gfx/qcms/transform_util.h

   1 /* vim: set ts=8 sw=8 noexpandtab: */
   2 //  qcms
   3 //  Copyright (C) 2009 Mozilla Foundation
   4 //  Copyright (C) 1998-2007 Marti Maria
   5 //
   6 // Permission is hereby granted, free of charge, to any person obtaining
   7 // a copy of this software and associated documentation files (the "Software"),
   8 // to deal in the Software without restriction, including without limitation
   9 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10 // and/or sell copies of the Software, and to permit persons to whom the Software
  11 // is furnished to do so, subject to the following conditions:
  12 //
  13 // The above copyright notice and this permission notice shall be included in
  14 // all copies or substantial portions of the Software.
  15 //
  16 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
  18 // THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  20 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  21 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  22 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23
  24 #ifndef _QCMS_TRANSFORM_UTIL_H
  25 #define _QCMS_TRANSFORM_UTIL_H
  26
  27 #include <stdlib.h>
  28
  29 #define CLU(table,x,y,z) table[(x*len + y*x_len + z*xy_len)*3]
  30
  31 //XXX: could use a bettername
  32 typedef uint16_t uint16_fract_t;
  33
  34 float lut_interp_linear(double value, uint16_t *table, int length);
  35 float lut_interp_linear_float(float value, float *table, int length);
  36 uint16_t lut_interp_linear16(uint16_t input_value, uint16_t *table, int length);
  37
  38
  39 static inline float lerp(float a, float b, float t)
  40 {
  41         return a*(1.f-t) + b*t;
  42 }
  43
  44 static inline unsigned char clamp_u8(float v)
  45 {
  46   if (v > 255.)
  47     return 255;
  48   else if (v < 0)
  49     return 0;
  50   else
  51     return floorf(v+.5);
  52 }
  53
  54 static inline float clamp_float(float a)
  55 {
  56   /* One would naturally write this function as the following:
  57   if (a > 1.)
  58     return 1.;
  59   else if (a < 0)
  60     return 0;
  61   else
  62     return a;
  63
  64   However, that version will let NaNs pass through which is undesirable
  65   for most consumers.
  66   */
  67
  68   if (a > 1.)
  69     return 1.;
  70   else if (a >= 0)
  71     return a;
  72   else // a < 0 or a is NaN
  73     return 0;
  74 }
  75
  76 static inline float u8Fixed8Number_to_float(uint16_t x)
  77 {
  78   // 0x0000 = 0.
  79   // 0x0100 = 1.
  80   // 0xffff = 255  + 255/256
  81   return x/256.;
  82 }
  83
  84 float *build_input_gamma_table(struct curveType *TRC);
  85 struct matrix build_colorant_matrix(qcms_profile *p);
  86 void build_output_lut(struct curveType *trc,
  87                       uint16_t **output_gamma_lut, size_t *output_gamma_lut_length);
  88
  89 struct matrix matrix_invert(struct matrix mat);
  90 qcms_bool compute_precache(struct curveType *trc, uint8_t *output);
  91
  92
  93 #endif