michael@0: /* vim: set ts=8 sw=8 noexpandtab: */
michael@0: //  qcms
michael@0: //  Copyright (C) 2009 Mozilla Foundation
michael@0: //  Copyright (C) 1998-2007 Marti Maria
michael@0: //
michael@0: // Permission is hereby granted, free of charge, to any person obtaining 
michael@0: // a copy of this software and associated documentation files (the "Software"), 
michael@0: // to deal in the Software without restriction, including without limitation 
michael@0: // the rights to use, copy, modify, merge, publish, distribute, sublicense, 
michael@0: // and/or sell copies of the Software, and to permit persons to whom the Software 
michael@0: // is furnished to do so, subject to the following conditions:
michael@0: //
michael@0: // The above copyright notice and this permission notice shall be included in 
michael@0: // all copies or substantial portions of the Software.
michael@0: //
michael@0: // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
michael@0: // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO 
michael@0: // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
michael@0: // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 
michael@0: // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
michael@0: // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
michael@0: // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
michael@0: 
michael@0: #ifndef _QCMS_TRANSFORM_UTIL_H
michael@0: #define _QCMS_TRANSFORM_UTIL_H
michael@0: 
michael@0: #include <stdlib.h>
michael@0: 
michael@0: #define CLU(table,x,y,z) table[(x*len + y*x_len + z*xy_len)*3]
michael@0: 
michael@0: //XXX: could use a bettername
michael@0: typedef uint16_t uint16_fract_t;
michael@0: 
michael@0: float lut_interp_linear(double value, uint16_t *table, int length);
michael@0: float lut_interp_linear_float(float value, float *table, int length);
michael@0: uint16_t lut_interp_linear16(uint16_t input_value, uint16_t *table, int length);
michael@0: 
michael@0: 
michael@0: static inline float lerp(float a, float b, float t)
michael@0: {
michael@0:         return a*(1.f-t) + b*t;
michael@0: }
michael@0: 
michael@0: static inline unsigned char clamp_u8(float v)
michael@0: {
michael@0:   if (v > 255.)
michael@0:     return 255;
michael@0:   else if (v < 0)
michael@0:     return 0;
michael@0:   else
michael@0:     return floorf(v+.5);
michael@0: }
michael@0: 
michael@0: static inline float clamp_float(float a)
michael@0: {
michael@0:   /* One would naturally write this function as the following:
michael@0:   if (a > 1.)
michael@0:     return 1.;
michael@0:   else if (a < 0)
michael@0:     return 0;
michael@0:   else
michael@0:     return a;
michael@0: 
michael@0:   However, that version will let NaNs pass through which is undesirable
michael@0:   for most consumers.
michael@0:   */
michael@0: 
michael@0:   if (a > 1.)
michael@0:     return 1.;
michael@0:   else if (a >= 0)
michael@0:     return a;
michael@0:   else // a < 0 or a is NaN
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: static inline float u8Fixed8Number_to_float(uint16_t x)
michael@0: {
michael@0:   // 0x0000 = 0.
michael@0:   // 0x0100 = 1.
michael@0:   // 0xffff = 255  + 255/256
michael@0:   return x/256.;
michael@0: }
michael@0: 
michael@0: float *build_input_gamma_table(struct curveType *TRC);
michael@0: struct matrix build_colorant_matrix(qcms_profile *p);
michael@0: void build_output_lut(struct curveType *trc,
michael@0:                       uint16_t **output_gamma_lut, size_t *output_gamma_lut_length);
michael@0: 
michael@0: struct matrix matrix_invert(struct matrix mat);
michael@0: qcms_bool compute_precache(struct curveType *trc, uint8_t *output);
michael@0: 
michael@0: 
michael@0: #endif