i is the actual input pixel value in the range 0..255
       * Cb and Cr values are in the range -128..127 (actually
       * they are in a range defined by the ReferenceBlackWhite
       * tag) so there is some range shifting to do here when
       * constructing tables indexed by the raw pixel data.
       */
      for (i = 0, x = -128; i < 256; i++, x++) {
	    int32 Cr = (int32)Code2V(x, refBlackWhite[4] - 128.0F,
			    refBlackWhite[5] - 128.0F, 127);
	    int32 Cb = (int32)Code2V(x, refBlackWhite[2] - 128.0F,
			    refBlackWhite[3] - 128.0F, 127);

	    ycbcr->Cr_r_tab[i] = (int32)((D1*Cr + ONE_HALF)>>SHIFT);
	    ycbcr->Cb_b_tab[i] = (int32)((D3*Cb + ONE_HALF)>>SHIFT);
	    ycbcr->Cr_g_tab[i] = D2*Cr;
	    ycbcr->Cb_g_tab[i] = D4*Cb + ONE_HALF;
	    ycbcr->Y_tab[i] =
		    (int32)Code2V(x + 128, refBlackWhite[0], refBlackWhite[1], 255);
      }
    }

    return 0;
}
#undef	CLAMP
#undef	Code2V
#undef	SHIFT
#undef	ONE_HALF
#undef	FIX
Commit	Line	Data
7da02538 VZ	1	/* $Header$ */
	2
	3	/*
	4	* Copyright (c) 1988-1997 Sam Leffler
	5	* Copyright (c) 1991-1997 Silicon Graphics, Inc.
	6	*
	7	* Permission to use, copy, modify, distribute, and sell this software and
	8	* its documentation for any purpose is hereby granted without fee, provided
	9	* that (i) the above copyright notices and this permission notice appear in
	10	* all copies of the software and related documentation, and (ii) the names of
	11	* Sam Leffler and Silicon Graphics may not be used in any advertising or
	12	* publicity relating to the software without the specific, prior written
	13	* permission of Sam Leffler and Silicon Graphics.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
	16	* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
	17	* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
	18	*
	19	* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
	20	* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
	21	* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
	22	* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
	23	* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
	24	* OF THIS SOFTWARE.
	25	*/
	26
	27	/*
	28	* CIE Lab* to CIE XYZ and CIE XYZ to RGB conversion routines are taken
	29	* from the VIPS library (http://www.vips.ecs.soton.ac.uk) with
	30	* the permission of John Cupitt, the VIPS author.
	31	*/
	32
	33	/*
	34	* TIFF Library.
	35	*
	36	* Color space conversion routines.
	37	*/
	38
	39	#include "tiffiop.h"
	40	#include <math.h>
	41
	42	/*
	43	* Convert color value from the CIE Lab* 1976 space to CIE XYZ.
	44	*/
	45	void
	46	TIFFCIELabToXYZ(TIFFCIELabToRGB *cielab, uint32 l, int32 a, int32 b,
	47	float X, float Y, float *Z)
	48	{
	49	float L = (float)l * 100.0F / 255.0F;
	50	float cby, tmp;
	51
	52	if( L < 8.856F ) {
	53	Y = (L cielab->Y0) / 903.292F;
	54	cby = 7.787F * (*Y / cielab->Y0) + 16.0F / 116.0F;
	55	} else {
	56	cby = (L + 16.0F) / 116.0F;
	57	Y = cielab->Y0 cby * cby * cby;
	58	}
	59
	60	tmp = (float)a / 500.0F + cby;
	61	if( tmp < 0.2069F )
	62	X = cielab->X0 (tmp - 0.13793F) / 7.787F;
	63	else
	64	X = cielab->X0 tmp * tmp * tmp;
65
66	tmp = cby - (float)b / 200.0F;
67	if( tmp < 0.2069F )
68	Z = cielab->Z0 (tmp - 0.13793F) / 7.787F;
69	else
70	Z = cielab->Z0 tmp * tmp * tmp;
71	}
72
73	#define RINT(R) ((uint32)((R)>0?((R)+0.5):((R)-0.5)))
74	/*
75	* Convert color value from the XYZ space to RGB.
76	*/
77	void
78	TIFFXYZToRGB(TIFFCIELabToRGB *cielab, float X, float Y, float Z,
79	uint32 r, uint32 g, uint32 *b)
80	{
81	int i;
82	float Yr, Yg, Yb;
83	float *matrix = &cielab->display.d_mat[0][0];
84
85	/* Multiply through the matrix to get luminosity values. */
86	Yr = matrix[0] * X + matrix[1] * Y + matrix[2] * Z;
87	Yg = matrix[3] * X + matrix[4] * Y + matrix[5] * Z;
88	Yb = matrix[6] * X + matrix[7] * Y + matrix[8] * Z;
89
90	/* Clip input */
91	Yr = TIFFmax( Yr, cielab->display.d_Y0R );
92	Yg = TIFFmax( Yg, cielab->display.d_Y0G );
93	Yb = TIFFmax( Yb, cielab->display.d_Y0B );
94
95	/* Turn luminosity to colour value. */
96	i = TIFFmin(cielab->range,
97	(int)((Yr - cielab->display.d_Y0R) / cielab->rstep));
98	*r = RINT(cielab->Yr2r[i]);
99
100	i = TIFFmin(cielab->range,
101	(int)((Yg - cielab->display.d_Y0G) / cielab->gstep));
102	*g = RINT(cielab->Yg2g[i]);
103
104	i = TIFFmin(cielab->range,
105	(int)((Yb - cielab->display.d_Y0B) / cielab->bstep));
106	*b = RINT(cielab->Yb2b[i]);
107
108	/* Clip output. */
109	r = TIFFmin( r, cielab->display.d_Vrwr );
110	g = TIFFmin( g, cielab->display.d_Vrwg );
111	b = TIFFmin( b, cielab->display.d_Vrwb );
112	}
113	#undef RINT
114
115	/*
116	* Allocate conversion state structures and make look_up tables for
117	* the Yr,Yb,Yg <=> r,g,b conversions.
118	*/
119	int
120	TIFFCIELabToRGBInit(TIFFCIELabToRGB* cielab,
121	TIFFDisplay display, float refWhite)
122	{
123	int i;
124	float gamma;
125
126	cielab->range = CIELABTORGB_TABLE_RANGE;
127
128	_TIFFmemcpy(&cielab->display, display, sizeof(TIFFDisplay));
129
130	/* Red */
131	gamma = 1.0F / cielab->display.d_gammaR ;
132	cielab->rstep =
133	(cielab->display.d_YCR - cielab->display.d_Y0R) / cielab->range;
134	for(i = 0; i <= cielab->range; i++) {
135	cielab->Yr2r[i] = cielab->display.d_Vrwr
136	* ((float)pow((double)i / cielab->range, gamma));
137	}
138
139	/* Green */
140	gamma = 1.0F / cielab->display.d_gammaG ;
141	cielab->gstep =
142	(cielab->display.d_YCR - cielab->display.d_Y0R) / cielab->range;
143	for(i = 0; i <= cielab->range; i++) {
144	cielab->Yg2g[i] = cielab->display.d_Vrwg
145	* ((float)pow((double)i / cielab->range, gamma));
146	}
147
148	/* Blue */
149	gamma = 1.0F / cielab->display.d_gammaB ;
150	cielab->bstep =
151	(cielab->display.d_YCR - cielab->display.d_Y0R) / cielab->range;
152	for(i = 0; i <= cielab->range; i++) {
153	cielab->Yb2b[i] = cielab->display.d_Vrwb
154	* ((float)pow((double)i / cielab->range, gamma));
155	}
156
157	/* Init reference white point */
158	cielab->X0 = refWhite[0];
159	cielab->Y0 = refWhite[1];
160	cielab->Z0 = refWhite[2];
161
162	return 0;
163	}
164
165	/*
166	* Convert color value from the YCbCr space to CIE XYZ.
167	* The colorspace conversion algorithm comes from the IJG v5a code;
168	* see below for more information on how it works.
169	*/
170	#define SHIFT 16
171	#define FIX(x) ((int32)((x) * (1L<<SHIFT) + 0.5))
172	#define ONE_HALF ((int32)(1<<(SHIFT-1)))
173	#define Code2V(c, RB, RW, CR) ((((c)-(int32)(RB))*(float)(CR))/(float)((RW)-(RB)))
174	#define CLAMP(f,min,max) ((f)<(min)?(min):(f)>(max)?(max):(f))
175
176	void
177	TIFFYCbCrtoRGB(TIFFYCbCrToRGB *ycbcr, uint32 Y, int32 Cb, int32 Cr,
178	uint32 r, uint32 g, uint32 *b)
179	{
180	/* XXX: Only 8-bit YCbCr input supported for now */
181	Y = CLAMP(Y, 0, 255), Cb = CLAMP(Cb, 0, 255), Cr = CLAMP(Cr, 0, 255);
182
183	*r = ycbcr->clamptab[ycbcr->Y_tab[Y] + ycbcr->Cr_r_tab[Cr]];
184	*g = ycbcr->clamptab[ycbcr->Y_tab[Y]
185	+ (int)((ycbcr->Cb_g_tab[Cb] + ycbcr->Cr_g_tab[Cr]) >> SHIFT)];
186	*b = ycbcr->clamptab[ycbcr->Y_tab[Y] + ycbcr->Cb_b_tab[Cb]];
187	}
188
189	/*
190	* Initialize the YCbCr->RGB conversion tables. The conversion
191	* is done according to the 6.0 spec:
192	*
193	* R = Y + Cr(2 - 2LumaRed)
194	* B = Y + Cb(2 - 2LumaBlue)
195	* G = Y
196	* - LumaBlueCb(2-2*LumaBlue)/LumaGreen
197	* - LumaRedCr(2-2*LumaRed)/LumaGreen
198	*
199	* To avoid floating point arithmetic the fractional constants that
200	* come out of the equations are represented as fixed point values
201	* in the range 0...2^16. We also eliminate multiplications by
202	* pre-calculating possible values indexed by Cb and Cr (this code
203	* assumes conversion is being done for 8-bit samples).
204	*/
205	int
206	TIFFYCbCrToRGBInit(TIFFYCbCrToRGB* ycbcr, float luma, float refBlackWhite)
207	{
208	TIFFRGBValue* clamptab;
209	int i;
210
211	#define LumaRed luma[0]
212	#define LumaGreen luma[1]
213	#define LumaBlue luma[2]
214
215	clamptab = (TIFFRGBValue*)(
216	(tidata_t) ycbcr+TIFFroundup(sizeof (TIFFYCbCrToRGB), sizeof (long)));
217	_TIFFmemset(clamptab, 0, 256); /* v < 0 => 0 */
218	ycbcr->clamptab = (clamptab += 256);
219	for (i = 0; i < 256; i++)
220	clamptab[i] = (TIFFRGBValue) i;
221	_TIFFmemset(clamptab+256, 255, 2256); / v > 255 => 255 */
222	ycbcr->Cr_r_tab = (int) (clamptab + 3256);
223	ycbcr->Cb_b_tab = ycbcr->Cr_r_tab + 256;
224	ycbcr->Cr_g_tab = (int32*) (ycbcr->Cb_b_tab + 256);
225	ycbcr->Cb_g_tab = ycbcr->Cr_g_tab + 256;
226	ycbcr->Y_tab = ycbcr->Cb_g_tab + 256;
227
228	{ float f1 = 2-2*LumaRed; int32 D1 = FIX(f1);
229	float f2 = LumaRed*f1/LumaGreen; int32 D2 = -FIX(f2);
230	float f3 = 2-2*LumaBlue; int32 D3 = FIX(f3);
231	float f4 = LumaBlue*f3/LumaGreen; int32 D4 = -FIX(f4);
232	int x;
233
234	#undef LumaBlue
235	#undef LumaGreen
236	#undef LumaRed
237
238	/*
239	* i is the actual input pixel value in the range 0..255
240	* Cb and Cr values are in the range -128..127 (actually
241	* they are in a range defined by the ReferenceBlackWhite
242	* tag) so there is some range shifting to do here when
243	* constructing tables indexed by the raw pixel data.
244	*/
245	for (i = 0, x = -128; i < 256; i++, x++) {
246	int32 Cr = (int32)Code2V(x, refBlackWhite[4] - 128.0F,
247	refBlackWhite[5] - 128.0F, 127);
248	int32 Cb = (int32)Code2V(x, refBlackWhite[2] - 128.0F,
249	refBlackWhite[3] - 128.0F, 127);
250
251	ycbcr->Cr_r_tab[i] = (int32)((D1*Cr + ONE_HALF)>>SHIFT);
252	ycbcr->Cb_b_tab[i] = (int32)((D3*Cb + ONE_HALF)>>SHIFT);
253	ycbcr->Cr_g_tab[i] = D2*Cr;
254	ycbcr->Cb_g_tab[i] = D4*Cb + ONE_HALF;
255	ycbcr->Y_tab[i] =
256	(int32)Code2V(x + 128, refBlackWhite[0], refBlackWhite[1], 255);
257	}
258	}
259
260	return 0;
261	}
262	#undef CLAMP
263	#undef Code2V
264	#undef SHIFT
265	#undef ONE_HALF
266	#undef FIX
267
268