release/plugins/sequence/gamma.c

   1 /*
   2  * Gamma Correction Plugin (RGB Version) 0.01
   3  *
   4  * Copyright (c) 2005 Peter Schlaile
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17
  18 #include <math.h>
  19 #include "plugin.h"
  20 #include "util.h"
  21 #include <stdio.h>
  22
  23 #define alpha_epsilon 0.0001f
  24 char name[]= "Gamma Correction";
  25
  26 VarStruct varstr[]= {
  27         { NUMSLI|FLO, "St M:", 0.0,     -1.0,   1.0, "Setup Main"},
  28         { NUMSLI|FLO, "Gn M:",  1.0,    0.0,    10.0,"Gain Main"},
  29         { NUMSLI|FLO, "Ga M:", 1.0,     0.0,    10.0, "Gamma Main"},
  30
  31         { NUMSLI|FLO, "St R:", 0.0,     -1.0,   1.0, "Setup Red"},
  32         { NUMSLI|FLO, "Gn R:",  1.0,    0.0,    10.0,"Gain Red"},
  33         { NUMSLI|FLO, "Ga R:", 1.0,     0.0,    10.0, "Gamma Red"},
  34
  35         { NUMSLI|FLO, "St G:", 0.0,     -1.0,   1.0, "Setup Green"},
  36         { NUMSLI|FLO, "Gn G:",  1.0,    0.0,    10.0,"Gain Green"},
  37         { NUMSLI|FLO, "Ga G:", 1.0,     0.0,    10.0, "Gamma Green"},
  38
  39         { NUMSLI|FLO, "St B:", 0.0,     -1.0,   1.0, "Setup Blue"},
  40         { NUMSLI|FLO, "Gn B:",  1.0,    0.0,    10.0,"Gain Blue"},
  41         { NUMSLI|FLO, "Ga B:", 1.0,     0.0,    10.0, "Gamma Blue"},
  42 };
  43
  44 typedef struct Cast {
  45         float setup_m;
  46         float gain_m;
  47         float gamma_m;
  48
  49         float setup_r;
  50         float gain_r;
  51         float gamma_r;
  52
  53         float setup_g;
  54         float gain_g;
  55         float gamma_g;
  56
  57         float setup_b;
  58         float gain_b;
  59         float gamma_b;
  60 } Cast;
  61
  62 float cfra;
  63
  64 void plugin_seq_doit(Cast *, float, float, int, int, ImBuf *, ImBuf *, ImBuf *, ImBuf *);
  65
  66 int plugin_seq_getversion(void) { return B_PLUGIN_VERSION; }
  67 void plugin_but_changed(int but) {}
  68 void plugin_init() {}
  69
  70 void plugin_getinfo(PluginInfo *info)
  71 {
  72         info->name= name;
  73         info->nvars= sizeof(varstr)/sizeof(VarStruct);
  74         info->cfra= &cfra;
  75
  76         info->varstr= varstr;
  77
  78         info->init= plugin_init;
  79         info->seq_doit= (SeqDoit) plugin_seq_doit;
  80         info->callback= plugin_but_changed;
  81 }
  82
  83 static void make_gamma_table(float setup, float gain, float gamma,
  84                              unsigned char * table)
  85 {
  86         int y;
  87
  88         for (y = 0; y < 256; y++) {
  89                 float v = 1.0 * y / 255;
  90                 v += setup;
  91                 v *= gain;
  92                 v = pow(v, gamma);
  93                 if ( v > 1.0) {
  94                         v = 1.0;
  95                 } else if (v < 0.0) {
  96                         v = 0.0;
  97                 }
  98                 table[y] = v * 255;
  99         }
 100
 101 }
 102
 103
 104 void plugin_seq_doit(Cast *cast, float facf0, float facf1, int width,
 105         int height, ImBuf *ibuf1, ImBuf *ibuf2, ImBuf *out, ImBuf *use) {
 106         if (!out->rect_float)
 107         {
 108                 unsigned char *dest, *src1, *src2;
 109                 int x, y, c;
 110                 unsigned char gamma_table_m[256];
 111                 unsigned char gamma_table_r[256];
 112                 unsigned char gamma_table_g[256];
 113                 unsigned char gamma_table_b[256];
 114
 115                 if (!ibuf1) return;
 116
 117                 dest= (unsigned char *) out->rect;
 118                 src1= (unsigned char *) ibuf1->rect;
 119
 120                 make_gamma_table(cast->setup_m, cast->gain_m, cast->gamma_m,
 121                                  gamma_table_m);
 122                 make_gamma_table(cast->setup_r, cast->gain_r, cast->gamma_r,
 123                                  gamma_table_r);
 124                 make_gamma_table(cast->setup_g, cast->gain_g, cast->gamma_g,
 125                                  gamma_table_g);
 126                 make_gamma_table(cast->setup_b, cast->gain_b, cast->gamma_b,
 127                                  gamma_table_b);
 128
 129                 for (y = 0; y < height; y++) {
 130                         for (x = 0; x < width; x++) {
 131                                 *dest++ = gamma_table_r[gamma_table_m[*src1++]];
 132                                 *dest++ = gamma_table_g[gamma_table_m[*src1++]];
 133                                 *dest++ = gamma_table_b[gamma_table_m[*src1++]];
 134                                 dest++; src1++;
 135                         }
 136                 }
 137         }
 138         else
 139         {
 140                 float *i=ibuf1->rect_float;
 141                 float *o=out->rect_float;
 142                 unsigned int size=width*height;
 143                 unsigned int k;
 144                 float val_r[3]={cast->setup_r,cast->gain_r,cast->gamma_r};
 145                 float val_g[3]={cast->setup_g,cast->gain_g,cast->gamma_g};
 146                 float val_b[3]={cast->setup_b,cast->gain_b,cast->gamma_b};
 147                 float *vals[3]={val_r,val_g,val_b};
 148                 for (k=0;k<size;++k)
 149                 {
 150                         if (cast->gamma_m!=1.f || cast->setup_m!=0.f || cast->gain_m!=1.f)
 151                         {
 152                                 float alpha=CLAMP(i[3],0.f,1.f);
 153                                 if (alpha>alpha_epsilon) {
 154                                         int l;
 155                                         for (l=0;l<3;++l)
 156                                         {
 157                                                 float *val=vals[l];
 158                                                 o[l]=i[l]/alpha;
 159                                                 o[l]=pow((o[l]+cast->setup_m)*cast->gain_m,cast->gamma_m);
 160                                                 if (val[2]!=1.f || val[0]!=0.f || val[1]!=1.f)
 161                                                 {
 162                                                         o[l]=pow((o[l]+val[0])*val[1],val[2]);
 163                                                 }
 164                                                 o[l]*=alpha;
 165                                                 o[l]=CLAMP(o[l],0.f,1.f);
 166                                         }
 167                                 } else {
 168                                         o[0]=o[1]=o[2]=0.0;
 169                                 }
 170                                 o[3]=1.0;
 171                         }
 172                         else
 173                         {
 174                                 int l;
 175                                 for (l=0;l<3;++l)
 176                                         o[l]=CLAMP(i[l],0.f,1.f);
 177                                 o[3]=1.0;
 178                         }
 179                         i+=4;
 180                         o+=4;
 181                 }
 182         }
 183 }