Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2 | /* pngrtran.c - transforms the data in a row for PNG readers |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 3 | * |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 4 | * libpng 1.0.0a |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 5 | * For conditions of distribution and use, see copyright notice in png.h |
| 6 | * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. |
| 7 | * Copyright (c) 1996, 1997 Andreas Dilger |
Glenn Randers-Pehrson | 2687fcc | 1998-01-07 20:54:20 -0600 | [diff] [blame] | 8 | * Copyright (c) 1998, Glenn Randers-Pehrson |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 9 | * March 9, 1998 |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 10 | * |
| 11 | * This file contains functions optionally called by an application |
| 12 | * in order to tell libpng how to handle data when reading a PNG. |
| 13 | * Transformations which are used in both reading and writing are |
| 14 | * in pngtrans.c. |
| 15 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 16 | |
| 17 | #define PNG_INTERNAL |
| 18 | #include "png.h" |
| 19 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 20 | #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED |
| 21 | /* With these routines, we avoid an integer divide, which will be slower on |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 22 | * many machines. However, it does take more operations than the corresponding |
| 23 | * divide method, so it may be slower on some RISC systems. There are two |
| 24 | * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. |
Glenn Randers-Pehrson | 2687fcc | 1998-01-07 20:54:20 -0600 | [diff] [blame] | 25 | * |
| 26 | * Note that the rounding factors are NOT supposed to be the same! 128 and |
| 27 | * 32768 are correct for the NODIV code; 127 and 32767 are correct for the |
| 28 | * standard method. |
| 29 | * |
| 30 | * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 31 | */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 32 | |
Glenn Randers-Pehrson | 2687fcc | 1998-01-07 20:54:20 -0600 | [diff] [blame] | 33 | /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ |
| 34 | # define png_composite(composite, fg, alpha, bg) \ |
| 35 | { png_uint_16 temp = ((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
| 36 | (png_uint_16)(bg)*(png_uint_16)(255 - \ |
| 37 | (png_uint_16)(alpha)) + (png_uint_16)128); \ |
| 38 | (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } |
| 39 | # define png_composite_16(composite, fg, alpha, bg) \ |
| 40 | { png_uint_32 temp = ((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
| 41 | (png_uint_32)(bg)*(png_uint_32)(65535L - \ |
| 42 | (png_uint_32)(alpha)) + (png_uint_32)32768L); \ |
| 43 | (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 44 | |
Glenn Randers-Pehrson | 2687fcc | 1998-01-07 20:54:20 -0600 | [diff] [blame] | 45 | #else /* standard method using integer division */ |
| 46 | |
| 47 | /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */ |
| 48 | # define png_composite(composite, fg, alpha, bg) \ |
| 49 | (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
| 50 | (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ |
| 51 | (png_uint_16)127) / 255) |
| 52 | # define png_composite_16(composite, fg, alpha, bg) \ |
| 53 | (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
| 54 | (png_uint_32)(bg)*(png_uint_32)(65535L - (png_uint_32)(alpha)) + \ |
| 55 | (png_uint_32)32767) / (png_uint_32)65535L) |
| 56 | |
| 57 | #endif /* ?PNG_READ_COMPOSITE_NODIV_SUPPORTED */ |
| 58 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 59 | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 60 | /* Set the action on getting a CRC error for an ancillary or critical chunk. */ |
| 61 | void |
| 62 | png_set_crc_action(png_structp png_ptr, int crit_action, int ancil_action) |
| 63 | { |
| 64 | png_debug(1, "in png_set_crc_action\n"); |
| 65 | /* Tell libpng how we react to CRC errors in critical chunks */ |
| 66 | switch (crit_action) |
| 67 | { |
| 68 | case PNG_CRC_NO_CHANGE: /* leave setting as is */ |
| 69 | break; |
| 70 | case PNG_CRC_WARN_USE: /* warn/use data */ |
| 71 | png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; |
| 72 | png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE; |
| 73 | break; |
| 74 | case PNG_CRC_QUIET_USE: /* quiet/use data */ |
| 75 | png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; |
| 76 | png_ptr->flags |= PNG_FLAG_CRC_CRITICAL_USE | |
| 77 | PNG_FLAG_CRC_CRITICAL_IGNORE; |
| 78 | break; |
| 79 | case PNG_CRC_WARN_DISCARD: /* not a valid action for critical data */ |
| 80 | png_warning(png_ptr, "Can't discard critical data on CRC error."); |
| 81 | case PNG_CRC_ERROR_QUIT: /* error/quit */ |
| 82 | case PNG_CRC_DEFAULT: |
| 83 | default: |
| 84 | png_ptr->flags &= ~PNG_FLAG_CRC_CRITICAL_MASK; |
| 85 | break; |
| 86 | } |
| 87 | |
| 88 | switch (ancil_action) |
| 89 | { |
| 90 | case PNG_CRC_NO_CHANGE: /* leave setting as is */ |
| 91 | break; |
| 92 | case PNG_CRC_WARN_USE: /* warn/use data */ |
| 93 | png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; |
| 94 | png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE; |
| 95 | break; |
| 96 | case PNG_CRC_QUIET_USE: /* quiet/use data */ |
| 97 | png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; |
| 98 | png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_USE | |
| 99 | PNG_FLAG_CRC_ANCILLARY_NOWARN; |
| 100 | break; |
| 101 | case PNG_CRC_ERROR_QUIT: /* error/quit */ |
| 102 | png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; |
| 103 | png_ptr->flags |= PNG_FLAG_CRC_ANCILLARY_NOWARN; |
| 104 | break; |
| 105 | case PNG_CRC_WARN_DISCARD: /* warn/discard data */ |
| 106 | case PNG_CRC_DEFAULT: |
| 107 | default: |
| 108 | png_ptr->flags &= ~PNG_FLAG_CRC_ANCILLARY_MASK; |
| 109 | break; |
| 110 | } |
| 111 | } |
| 112 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 113 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 114 | /* handle alpha and tRNS via a background color */ |
| 115 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 116 | png_set_background(png_structp png_ptr, |
| 117 | png_color_16p background_color, int background_gamma_code, |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 118 | int need_expand, double background_gamma) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 119 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 120 | png_debug(1, "in png_set_background\n"); |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 121 | if (background_gamma_code == PNG_BACKGROUND_GAMMA_UNKNOWN) |
| 122 | { |
| 123 | png_warning(png_ptr, "Application must supply a known background gamma"); |
| 124 | return; |
| 125 | } |
| 126 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 127 | png_ptr->transformations |= PNG_BACKGROUND; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 128 | png_memcpy(&(png_ptr->background), background_color, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 129 | sizeof(png_color_16)); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 130 | png_ptr->background_gamma = (float)background_gamma; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 131 | png_ptr->background_gamma_type = (png_byte)(background_gamma_code); |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 132 | png_ptr->transformations |= (need_expand ? PNG_BACKGROUND_EXPAND : 0); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 133 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 134 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 135 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 136 | #if defined(PNG_READ_16_TO_8_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 137 | /* strip 16 bit depth files to 8 bit depth */ |
| 138 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 139 | png_set_strip_16(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 140 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 141 | png_debug(1, "in png_set_strip_16\n"); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 142 | png_ptr->transformations |= PNG_16_TO_8; |
| 143 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 144 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 145 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 146 | #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
| 147 | void |
| 148 | png_set_strip_alpha(png_structp png_ptr) |
| 149 | { |
| 150 | png_debug(1, "in png_set_strip_alpha\n"); |
| 151 | png_ptr->transformations |= PNG_STRIP_ALPHA; |
| 152 | } |
| 153 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 154 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 155 | #if defined(PNG_READ_DITHER_SUPPORTED) |
| 156 | /* Dither file to 8 bit. Supply a palette, the current number |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 157 | * of elements in the palette, the maximum number of elements |
| 158 | * allowed, and a histogram if possible. If the current number |
| 159 | * of colors is greater then the maximum number, the palette will be |
| 160 | * modified to fit in the maximum number. "full_dither" indicates |
| 161 | * whether we need a dithering cube set up for RGB images, or if we |
| 162 | * simply are reducing the number of colors in a paletted image. |
| 163 | */ |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 164 | |
| 165 | typedef struct png_dsort_struct |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 166 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 167 | struct png_dsort_struct FAR * next; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 168 | png_byte left; |
| 169 | png_byte right; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 170 | } png_dsort; |
| 171 | typedef png_dsort FAR * png_dsortp; |
| 172 | typedef png_dsort FAR * FAR * png_dsortpp; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 173 | |
| 174 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 175 | png_set_dither(png_structp png_ptr, png_colorp palette, |
| 176 | int num_palette, int maximum_colors, png_uint_16p histogram, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 177 | int full_dither) |
| 178 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 179 | png_debug(1, "in png_set_dither\n"); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 180 | png_ptr->transformations |= PNG_DITHER; |
| 181 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 182 | if (!full_dither) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 183 | { |
| 184 | int i; |
| 185 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 186 | png_ptr->dither_index = (png_bytep)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 187 | (png_uint_32)(num_palette * sizeof (png_byte))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 188 | for (i = 0; i < num_palette; i++) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 189 | png_ptr->dither_index[i] = (png_byte)i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 190 | } |
| 191 | |
| 192 | if (num_palette > maximum_colors) |
| 193 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 194 | if (histogram != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 195 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 196 | /* This is easy enough, just throw out the least used colors. |
| 197 | Perhaps not the best solution, but good enough. */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 198 | |
| 199 | int i; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 200 | png_bytep sort; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 201 | |
| 202 | /* initialize an array to sort colors */ |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 203 | sort = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_palette |
| 204 | * sizeof (png_byte))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 205 | |
| 206 | /* initialize the sort array */ |
| 207 | for (i = 0; i < num_palette; i++) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 208 | sort[i] = (png_byte)i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 209 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 210 | /* Find the least used palette entries by starting a |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 211 | bubble sort, and running it until we have sorted |
| 212 | out enough colors. Note that we don't care about |
| 213 | sorting all the colors, just finding which are |
| 214 | least used. */ |
| 215 | |
| 216 | for (i = num_palette - 1; i >= maximum_colors; i--) |
| 217 | { |
| 218 | int done; /* to stop early if the list is pre-sorted */ |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 219 | int j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 220 | |
| 221 | done = 1; |
| 222 | for (j = 0; j < i; j++) |
| 223 | { |
| 224 | if (histogram[sort[j]] < histogram[sort[j + 1]]) |
| 225 | { |
| 226 | png_byte t; |
| 227 | |
| 228 | t = sort[j]; |
| 229 | sort[j] = sort[j + 1]; |
| 230 | sort[j + 1] = t; |
| 231 | done = 0; |
| 232 | } |
| 233 | } |
| 234 | if (done) |
| 235 | break; |
| 236 | } |
| 237 | |
| 238 | /* swap the palette around, and set up a table, if necessary */ |
| 239 | if (full_dither) |
| 240 | { |
| 241 | int j; |
| 242 | |
| 243 | /* put all the useful colors within the max, but don't |
| 244 | move the others */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 245 | for (i = 0, j = num_palette; i < maximum_colors; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 246 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 247 | if ((int)sort[i] >= maximum_colors) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 248 | { |
| 249 | do |
| 250 | j--; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 251 | while ((int)sort[j] >= maximum_colors); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 252 | palette[i] = palette[j]; |
| 253 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 254 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 255 | } |
| 256 | else |
| 257 | { |
| 258 | int j; |
| 259 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 260 | /* move all the used colors inside the max limit, and |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 261 | develop a translation table */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 262 | for (i = 0, j = num_palette; i < maximum_colors; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 263 | { |
| 264 | /* only move the colors we need to */ |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 265 | if ((int)sort[i] >= maximum_colors) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 266 | { |
| 267 | png_color tmp_color; |
| 268 | |
| 269 | do |
| 270 | j--; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 271 | while ((int)sort[j] >= maximum_colors); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 272 | |
| 273 | tmp_color = palette[j]; |
| 274 | palette[j] = palette[i]; |
| 275 | palette[i] = tmp_color; |
| 276 | /* indicate where the color went */ |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 277 | png_ptr->dither_index[j] = (png_byte)i; |
| 278 | png_ptr->dither_index[i] = (png_byte)j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 279 | } |
| 280 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 281 | |
| 282 | /* find closest color for those colors we are not using */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 283 | for (i = 0; i < num_palette; i++) |
| 284 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 285 | if ((int)png_ptr->dither_index[i] >= maximum_colors) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 286 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 287 | int min_d, k, min_k, d_index; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 288 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 289 | /* find the closest color to one we threw out */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 290 | d_index = png_ptr->dither_index[i]; |
| 291 | min_d = PNG_COLOR_DIST(palette[d_index], palette[0]); |
| 292 | for (k = 1, min_k = 0; k < maximum_colors; k++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 293 | { |
| 294 | int d; |
| 295 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 296 | d = PNG_COLOR_DIST(palette[d_index], palette[k]); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 297 | |
| 298 | if (d < min_d) |
| 299 | { |
| 300 | min_d = d; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 301 | min_k = k; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 302 | } |
| 303 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 304 | /* point to closest color */ |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 305 | png_ptr->dither_index[i] = (png_byte)min_k; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 306 | } |
| 307 | } |
| 308 | } |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 309 | png_free(png_ptr, sort); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 310 | } |
| 311 | else |
| 312 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 313 | /* This is much harder to do simply (and quickly). Perhaps |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 314 | we need to go through a median cut routine, but those |
| 315 | don't always behave themselves with only a few colors |
| 316 | as input. So we will just find the closest two colors, |
| 317 | and throw out one of them (chosen somewhat randomly). |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 318 | [I don't understand this at all, so if someone wants to |
| 319 | work on improving it, be my guest - AED] |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 320 | */ |
| 321 | int i; |
| 322 | int max_d; |
| 323 | int num_new_palette; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 324 | png_dsortpp hash; |
| 325 | png_bytep index_to_palette; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 326 | /* where the original index currently is in the palette */ |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 327 | png_bytep palette_to_index; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 328 | /* which original index points to this palette color */ |
| 329 | |
| 330 | /* initialize palette index arrays */ |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 331 | index_to_palette = (png_bytep)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 332 | (png_uint_32)(num_palette * sizeof (png_byte))); |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 333 | palette_to_index = (png_bytep)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 334 | (png_uint_32)(num_palette * sizeof (png_byte))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 335 | |
| 336 | /* initialize the sort array */ |
| 337 | for (i = 0; i < num_palette; i++) |
| 338 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 339 | index_to_palette[i] = (png_byte)i; |
| 340 | palette_to_index[i] = (png_byte)i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 341 | } |
| 342 | |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 343 | hash = (png_dsortpp)png_malloc(png_ptr, (png_uint_32)(769 * |
| 344 | sizeof (png_dsortp))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 345 | for (i = 0; i < 769; i++) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 346 | hash[i] = NULL; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 347 | /* png_memset(hash, 0, 769 * sizeof (png_dsortp)); */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 348 | |
| 349 | num_new_palette = num_palette; |
| 350 | |
| 351 | /* initial wild guess at how far apart the farthest pixel |
| 352 | pair we will be eliminating will be. Larger |
| 353 | numbers mean more areas will be allocated, Smaller |
| 354 | numbers run the risk of not saving enough data, and |
| 355 | having to do this all over again. |
| 356 | |
| 357 | I have not done extensive checking on this number. |
| 358 | */ |
| 359 | max_d = 96; |
| 360 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 361 | while (num_new_palette > maximum_colors) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 362 | { |
| 363 | for (i = 0; i < num_new_palette - 1; i++) |
| 364 | { |
| 365 | int j; |
| 366 | |
| 367 | for (j = i + 1; j < num_new_palette; j++) |
| 368 | { |
| 369 | int d; |
| 370 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 371 | d = PNG_COLOR_DIST(palette[i], palette[j]); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 372 | |
| 373 | if (d <= max_d) |
| 374 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 375 | png_dsortp t; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 376 | |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 377 | t = (png_dsortp)png_malloc(png_ptr, (png_uint_32)(sizeof |
| 378 | (png_dsort))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 379 | t->next = hash[d]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 380 | t->left = (png_byte)i; |
| 381 | t->right = (png_byte)j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 382 | hash[d] = t; |
| 383 | } |
| 384 | } |
| 385 | } |
| 386 | |
| 387 | for (i = 0; i <= max_d; i++) |
| 388 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 389 | if (hash[i] != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 390 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 391 | png_dsortp p; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 392 | |
| 393 | for (p = hash[i]; p; p = p->next) |
| 394 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 395 | if ((int)index_to_palette[p->left] < num_new_palette && |
| 396 | (int)index_to_palette[p->right] < num_new_palette) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 397 | { |
| 398 | int j, next_j; |
| 399 | |
| 400 | if (num_new_palette & 1) |
| 401 | { |
| 402 | j = p->left; |
| 403 | next_j = p->right; |
| 404 | } |
| 405 | else |
| 406 | { |
| 407 | j = p->right; |
| 408 | next_j = p->left; |
| 409 | } |
| 410 | |
| 411 | num_new_palette--; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 412 | palette[index_to_palette[j]] = palette[num_new_palette]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 413 | if (!full_dither) |
| 414 | { |
| 415 | int k; |
| 416 | |
| 417 | for (k = 0; k < num_palette; k++) |
| 418 | { |
| 419 | if (png_ptr->dither_index[k] == |
| 420 | index_to_palette[j]) |
| 421 | png_ptr->dither_index[k] = |
| 422 | index_to_palette[next_j]; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 423 | if ((int)png_ptr->dither_index[k] == |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 424 | num_new_palette) |
| 425 | png_ptr->dither_index[k] = |
| 426 | index_to_palette[j]; |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | index_to_palette[palette_to_index[num_new_palette]] = |
| 431 | index_to_palette[j]; |
| 432 | palette_to_index[index_to_palette[j]] = |
| 433 | palette_to_index[num_new_palette]; |
| 434 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 435 | index_to_palette[j] = (png_byte)num_new_palette; |
| 436 | palette_to_index[num_new_palette] = (png_byte)j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 437 | } |
| 438 | if (num_new_palette <= maximum_colors) |
| 439 | break; |
| 440 | } |
| 441 | if (num_new_palette <= maximum_colors) |
| 442 | break; |
| 443 | } |
| 444 | } |
| 445 | |
| 446 | for (i = 0; i < 769; i++) |
| 447 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 448 | if (hash[i] != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 449 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 450 | png_dsortp p; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 451 | |
| 452 | p = hash[i]; |
| 453 | while (p) |
| 454 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 455 | png_dsortp t; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 456 | |
| 457 | t = p->next; |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 458 | png_free(png_ptr, p); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 459 | p = t; |
| 460 | } |
| 461 | } |
| 462 | hash[i] = 0; |
| 463 | } |
| 464 | max_d += 96; |
| 465 | } |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 466 | png_free(png_ptr, hash); |
| 467 | png_free(png_ptr, palette_to_index); |
| 468 | png_free(png_ptr, index_to_palette); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 469 | } |
| 470 | num_palette = maximum_colors; |
| 471 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 472 | if (png_ptr->palette == NULL) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 473 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 474 | png_ptr->palette = palette; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 475 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 476 | png_ptr->num_palette = (png_uint_16)num_palette; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 477 | |
| 478 | if (full_dither) |
| 479 | { |
| 480 | int i; |
| 481 | int total_bits, num_red, num_green, num_blue; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 482 | png_size_t num_entries; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 483 | png_bytep distance; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 484 | |
| 485 | total_bits = PNG_DITHER_RED_BITS + PNG_DITHER_GREEN_BITS + |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 486 | PNG_DITHER_BLUE_BITS; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 487 | |
| 488 | num_red = (1 << PNG_DITHER_RED_BITS); |
| 489 | num_green = (1 << PNG_DITHER_GREEN_BITS); |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 490 | num_blue = (1 << PNG_DITHER_BLUE_BITS); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 491 | num_entries = ((png_size_t)1 << total_bits); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 492 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 493 | png_ptr->palette_lookup = (png_bytep )png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 494 | (png_uint_32)(num_entries * sizeof (png_byte))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 495 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 496 | png_memset(png_ptr->palette_lookup, 0, num_entries * sizeof (png_byte)); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 497 | |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 498 | distance = (png_bytep)png_malloc(png_ptr, (png_uint_32)(num_entries * |
| 499 | sizeof(png_byte))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 500 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 501 | png_memset(distance, 0xff, num_entries * sizeof(png_byte)); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 502 | |
| 503 | for (i = 0; i < num_palette; i++) |
| 504 | { |
| 505 | int r, g, b, ir, ig, ib; |
| 506 | |
| 507 | r = (palette[i].red >> (8 - PNG_DITHER_RED_BITS)); |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 508 | g = (palette[i].green >> (8 - PNG_DITHER_GREEN_BITS)); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 509 | b = (palette[i].blue >> (8 - PNG_DITHER_BLUE_BITS)); |
| 510 | |
| 511 | for (ir = 0; ir < num_red; ir++) |
| 512 | { |
| 513 | int dr, index_r; |
| 514 | |
| 515 | dr = abs(ir - r); |
| 516 | index_r = (ir << (PNG_DITHER_BLUE_BITS + PNG_DITHER_GREEN_BITS)); |
| 517 | for (ig = 0; ig < num_green; ig++) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 518 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 519 | int dg, dt, dm, index_g; |
| 520 | |
| 521 | dg = abs(ig - g); |
| 522 | dt = dr + dg; |
| 523 | dm = ((dr > dg) ? dr : dg); |
| 524 | index_g = index_r | (ig << PNG_DITHER_BLUE_BITS); |
| 525 | for (ib = 0; ib < num_blue; ib++) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 526 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 527 | int d_index, db, dmax, d; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 528 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 529 | d_index = index_g | ib; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 530 | db = abs(ib - b); |
| 531 | dmax = ((dm > db) ? dm : db); |
| 532 | d = dmax + dt + db; |
| 533 | |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 534 | if (d < (int)distance[d_index]) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 535 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 536 | distance[d_index] = (png_byte)d; |
| 537 | png_ptr->palette_lookup[d_index] = (png_byte)i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 538 | } |
| 539 | } |
| 540 | } |
| 541 | } |
| 542 | } |
| 543 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 544 | png_free(png_ptr, distance); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 545 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 546 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 547 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 548 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 549 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 550 | /* Transform the image from the file_gamma to the screen_gamma. We |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 551 | * only do transformations on images where the file_gamma and screen_gamma |
| 552 | * are not close reciprocals, otherwise it slows things down slightly, and |
| 553 | * also needlessly introduces small errors. |
| 554 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 555 | void |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 556 | png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 557 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 558 | png_debug(1, "in png_set_gamma\n"); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 559 | if (fabs(scrn_gamma * file_gamma - 1.0) > PNG_GAMMA_THRESHOLD) |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 560 | png_ptr->transformations |= PNG_GAMMA; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 561 | png_ptr->gamma = (float)file_gamma; |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 562 | png_ptr->screen_gamma = (float)scrn_gamma; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 563 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 564 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 565 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 566 | #if defined(PNG_READ_EXPAND_SUPPORTED) |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 567 | /* Expand paletted images to rgb, expand grayscale images of |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 568 | * less then 8 bit depth to 8 bit depth, and expand tRNS chunks |
| 569 | * to alpha channels. |
| 570 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 571 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 572 | png_set_expand(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 573 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 574 | png_debug(1, "in png_set_expand\n"); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 575 | png_ptr->transformations |= PNG_EXPAND; |
| 576 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 577 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 578 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 579 | #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 580 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 581 | png_set_gray_to_rgb(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 582 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 583 | png_debug(1, "in png_set_gray_to_rgb\n"); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 584 | png_ptr->transformations |= PNG_GRAY_TO_RGB; |
| 585 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 586 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 587 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 588 | #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) |
| 589 | /* Convert a RGB image to a grayscale of the given width. This would |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 590 | * allow us, for example, to convert a 24 bpp RGB image into an 8 or |
| 591 | * 16 bpp grayscale image. (Not yet implemented.) |
| 592 | */ |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 593 | void |
| 594 | png_set_rgb_to_gray(png_structp png_ptr, int gray_bits) |
| 595 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 596 | png_debug(1, "in png_set_rgb_to_gray\n"); |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 597 | png_ptr->transformations |= PNG_RGB_TO_GRAY; |
| 598 | /* Need to do something with gray_bits here. */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 599 | png_warning(png_ptr, "RGB to GRAY transformation is not yet implemented."); |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 600 | } |
| 601 | #endif |
| 602 | |
Glenn Randers-Pehrson | 08a3343 | 1998-03-07 06:06:55 -0600 | [diff] [blame] | 603 | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) |
| 604 | void |
| 605 | png_set_read_user_transform_fn(png_structp png_ptr, png_user_transform_ptr |
| 606 | read_user_transform_fn) |
| 607 | { |
| 608 | png_debug(1, "in png_set_read_user_transform_fn\n"); |
| 609 | png_ptr->transformations |= PNG_USER_TRANSFORM; |
| 610 | png_ptr->read_user_transform_fn = read_user_transform_fn; |
| 611 | } |
| 612 | #endif |
| 613 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 614 | /* Initialize everything needed for the read. This includes modifying |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 615 | * the palette. |
| 616 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 617 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 618 | png_init_read_transformations(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 619 | { |
| 620 | int color_type; |
| 621 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 622 | png_debug(1, "in png_init_read_transformations\n"); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 623 | color_type = png_ptr->color_type; |
| 624 | |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 625 | #if defined(PNG_READ_EXPAND_SUPPORTED) && defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 626 | if (png_ptr->transformations & PNG_BACKGROUND_EXPAND) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 627 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 628 | if (color_type == PNG_COLOR_TYPE_GRAY) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 629 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 630 | /* expand background chunk. */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 631 | switch (png_ptr->bit_depth) |
| 632 | { |
| 633 | case 1: |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 634 | png_ptr->background.gray *= (png_uint_16)0xff; |
| 635 | png_ptr->background.red = png_ptr->background.green = |
| 636 | png_ptr->background.blue = png_ptr->background.gray; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 637 | break; |
| 638 | case 2: |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 639 | png_ptr->background.gray *= (png_uint_16)0x55; |
| 640 | png_ptr->background.red = png_ptr->background.green = |
| 641 | png_ptr->background.blue = png_ptr->background.gray; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 642 | break; |
| 643 | case 4: |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 644 | png_ptr->background.gray *= (png_uint_16)0x11; |
| 645 | png_ptr->background.red = png_ptr->background.green = |
| 646 | png_ptr->background.blue = png_ptr->background.gray; |
| 647 | break; |
| 648 | case 8: |
| 649 | case 16: |
| 650 | png_ptr->background.red = png_ptr->background.green = |
| 651 | png_ptr->background.blue = png_ptr->background.gray; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 652 | break; |
| 653 | } |
| 654 | } |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 655 | else if (color_type == PNG_COLOR_TYPE_PALETTE) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 656 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 657 | png_ptr->background.red = |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 658 | png_ptr->palette[png_ptr->background.index].red; |
| 659 | png_ptr->background.green = |
| 660 | png_ptr->palette[png_ptr->background.index].green; |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 661 | png_ptr->background.blue = |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 662 | png_ptr->palette[png_ptr->background.index].blue; |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 663 | |
| 664 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) |
| 665 | if (png_ptr->transformations & PNG_INVERT_ALPHA) |
| 666 | { |
| 667 | #if defined(PNG_READ_EXPAND_SUPPORTED) |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 668 | /* GRR BUG #1: was (png_ptr->transformations & !PNG_EXPAND) */ |
| 669 | if (!(png_ptr->transformations & PNG_EXPAND)) |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 670 | #endif |
| 671 | { |
| 672 | /* invert the alpha channel (in tRNS) unless the pixels are |
| 673 | going to be expanded, in which case leave it for later */ |
| 674 | int i; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 675 | for (i=0; i<(int)png_ptr->num_trans; i++) |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 676 | png_ptr->trans[i] = 255 - png_ptr->trans[i]; |
| 677 | } |
| 678 | } |
| 679 | #endif |
| 680 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 681 | } |
| 682 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 683 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 684 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 685 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 686 | png_ptr->background_1 = png_ptr->background; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 687 | #endif |
| 688 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 689 | if (png_ptr->transformations & PNG_GAMMA) |
| 690 | { |
| 691 | png_build_gamma_table(png_ptr); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 692 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 693 | if (png_ptr->transformations & PNG_BACKGROUND) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 694 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 695 | if (color_type == PNG_COLOR_TYPE_PALETTE) |
| 696 | { |
| 697 | int num_palette, i; |
| 698 | png_color back, back_1; |
| 699 | png_colorp palette; |
| 700 | |
| 701 | palette = png_ptr->palette; |
| 702 | num_palette = png_ptr->num_palette; |
| 703 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 704 | if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE) |
| 705 | { |
| 706 | back.red = png_ptr->gamma_table[png_ptr->background.red]; |
| 707 | back.green = png_ptr->gamma_table[png_ptr->background.green]; |
| 708 | back.blue = png_ptr->gamma_table[png_ptr->background.blue]; |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 709 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 710 | back_1.red = png_ptr->gamma_to_1[png_ptr->background.red]; |
| 711 | back_1.green = png_ptr->gamma_to_1[png_ptr->background.green]; |
| 712 | back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue]; |
| 713 | } |
| 714 | else |
| 715 | { |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 716 | double g, gs; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 717 | |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 718 | /* |
| 719 | GRR BUG #3: inconsistent with handling of full RGBA below |
| 720 | g = 1.0 / png_ptr->background_gamma; |
| 721 | gs = 1.0 / (png_ptr->background_gamma * png_ptr->screen_gamma); |
| 722 | */ |
| 723 | switch (png_ptr->background_gamma_type) |
Glenn Randers-Pehrson | 4922b1b | 1998-03-08 22:55:17 -0600 | [diff] [blame] | 724 | { |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 725 | case PNG_BACKGROUND_GAMMA_SCREEN: |
| 726 | g = (png_ptr->screen_gamma); |
| 727 | gs = 1.0; |
| 728 | break; |
| 729 | case PNG_BACKGROUND_GAMMA_FILE: |
| 730 | g = 1.0 / (png_ptr->gamma); |
| 731 | gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); |
| 732 | break; |
| 733 | case PNG_BACKGROUND_GAMMA_UNIQUE: |
| 734 | g = 1.0 / (png_ptr->background_gamma); |
| 735 | gs = 1.0 / (png_ptr->background_gamma * |
| 736 | png_ptr->screen_gamma); |
| 737 | break; |
| 738 | default: |
| 739 | g = 1.0; /* back_1 */ |
| 740 | gs = 1.0; /* back */ |
| 741 | } |
| 742 | |
| 743 | if ( |
| 744 | /* |
| 745 | GRR BUG #2: This creates self-inconsistent images--fully |
| 746 | transparent and fully opaque look fine, but translucent |
| 747 | pixels are wrong (too bright if XV's code can be trusted). |
| 748 | Commenting it out makes an internally self-consistent |
| 749 | image, but still not consistent with RGBA version of same |
| 750 | thing (again, too bright in XV). |
| 751 | png_ptr->background_gamma_type==PNG_BACKGROUND_GAMMA_SCREEN|| |
| 752 | */ |
| 753 | fabs(gs - 1.0) < PNG_GAMMA_THRESHOLD) |
| 754 | { |
| 755 | back.red = (png_byte)png_ptr->background.red; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 756 | back.green = (png_byte)png_ptr->background.green; |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 757 | back.blue = (png_byte)png_ptr->background.blue; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 758 | } |
| 759 | else |
| 760 | { |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 761 | back.red = (png_byte)(pow( |
| 762 | (double)png_ptr->background.red/255, gs) * 255.0 + .5); |
| 763 | back.green = (png_byte)(pow( |
| 764 | (double)png_ptr->background.green/255, gs) * 255.0 + .5); |
| 765 | back.blue = (png_byte)(pow( |
| 766 | (double)png_ptr->background.blue/255, gs) * 255.0 + .5); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 767 | } |
| 768 | |
Glenn Randers-Pehrson | 8f8fb6a | 1998-03-09 23:02:06 -0600 | [diff] [blame^] | 769 | back_1.red = (png_byte)(pow( |
| 770 | (double)png_ptr->background.red/255, g) * 255.0 + .5); |
| 771 | back_1.green = (png_byte)(pow( |
| 772 | (double)png_ptr->background.green/255, g) * 255.0 + .5); |
| 773 | back_1.blue = (png_byte)(pow( |
| 774 | (double)png_ptr->background.blue/255, g) * 255.0 + .5); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 775 | } |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 776 | |
| 777 | for (i = 0; i < num_palette; i++) |
| 778 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 779 | if (i < (int)png_ptr->num_trans && png_ptr->trans[i] != 0xff) |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 780 | { |
| 781 | if (png_ptr->trans[i] == 0) |
| 782 | { |
| 783 | palette[i] = back; |
| 784 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 785 | else /* if (png_ptr->trans[i] != 0xff) */ |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 786 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 787 | png_byte v, w; |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 788 | |
| 789 | v = png_ptr->gamma_to_1[palette[i].red]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 790 | png_composite(w, v, png_ptr->trans[i], back_1.red); |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 791 | palette[i].red = png_ptr->gamma_from_1[w]; |
| 792 | |
| 793 | v = png_ptr->gamma_to_1[palette[i].green]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 794 | png_composite(w, v, png_ptr->trans[i], back_1.green); |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 795 | palette[i].green = png_ptr->gamma_from_1[w]; |
| 796 | |
| 797 | v = png_ptr->gamma_to_1[palette[i].blue]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 798 | png_composite(w, v, png_ptr->trans[i], back_1.blue); |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 799 | palette[i].blue = png_ptr->gamma_from_1[w]; |
| 800 | } |
| 801 | } |
| 802 | else |
| 803 | { |
| 804 | palette[i].red = png_ptr->gamma_table[palette[i].red]; |
| 805 | palette[i].green = png_ptr->gamma_table[palette[i].green]; |
| 806 | palette[i].blue = png_ptr->gamma_table[palette[i].blue]; |
| 807 | } |
| 808 | } |
| 809 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 810 | /* if (png_ptr->background_gamma_type!=PNG_BACKGROUND_GAMMA_UNKNOWN)*/ |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 811 | else |
| 812 | /* color_type != PNG_COLOR_TYPE_PALETTE */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 813 | { |
| 814 | double g, gs, m; |
| 815 | |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 816 | m = (double)(((png_uint_32)1 << png_ptr->bit_depth) - 1); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 817 | g = 1.0; |
| 818 | gs = 1.0; |
| 819 | |
| 820 | switch (png_ptr->background_gamma_type) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 821 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 822 | case PNG_BACKGROUND_GAMMA_SCREEN: |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 823 | g = (png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 824 | gs = 1.0; |
| 825 | break; |
| 826 | case PNG_BACKGROUND_GAMMA_FILE: |
| 827 | g = 1.0 / (png_ptr->gamma); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 828 | gs = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 829 | break; |
| 830 | case PNG_BACKGROUND_GAMMA_UNIQUE: |
| 831 | g = 1.0 / (png_ptr->background_gamma); |
| 832 | gs = 1.0 / (png_ptr->background_gamma * |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 833 | png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 834 | break; |
| 835 | } |
| 836 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 837 | if (color_type & PNG_COLOR_MASK_COLOR) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 838 | { |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 839 | /* RGB or RGBA */ |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 840 | png_ptr->background_1.red = (png_uint_16)(pow( |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 841 | (double)png_ptr->background.red / m, g) * m + .5); |
| 842 | png_ptr->background_1.green = (png_uint_16)(pow( |
| 843 | (double)png_ptr->background.green / m, g) * m + .5); |
| 844 | png_ptr->background_1.blue = (png_uint_16)(pow( |
| 845 | (double)png_ptr->background.blue / m, g) * m + .5); |
| 846 | png_ptr->background.red = (png_uint_16)(pow( |
| 847 | (double)png_ptr->background.red / m, gs) * m + .5); |
| 848 | png_ptr->background.green = (png_uint_16)(pow( |
| 849 | (double)png_ptr->background.green / m, gs) * m + .5); |
| 850 | png_ptr->background.blue = (png_uint_16)(pow( |
| 851 | (double)png_ptr->background.blue / m, gs) * m + .5); |
| 852 | } |
| 853 | else |
| 854 | { |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 855 | /* GRAY or GRAY ALPHA */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 856 | png_ptr->background_1.gray = (png_uint_16)(pow( |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 857 | (double)png_ptr->background.gray / m, g) * m + .5); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 858 | png_ptr->background.gray = (png_uint_16)(pow( |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 859 | (double)png_ptr->background.gray / m, gs) * m + .5); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 860 | } |
| 861 | } |
| 862 | } |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 863 | else |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 864 | /* transformation does not include PNG_BACKGROUND */ |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 865 | #endif |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 866 | if (color_type == PNG_COLOR_TYPE_PALETTE) |
| 867 | { |
| 868 | int num_palette, i; |
| 869 | png_colorp palette; |
| 870 | |
| 871 | palette = png_ptr->palette; |
| 872 | num_palette = png_ptr->num_palette; |
| 873 | |
| 874 | for (i = 0; i < num_palette; i++) |
| 875 | { |
| 876 | palette[i].red = png_ptr->gamma_table[palette[i].red]; |
| 877 | palette[i].green = png_ptr->gamma_table[palette[i].green]; |
| 878 | palette[i].blue = png_ptr->gamma_table[palette[i].blue]; |
| 879 | } |
| 880 | } |
| 881 | } |
| 882 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 883 | else |
| 884 | #endif |
| 885 | #endif |
| 886 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 887 | /* No GAMMA transformation */ |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 888 | if (png_ptr->transformations & PNG_BACKGROUND && |
| 889 | color_type == PNG_COLOR_TYPE_PALETTE) |
| 890 | { |
| 891 | int i; |
| 892 | png_color back; |
| 893 | png_colorp palette; |
| 894 | |
| 895 | palette = png_ptr->palette; |
| 896 | back.red = (png_byte)png_ptr->background.red; |
| 897 | back.green = (png_byte)png_ptr->background.green; |
| 898 | back.blue = (png_byte)png_ptr->background.blue; |
| 899 | |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 900 | for (i = 0; i < (int)png_ptr->num_trans; i++) |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 901 | { |
| 902 | if (png_ptr->trans[i] == 0) |
| 903 | { |
| 904 | palette[i] = back; |
| 905 | } |
| 906 | else if (png_ptr->trans[i] != 0xff) |
| 907 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 908 | png_composite(palette[i].red, palette[i].red, |
| 909 | png_ptr->trans[i], back.red); |
| 910 | png_composite(palette[i].green, palette[i].green, |
| 911 | png_ptr->trans[i], back.green); |
| 912 | png_composite(palette[i].blue, palette[i].blue, |
| 913 | png_ptr->trans[i], back.blue); |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 914 | } |
| 915 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 916 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 917 | #endif |
| 918 | |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 919 | #if defined(PNG_READ_SHIFT_SUPPORTED) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 920 | if ((png_ptr->transformations & PNG_SHIFT) && |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 921 | color_type == PNG_COLOR_TYPE_PALETTE) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 922 | { |
| 923 | png_uint_16 i; |
| 924 | int sr, sg, sb; |
| 925 | |
| 926 | sr = 8 - png_ptr->sig_bit.red; |
| 927 | if (sr < 0 || sr > 8) |
| 928 | sr = 0; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 929 | sg = 8 - png_ptr->sig_bit.green; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 930 | if (sg < 0 || sg > 8) |
| 931 | sg = 0; |
| 932 | sb = 8 - png_ptr->sig_bit.blue; |
| 933 | if (sb < 0 || sb > 8) |
| 934 | sb = 0; |
| 935 | for (i = 0; i < png_ptr->num_palette; i++) |
| 936 | { |
| 937 | png_ptr->palette[i].red >>= sr; |
| 938 | png_ptr->palette[i].green >>= sg; |
| 939 | png_ptr->palette[i].blue >>= sb; |
| 940 | } |
| 941 | } |
| 942 | #endif |
| 943 | } |
| 944 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 945 | /* Modify the info structure to reflect the transformations. The |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 946 | * info should be updated so a PNG file could be written with it, |
| 947 | * assuming the transformations result in valid PNG data. |
| 948 | */ |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 949 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 950 | png_read_transform_info(png_structp png_ptr, png_infop info_ptr) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 951 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 952 | png_debug(1, "in png_read_transform_info\n"); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 953 | #if defined(PNG_READ_EXPAND_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 954 | if (png_ptr->transformations & PNG_EXPAND) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 955 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 956 | if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
| 957 | { |
| 958 | if (png_ptr->num_trans) |
| 959 | info_ptr->color_type = PNG_COLOR_TYPE_RGB_ALPHA; |
| 960 | else |
| 961 | info_ptr->color_type = PNG_COLOR_TYPE_RGB; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 962 | info_ptr->bit_depth = 8; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 963 | info_ptr->num_trans = 0; |
| 964 | } |
| 965 | else |
| 966 | { |
| 967 | if (png_ptr->num_trans) |
| 968 | info_ptr->color_type |= PNG_COLOR_MASK_ALPHA; |
| 969 | if (info_ptr->bit_depth < 8) |
| 970 | info_ptr->bit_depth = 8; |
| 971 | info_ptr->num_trans = 0; |
| 972 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 973 | } |
| 974 | #endif |
| 975 | |
| 976 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 977 | if (png_ptr->transformations & PNG_BACKGROUND) |
| 978 | { |
| 979 | info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA; |
| 980 | info_ptr->num_trans = 0; |
| 981 | info_ptr->background = png_ptr->background; |
| 982 | } |
| 983 | #endif |
| 984 | |
| 985 | #if defined(PNG_READ_16_TO_8_SUPPORTED) |
| 986 | if ((png_ptr->transformations & PNG_16_TO_8) && info_ptr->bit_depth == 16) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 987 | info_ptr->bit_depth = 8; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 988 | #endif |
| 989 | |
| 990 | #if defined(PNG_READ_DITHER_SUPPORTED) |
| 991 | if (png_ptr->transformations & PNG_DITHER) |
| 992 | { |
| 993 | if (((info_ptr->color_type == PNG_COLOR_TYPE_RGB) || |
| 994 | (info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)) && |
| 995 | png_ptr->palette_lookup && info_ptr->bit_depth == 8) |
| 996 | { |
| 997 | info_ptr->color_type = PNG_COLOR_TYPE_PALETTE; |
| 998 | } |
| 999 | } |
| 1000 | #endif |
| 1001 | |
| 1002 | #if defined(PNG_READ_PACK_SUPPORTED) |
| 1003 | if ((png_ptr->transformations & PNG_PACK) && info_ptr->bit_depth < 8) |
| 1004 | info_ptr->bit_depth = 8; |
| 1005 | #endif |
| 1006 | |
| 1007 | #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) |
| 1008 | if ((png_ptr->transformations & PNG_GRAY_TO_RGB) && |
| 1009 | !(info_ptr->color_type & PNG_COLOR_MASK_COLOR)) |
| 1010 | info_ptr->color_type |= PNG_COLOR_MASK_COLOR; |
| 1011 | #endif |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1012 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1013 | if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1014 | info_ptr->channels = 1; |
| 1015 | else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR) |
| 1016 | info_ptr->channels = 3; |
| 1017 | else |
| 1018 | info_ptr->channels = 1; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1019 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1020 | #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1021 | if ((png_ptr->transformations & PNG_STRIP_ALPHA) && |
| 1022 | info_ptr->color_type & PNG_COLOR_MASK_ALPHA) |
| 1023 | { |
| 1024 | info_ptr->channels--; |
| 1025 | info_ptr->color_type &= ~PNG_COLOR_MASK_ALPHA; |
| 1026 | } |
| 1027 | #endif |
| 1028 | |
| 1029 | #if defined(PNG_READ_FILLER_SUPPORTED) |
| 1030 | if ((png_ptr->transformations & PNG_FILLER) && |
| 1031 | info_ptr->color_type & PNG_COLOR_TYPE_RGB && |
| 1032 | info_ptr->channels == 3) |
| 1033 | { |
| 1034 | info_ptr->channels = 4; |
| 1035 | } |
| 1036 | #endif |
| 1037 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1038 | if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) |
| 1039 | info_ptr->channels++; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1040 | info_ptr->pixel_depth = (png_byte)(info_ptr->channels * |
| 1041 | info_ptr->bit_depth); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1042 | |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1043 | info_ptr->rowbytes = ((info_ptr->width * info_ptr->pixel_depth + 7) >> 3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1044 | } |
| 1045 | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 1046 | /* Transform the row. The order of transformations is significant, |
| 1047 | * and is very touchy. If you add a transformation, take care to |
| 1048 | * decide how it fits in with the other transformations here. |
| 1049 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1050 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1051 | png_do_read_transformations(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1052 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1053 | png_debug(1, "in png_do_read_transformations\n"); |
| 1054 | #if !defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1055 | if (png_ptr->row_buf == NULL) |
| 1056 | { |
Glenn Randers-Pehrson | 70e3f54 | 1998-01-03 22:40:55 -0600 | [diff] [blame] | 1057 | #if !defined(PNG_NO_STDIO) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1058 | char msg[50]; |
| 1059 | |
| 1060 | sprintf(msg, "NULL row buffer for row %ld, pass %d", png_ptr->row_number, |
| 1061 | png_ptr->pass); |
| 1062 | png_error(png_ptr, msg); |
Glenn Randers-Pehrson | 70e3f54 | 1998-01-03 22:40:55 -0600 | [diff] [blame] | 1063 | #else |
| 1064 | png_error(png_ptr, "NULL row buffer"); |
| 1065 | #endif |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1066 | } |
| 1067 | #endif |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 1068 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1069 | #if defined(PNG_READ_EXPAND_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1070 | if (png_ptr->transformations & PNG_EXPAND) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1071 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1072 | if (png_ptr->row_info.color_type == PNG_COLOR_TYPE_PALETTE) |
| 1073 | { |
| 1074 | png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1075 | png_ptr->palette, png_ptr->trans, png_ptr->num_trans); |
| 1076 | } |
| 1077 | else if (png_ptr->transformations & PNG_EXPAND) |
| 1078 | { |
| 1079 | if (png_ptr->num_trans) |
| 1080 | png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1081 | &(png_ptr->trans_values)); |
| 1082 | else |
| 1083 | png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1084 | NULL); |
| 1085 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1086 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1087 | #endif |
| 1088 | |
| 1089 | #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
| 1090 | if (png_ptr->transformations & PNG_STRIP_ALPHA) |
| 1091 | png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1092 | PNG_FLAG_FILLER_AFTER); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1093 | #endif |
| 1094 | |
| 1095 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 1096 | if ((png_ptr->transformations & PNG_BACKGROUND) && |
| 1097 | ((png_ptr->num_trans != 0 ) || |
| 1098 | (png_ptr->color_type & PNG_COLOR_MASK_ALPHA))) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1099 | png_do_background(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1100 | &(png_ptr->trans_values), &(png_ptr->background), |
| 1101 | &(png_ptr->background_1), |
| 1102 | png_ptr->gamma_table, png_ptr->gamma_from_1, |
| 1103 | png_ptr->gamma_to_1, png_ptr->gamma_16_table, |
| 1104 | png_ptr->gamma_16_from_1, png_ptr->gamma_16_to_1, |
| 1105 | png_ptr->gamma_shift); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1106 | #endif |
| 1107 | |
| 1108 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
| 1109 | if ((png_ptr->transformations & PNG_GAMMA) && |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 1110 | !(png_ptr->transformations & PNG_BACKGROUND) && |
| 1111 | (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1112 | png_do_gamma(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1113 | png_ptr->gamma_table, png_ptr->gamma_16_table, |
| 1114 | png_ptr->gamma_shift); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1115 | #endif |
| 1116 | |
Glenn Randers-Pehrson | 08a3343 | 1998-03-07 06:06:55 -0600 | [diff] [blame] | 1117 | #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED) |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 1118 | if (png_ptr->transformations & PNG_RGB_TO_GRAY) |
| 1119 | png_do_rgb_to_gray(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 1120 | #endif |
| 1121 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1122 | #if defined(PNG_READ_16_TO_8_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1123 | if (png_ptr->transformations & PNG_16_TO_8) |
| 1124 | png_do_chop(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1125 | #endif |
| 1126 | |
| 1127 | #if defined(PNG_READ_DITHER_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1128 | if (png_ptr->transformations & PNG_DITHER) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1129 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1130 | png_do_dither((png_row_infop)&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1131 | png_ptr->palette_lookup, png_ptr->dither_index); |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1132 | if(png_ptr->row_info.rowbytes == (png_uint_32)0) |
| 1133 | png_error(png_ptr, "png_do_dither returned rowbytes=0"); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1134 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1135 | #endif |
| 1136 | |
| 1137 | #if defined(PNG_READ_INVERT_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1138 | if (png_ptr->transformations & PNG_INVERT_MONO) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1139 | png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1140 | #endif |
| 1141 | |
| 1142 | #if defined(PNG_READ_SHIFT_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1143 | if (png_ptr->transformations & PNG_SHIFT) |
| 1144 | png_do_unshift(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 1145 | &(png_ptr->shift)); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1146 | #endif |
| 1147 | |
| 1148 | #if defined(PNG_READ_PACK_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1149 | if (png_ptr->transformations & PNG_PACK) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1150 | png_do_unpack(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1151 | #endif |
| 1152 | |
| 1153 | #if defined(PNG_READ_BGR_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1154 | if (png_ptr->transformations & PNG_BGR) |
| 1155 | png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1156 | #endif |
| 1157 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1158 | #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
| 1159 | if (png_ptr->transformations & PNG_PACKSWAP) |
| 1160 | png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 1161 | #endif |
| 1162 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1163 | #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1164 | if (png_ptr->transformations & PNG_GRAY_TO_RGB) |
| 1165 | png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1166 | #endif |
| 1167 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1168 | #if defined(PNG_READ_FILLER_SUPPORTED) |
| 1169 | if (png_ptr->transformations & PNG_FILLER) |
| 1170 | png_do_read_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1171 | (png_uint_32)png_ptr->filler, png_ptr->flags); |
| 1172 | #endif |
| 1173 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1174 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) |
| 1175 | if (png_ptr->transformations & PNG_INVERT_ALPHA) |
| 1176 | png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 1177 | #endif |
| 1178 | |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1179 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) |
| 1180 | if (png_ptr->transformations & PNG_SWAP_ALPHA) |
| 1181 | png_do_read_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 1182 | #endif |
| 1183 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1184 | #if defined(PNG_READ_SWAP_SUPPORTED) |
| 1185 | if (png_ptr->transformations & PNG_SWAP_BYTES) |
| 1186 | png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1187 | #endif |
Glenn Randers-Pehrson | 08a3343 | 1998-03-07 06:06:55 -0600 | [diff] [blame] | 1188 | |
| 1189 | #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) |
| 1190 | if (png_ptr->transformations & PNG_USER_TRANSFORM) |
| 1191 | if(png_ptr->read_user_transform_fn != NULL) |
| 1192 | (*(png_ptr->read_user_transform_fn)) /* user read transform function */ |
| 1193 | (png_ptr, /* png_ptr */ |
| 1194 | &(png_ptr->row_info), /* row_info: */ |
| 1195 | /* png_uint_32 width; width of row */ |
| 1196 | /* png_uint_32 rowbytes; number of bytes in row */ |
| 1197 | /* png_byte color_type; color type of pixels */ |
| 1198 | /* png_byte bit_depth; bit depth of samples */ |
| 1199 | /* png_byte channels; number of channels (1-4) */ |
| 1200 | /* png_byte pixel_depth; bits per pixel (depth*channels) */ |
| 1201 | png_ptr->row_buf + 1); /* start of pixel data for row */ |
| 1202 | #endif |
| 1203 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1204 | } |
| 1205 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1206 | #if defined(PNG_READ_PACK_SUPPORTED) |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 1207 | /* Unpack pixels of 1, 2, or 4 bits per pixel into 1 byte per pixel, |
| 1208 | * without changing the actual values. Thus, if you had a row with |
| 1209 | * a bit depth of 1, you would end up with bytes that only contained |
| 1210 | * the numbers 0 or 1. If you would rather they contain 0 and 255, use |
| 1211 | * png_do_shift() after this. |
| 1212 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1213 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1214 | png_do_unpack(png_row_infop row_info, png_bytep row) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1215 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1216 | png_debug(1, "in png_do_unpack\n"); |
| 1217 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1218 | if (row != NULL && row_info != NULL && row_info->bit_depth < 8) |
| 1219 | #else |
| 1220 | if (row_info->bit_depth < 8) |
| 1221 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1222 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1223 | png_uint_32 shift, i; |
| 1224 | png_bytep sp, dp; |
| 1225 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1226 | switch (row_info->bit_depth) |
| 1227 | { |
| 1228 | case 1: |
| 1229 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1230 | sp = row + (png_size_t)((row_info->width - 1) >> 3); |
| 1231 | dp = row + (png_size_t)row_info->width - 1; |
| 1232 | shift = 7 - (int)((row_info->width + 7) & 7); |
| 1233 | for (i = 0; i < row_info->width; i++) |
| 1234 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1235 | *dp = (png_byte)((*sp >> shift) & 0x1); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1236 | if (shift == 7) |
| 1237 | { |
| 1238 | shift = 0; |
| 1239 | sp--; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1240 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1241 | else |
| 1242 | shift++; |
| 1243 | |
| 1244 | dp--; |
| 1245 | } |
| 1246 | break; |
| 1247 | } |
| 1248 | case 2: |
| 1249 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1250 | |
| 1251 | sp = row + (png_size_t)((row_info->width - 1) >> 2); |
| 1252 | dp = row + (png_size_t)row_info->width - 1; |
| 1253 | shift = (int)((3 - ((row_info->width + 3) & 3)) << 1); |
| 1254 | for (i = 0; i < row_info->width; i++) |
| 1255 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1256 | *dp = (png_byte)((*sp >> shift) & 0x3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1257 | if (shift == 6) |
| 1258 | { |
| 1259 | shift = 0; |
| 1260 | sp--; |
| 1261 | } |
| 1262 | else |
| 1263 | shift += 2; |
| 1264 | |
| 1265 | dp--; |
| 1266 | } |
| 1267 | break; |
| 1268 | } |
| 1269 | case 4: |
| 1270 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1271 | sp = row + (png_size_t)((row_info->width - 1) >> 1); |
| 1272 | dp = row + (png_size_t)row_info->width - 1; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1273 | shift = (int)((1 - ((row_info->width + 1) & 1)) << 2); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1274 | for (i = 0; i < row_info->width; i++) |
| 1275 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1276 | *dp = (png_byte)((*sp >> shift) & 0xf); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1277 | if (shift == 4) |
| 1278 | { |
| 1279 | shift = 0; |
| 1280 | sp--; |
| 1281 | } |
| 1282 | else |
| 1283 | shift = 4; |
| 1284 | |
| 1285 | dp--; |
| 1286 | } |
| 1287 | break; |
| 1288 | } |
| 1289 | } |
| 1290 | row_info->bit_depth = 8; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1291 | row_info->pixel_depth = (png_byte)(8 * row_info->channels); |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1292 | row_info->rowbytes = row_info->width * row_info->channels; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1293 | } |
| 1294 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1295 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1296 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1297 | #if defined(PNG_READ_SHIFT_SUPPORTED) |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 1298 | /* Reverse the effects of png_do_shift. This routine merely shifts the |
| 1299 | * pixels back to their significant bits values. Thus, if you have |
| 1300 | * a row of bit depth 8, but only 5 are significant, this will shift |
| 1301 | * the values back to 0 through 31. |
| 1302 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1303 | void |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1304 | png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1305 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1306 | png_debug(1, "in png_do_unshift\n"); |
| 1307 | if ( |
| 1308 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1309 | row != NULL && row_info != NULL && sig_bits != NULL && |
| 1310 | #endif |
| 1311 | row_info->color_type != PNG_COLOR_TYPE_PALETTE) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1312 | { |
| 1313 | int shift[4]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1314 | int channels, c; |
| 1315 | png_uint_16 value; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1316 | |
| 1317 | channels = 0; |
| 1318 | if (row_info->color_type & PNG_COLOR_MASK_COLOR) |
| 1319 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1320 | shift[channels++] = row_info->bit_depth - sig_bits->red; |
| 1321 | shift[channels++] = row_info->bit_depth - sig_bits->green; |
| 1322 | shift[channels++] = row_info->bit_depth - sig_bits->blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1323 | } |
| 1324 | else |
| 1325 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1326 | shift[channels++] = row_info->bit_depth - sig_bits->gray; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1327 | } |
| 1328 | if (row_info->color_type & PNG_COLOR_MASK_ALPHA) |
| 1329 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1330 | shift[channels++] = row_info->bit_depth - sig_bits->alpha; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1331 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1332 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1333 | value = 0; |
Guy Schalnat | 0f71645 | 1995-11-28 11:22:13 -0600 | [diff] [blame] | 1334 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1335 | for (c = 0; c < channels; c++) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1336 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1337 | if (shift[c] <= 0) |
| 1338 | shift[c] = 0; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1339 | else |
| 1340 | value = 1; |
| 1341 | } |
Guy Schalnat | 0f71645 | 1995-11-28 11:22:13 -0600 | [diff] [blame] | 1342 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1343 | if (!value) |
| 1344 | return; |
Guy Schalnat | 0f71645 | 1995-11-28 11:22:13 -0600 | [diff] [blame] | 1345 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1346 | switch (row_info->bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1347 | { |
| 1348 | case 2: |
| 1349 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1350 | png_bytep bp; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1351 | png_uint_32 i; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1352 | |
| 1353 | for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1354 | { |
| 1355 | *bp >>= 1; |
| 1356 | *bp &= 0x55; |
| 1357 | } |
| 1358 | break; |
| 1359 | } |
| 1360 | case 4: |
| 1361 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1362 | png_bytep bp; |
| 1363 | png_byte mask; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1364 | png_uint_32 i; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1365 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1366 | mask = (png_byte)(((int)0xf0 >> shift[0]) & (int)0xf0) | |
| 1367 | (png_byte)((int)0xf >> shift[0]); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1368 | for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1369 | { |
| 1370 | *bp >>= shift[0]; |
| 1371 | *bp &= mask; |
| 1372 | } |
| 1373 | break; |
| 1374 | } |
| 1375 | case 8: |
| 1376 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1377 | png_bytep bp; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1378 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1379 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1380 | for (bp = row, i = 0; i < row_info->width; i++) |
| 1381 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1382 | for (c = 0; c < (int)row_info->channels; c++, bp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1383 | { |
| 1384 | *bp >>= shift[c]; |
| 1385 | } |
| 1386 | } |
| 1387 | break; |
| 1388 | } |
| 1389 | case 16: |
| 1390 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1391 | png_bytep bp; |
| 1392 | png_size_t i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1393 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1394 | for (bp = row, i = 0; i < row_info->width; i++) |
| 1395 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1396 | for (c = 0; c < (int)row_info->channels; c++, bp += 2) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1397 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1398 | value = (png_uint_16)((*bp << 8) + *(bp + 1)); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1399 | value >>= shift[c]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1400 | *bp = (png_byte)(value >> 8); |
Guy Schalnat | 4ee97b0 | 1996-01-16 01:51:56 -0600 | [diff] [blame] | 1401 | *(bp + 1) = (png_byte)(value & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1402 | } |
| 1403 | } |
| 1404 | break; |
| 1405 | } |
| 1406 | } |
| 1407 | } |
| 1408 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1409 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1410 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1411 | #if defined(PNG_READ_16_TO_8_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1412 | /* chop rows of bit depth 16 down to 8 */ |
| 1413 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1414 | png_do_chop(png_row_infop row_info, png_bytep row) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1415 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1416 | png_debug(1, "in png_do_chop\n"); |
| 1417 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1418 | if (row != NULL && row_info != NULL && row_info->bit_depth == 16) |
| 1419 | #else |
| 1420 | if (row_info->bit_depth == 16) |
| 1421 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1422 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1423 | png_bytep sp, dp; |
| 1424 | png_uint_32 i; |
| 1425 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1426 | sp = row; |
| 1427 | dp = row; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1428 | for (i = 0; i < row_info->width * row_info->channels; i++, sp += 2, dp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1429 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1430 | #if defined(PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED) |
| 1431 | /* This does a more accurate scaling of the 16-bit color |
| 1432 | * value, rather than a simple low-byte truncation. |
| 1433 | * |
| 1434 | * What the ideal calculation should be: |
| 1435 | *dp = (((((png_uint_32)(*sp) << 8) | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 1436 | (png_uint_32)(*(sp + 1))) * 255 + 127) / (png_uint_32)65535L; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1437 | |
Glenn Randers-Pehrson | 2687fcc | 1998-01-07 20:54:20 -0600 | [diff] [blame] | 1438 | |
| 1439 | * GRR: no, I think this is what it really should be: |
| 1440 | *dp = (((((png_uint_32)(*sp) << 8) | |
| 1441 | (png_uint_32)(*(sp + 1))) + 128L) / (png_uint_32)257L; |
| 1442 | |
| 1443 | * GRR: here's the exact calculation with shifts: |
| 1444 | temp = (((png_uint_32)(*sp) << 8) | (png_uint_32)(*(sp + 1))) + 128L; |
| 1445 | *dp = (temp - (temp >> 8)) >> 8; |
| 1446 | |
| 1447 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1448 | * Approximate calculation with shift/add instead of multiply/divide: |
| 1449 | *dp = ((((png_uint_32)(*sp) << 8) | |
| 1450 | (png_uint_32)((int)(*(sp + 1)) - *sp)) + 128) >> 8; |
| 1451 | |
| 1452 | * What we actually do to avoid extra shifting and conversion: */ |
| 1453 | *dp = *sp + ((((int)(*(sp + 1)) - *sp) > 128) ? 1 : 0); |
| 1454 | #else |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1455 | *dp = *sp; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1456 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1457 | } |
| 1458 | row_info->bit_depth = 8; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1459 | row_info->pixel_depth = (png_byte)(8 * row_info->channels); |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1460 | row_info->rowbytes = row_info->width * row_info->channels; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1461 | } |
| 1462 | } |
| 1463 | #endif |
| 1464 | |
| 1465 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) |
| 1466 | void |
| 1467 | png_do_read_swap_alpha(png_row_infop row_info, png_bytep row) |
| 1468 | { |
| 1469 | png_debug(1, "in png_do_read_swap_alpha\n"); |
| 1470 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1471 | if (row != NULL && row_info != NULL) |
| 1472 | #endif |
| 1473 | { |
| 1474 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| 1475 | { |
| 1476 | /* This converts from RGBA to ARGB */ |
| 1477 | if (row_info->bit_depth == 8) |
| 1478 | { |
| 1479 | png_bytep sp, dp; |
| 1480 | png_byte save; |
| 1481 | png_uint_32 i; |
| 1482 | |
| 1483 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1484 | i < row_info->width; i++) |
| 1485 | { |
| 1486 | save = *(--sp); |
| 1487 | *(--dp) = *(--sp); |
| 1488 | *(--dp) = *(--sp); |
| 1489 | *(--dp) = *(--sp); |
| 1490 | *(--dp) = save; |
| 1491 | } |
| 1492 | } |
| 1493 | /* This converts from RRGGBBAA to AARRGGBB */ |
| 1494 | else |
| 1495 | { |
| 1496 | png_bytep sp, dp; |
| 1497 | png_byte save[2]; |
| 1498 | png_uint_32 i; |
| 1499 | |
| 1500 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1501 | i < row_info->width; i++) |
| 1502 | { |
| 1503 | save[0] = *(--sp); |
| 1504 | save[1] = *(--sp); |
| 1505 | *(--dp) = *(--sp); |
| 1506 | *(--dp) = *(--sp); |
| 1507 | *(--dp) = *(--sp); |
| 1508 | *(--dp) = *(--sp); |
| 1509 | *(--dp) = *(--sp); |
| 1510 | *(--dp) = *(--sp); |
| 1511 | *(--dp) = save[0]; |
| 1512 | *(--dp) = save[1]; |
| 1513 | } |
| 1514 | } |
| 1515 | } |
| 1516 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
| 1517 | { |
| 1518 | /* This converts from GA to AG */ |
| 1519 | if (row_info->bit_depth == 8) |
| 1520 | { |
| 1521 | png_bytep sp, dp; |
| 1522 | png_byte save; |
| 1523 | png_uint_32 i; |
| 1524 | |
| 1525 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1526 | i < row_info->width; i++) |
| 1527 | { |
| 1528 | save = *(--sp); |
| 1529 | *(--dp) = *(--sp); |
| 1530 | *(--dp) = save; |
| 1531 | } |
| 1532 | } |
| 1533 | /* This converts from GGAA to AAGG */ |
| 1534 | else |
| 1535 | { |
| 1536 | png_bytep sp, dp; |
| 1537 | png_byte save[2]; |
| 1538 | png_uint_32 i; |
| 1539 | |
| 1540 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1541 | i < row_info->width; i++) |
| 1542 | { |
| 1543 | save[0] = *(--sp); |
| 1544 | save[1] = *(--sp); |
| 1545 | *(--dp) = *(--sp); |
| 1546 | *(--dp) = *(--sp); |
| 1547 | *(--dp) = save[0]; |
| 1548 | *(--dp) = save[1]; |
| 1549 | } |
| 1550 | } |
| 1551 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1552 | } |
| 1553 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1554 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1555 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1556 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) |
| 1557 | void |
| 1558 | png_do_read_invert_alpha(png_row_infop row_info, png_bytep row) |
| 1559 | { |
| 1560 | png_debug(1, "in png_do_read_invert_alpha\n"); |
| 1561 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1562 | if (row != NULL && row_info != NULL) |
| 1563 | #endif |
| 1564 | { |
| 1565 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| 1566 | { |
| 1567 | /* This inverts the alpha channel in RGBA */ |
| 1568 | if (row_info->bit_depth == 8) |
| 1569 | { |
| 1570 | png_bytep sp, dp; |
| 1571 | png_uint_32 i; |
| 1572 | |
| 1573 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1574 | i < row_info->width; i++) |
| 1575 | { |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1576 | *(--dp) = 255 - *(--sp); |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1577 | *(--dp) = *(--sp); |
| 1578 | *(--dp) = *(--sp); |
| 1579 | *(--dp) = *(--sp); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1580 | } |
| 1581 | } |
| 1582 | /* This inverts the alpha channel in RRGGBBAA */ |
| 1583 | else |
| 1584 | { |
| 1585 | png_bytep sp, dp; |
| 1586 | png_uint_32 i; |
| 1587 | |
| 1588 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1589 | i < row_info->width; i++) |
| 1590 | { |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1591 | *(--dp) = 255 - *(--sp); |
| 1592 | *(--dp) = 255 - *(--sp); |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1593 | *(--dp) = *(--sp); |
| 1594 | *(--dp) = *(--sp); |
| 1595 | *(--dp) = *(--sp); |
| 1596 | *(--dp) = *(--sp); |
| 1597 | *(--dp) = *(--sp); |
| 1598 | *(--dp) = *(--sp); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1599 | } |
| 1600 | } |
| 1601 | } |
| 1602 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
| 1603 | { |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1604 | /* This inverts the alpha channel in GA */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1605 | if (row_info->bit_depth == 8) |
| 1606 | { |
| 1607 | png_bytep sp, dp; |
| 1608 | png_uint_32 i; |
| 1609 | |
| 1610 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1611 | i < row_info->width; i++) |
| 1612 | { |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1613 | *(--dp) = 255 - *(--sp); |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1614 | *(--dp) = *(--sp); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1615 | } |
| 1616 | } |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1617 | /* This inverts the alpha channel in GGAA */ |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1618 | else |
| 1619 | { |
| 1620 | png_bytep sp, dp; |
| 1621 | png_uint_32 i; |
| 1622 | |
| 1623 | for (i = 0, sp = dp = row + row_info->rowbytes; |
| 1624 | i < row_info->width; i++) |
| 1625 | { |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1626 | *(--dp) = 255 - *(--sp); |
| 1627 | *(--dp) = 255 - *(--sp); |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1628 | *(--dp) = *(--sp); |
| 1629 | *(--dp) = *(--sp); |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1630 | } |
| 1631 | } |
| 1632 | } |
| 1633 | } |
| 1634 | } |
| 1635 | #endif |
| 1636 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1637 | #if defined(PNG_READ_FILLER_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1638 | /* Add filler channel if we have RGB color */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1639 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1640 | png_do_read_filler(png_row_infop row_info, png_bytep row, |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1641 | png_uint_32 filler, png_uint_32 flags) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1642 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1643 | png_bytep sp, dp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1644 | png_uint_32 i; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1645 | |
| 1646 | png_debug(1, "in png_do_read_filler\n"); |
| 1647 | if ( |
| 1648 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1649 | row != NULL && row_info != NULL && |
| 1650 | #endif |
| 1651 | row_info->color_type == PNG_COLOR_TYPE_RGB && row_info->bit_depth == 8) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1652 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1653 | /* This changes the data from RGB to RGBX */ |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1654 | if (flags & PNG_FLAG_FILLER_AFTER) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1655 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1656 | for (i = 1, sp = row + (png_size_t)row_info->width * 3, |
| 1657 | dp = row + (png_size_t)row_info->width * 4; |
| 1658 | i < row_info->width; |
| 1659 | i++) |
| 1660 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1661 | *(--dp) = (png_byte)filler; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1662 | *(--dp) = *(--sp); |
| 1663 | *(--dp) = *(--sp); |
| 1664 | *(--dp) = *(--sp); |
| 1665 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1666 | *(--dp) = (png_byte)filler; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1667 | row_info->channels = 4; |
| 1668 | row_info->pixel_depth = 32; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1669 | row_info->rowbytes = row_info->width * 4; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1670 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1671 | /* This changes the data from RGB to XRGB */ |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1672 | else |
| 1673 | { |
| 1674 | for (i = 0, sp = row + (png_size_t)row_info->width * 3, |
| 1675 | dp = row + (png_size_t)row_info->width * 4; |
| 1676 | i < row_info->width; |
| 1677 | i++) |
| 1678 | { |
| 1679 | *(--dp) = *(--sp); |
| 1680 | *(--dp) = *(--sp); |
| 1681 | *(--dp) = *(--sp); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1682 | *(--dp) = (png_byte)filler; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1683 | } |
| 1684 | row_info->channels = 4; |
| 1685 | row_info->pixel_depth = 32; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1686 | row_info->rowbytes = row_info->width * 4; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1687 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1688 | } |
| 1689 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1690 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1691 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1692 | #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1693 | /* expand grayscale files to RGB, with or without alpha */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1694 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1695 | png_do_gray_to_rgb(png_row_infop row_info, png_bytep row) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1696 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1697 | png_bytep sp, dp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1698 | png_uint_32 i; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1699 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1700 | png_debug(1, "in png_do_gray_to_rgb\n"); |
| 1701 | if (row_info->bit_depth >= 8 && |
| 1702 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 1703 | row != NULL && row_info != NULL && |
| 1704 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1705 | !(row_info->color_type & PNG_COLOR_MASK_COLOR)) |
| 1706 | { |
| 1707 | if (row_info->color_type == PNG_COLOR_TYPE_GRAY) |
| 1708 | { |
| 1709 | if (row_info->bit_depth == 8) |
| 1710 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1711 | for (i = 0, sp = row + (png_size_t)row_info->width - 1, |
| 1712 | dp = row + (png_size_t)row_info->width * 3 - 1; |
| 1713 | i < row_info->width; |
| 1714 | i++) |
| 1715 | { |
| 1716 | *(dp--) = *sp; |
| 1717 | *(dp--) = *sp; |
| 1718 | *(dp--) = *sp; |
| 1719 | sp--; |
| 1720 | } |
| 1721 | } |
| 1722 | else |
| 1723 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1724 | for (i = 0, sp = row + (png_size_t)row_info->width * 2 - 1, |
| 1725 | dp = row + (png_size_t)row_info->width * 6 - 1; |
| 1726 | i < row_info->width; |
| 1727 | i++) |
| 1728 | { |
| 1729 | *(dp--) = *sp; |
| 1730 | *(dp--) = *(sp - 1); |
| 1731 | *(dp--) = *sp; |
| 1732 | *(dp--) = *(sp - 1); |
| 1733 | *(dp--) = *sp; |
| 1734 | *(dp--) = *(sp - 1); |
| 1735 | sp--; |
| 1736 | sp--; |
| 1737 | } |
| 1738 | } |
| 1739 | } |
| 1740 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
| 1741 | { |
| 1742 | if (row_info->bit_depth == 8) |
| 1743 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1744 | for (i = 0, sp = row + (png_size_t)row_info->width * 2 - 1, |
| 1745 | dp = row + (png_size_t)row_info->width * 4 - 1; |
| 1746 | i < row_info->width; |
| 1747 | i++) |
| 1748 | { |
| 1749 | *(dp--) = *(sp--); |
| 1750 | *(dp--) = *sp; |
| 1751 | *(dp--) = *sp; |
| 1752 | *(dp--) = *sp; |
| 1753 | sp--; |
| 1754 | } |
| 1755 | } |
| 1756 | else |
| 1757 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1758 | for (i = 0, sp = row + (png_size_t)row_info->width * 4 - 1, |
| 1759 | dp = row + (png_size_t)row_info->width * 8 - 1; |
| 1760 | i < row_info->width; |
| 1761 | i++) |
| 1762 | { |
| 1763 | *(dp--) = *(sp--); |
| 1764 | *(dp--) = *(sp--); |
| 1765 | *(dp--) = *sp; |
| 1766 | *(dp--) = *(sp - 1); |
| 1767 | *(dp--) = *sp; |
| 1768 | *(dp--) = *(sp - 1); |
| 1769 | *(dp--) = *sp; |
| 1770 | *(dp--) = *(sp - 1); |
| 1771 | sp--; |
| 1772 | sp--; |
| 1773 | } |
| 1774 | } |
| 1775 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1776 | row_info->channels += (png_byte)2; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1777 | row_info->color_type |= PNG_COLOR_MASK_COLOR; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1778 | row_info->pixel_depth = (png_byte)(row_info->channels * |
| 1779 | row_info->bit_depth); |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 1780 | row_info->rowbytes = ((row_info->width * |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1781 | row_info->pixel_depth + 7) >> 3); |
| 1782 | } |
| 1783 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 1784 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1785 | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 1786 | /* Build a grayscale palette. Palette is assumed to be 1 << bit_depth |
| 1787 | * large of png_color. This lets grayscale images be treated as |
| 1788 | * paletted. Most useful for gamma correction and simplification |
| 1789 | * of code. |
| 1790 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1791 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1792 | png_build_grayscale_palette(int bit_depth, png_colorp palette) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1793 | { |
| 1794 | int num_palette; |
| 1795 | int color_inc; |
| 1796 | int i; |
| 1797 | int v; |
| 1798 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1799 | png_debug(1, "in png_do_build_grayscale_palette\n"); |
| 1800 | if (palette == NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1801 | return; |
| 1802 | |
| 1803 | switch (bit_depth) |
| 1804 | { |
| 1805 | case 1: |
| 1806 | num_palette = 2; |
| 1807 | color_inc = 0xff; |
| 1808 | break; |
| 1809 | case 2: |
| 1810 | num_palette = 4; |
| 1811 | color_inc = 0x55; |
| 1812 | break; |
| 1813 | case 4: |
| 1814 | num_palette = 16; |
| 1815 | color_inc = 0x11; |
| 1816 | break; |
| 1817 | case 8: |
| 1818 | num_palette = 256; |
| 1819 | color_inc = 1; |
| 1820 | break; |
| 1821 | default: |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1822 | num_palette = 0; |
Guy Schalnat | 69b1448 | 1996-01-10 02:56:49 -0600 | [diff] [blame] | 1823 | color_inc = 0; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1824 | break; |
| 1825 | } |
| 1826 | |
| 1827 | for (i = 0, v = 0; i < num_palette; i++, v += color_inc) |
| 1828 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 1829 | palette[i].red = (png_byte)v; |
| 1830 | palette[i].green = (png_byte)v; |
| 1831 | palette[i].blue = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1832 | } |
| 1833 | } |
| 1834 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 1835 | /* This function is currently unused. Do we really need it? */ |
| 1836 | #if defined(PNG_READ_DITHER_SUPPORTED) && defined(PNG_CORRECT_PALETTE_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1837 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 1838 | png_correct_palette(png_structp png_ptr, png_colorp palette, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1839 | int num_palette) |
| 1840 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1841 | png_debug(1, "in png_correct_palette\n"); |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1842 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1843 | if ((png_ptr->transformations & (PNG_GAMMA)) && |
| 1844 | (png_ptr->transformations & (PNG_BACKGROUND))) |
| 1845 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1846 | png_color back, back_1; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1847 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1848 | if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_FILE) |
| 1849 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1850 | back.red = png_ptr->gamma_table[png_ptr->background.red]; |
| 1851 | back.green = png_ptr->gamma_table[png_ptr->background.green]; |
| 1852 | back.blue = png_ptr->gamma_table[png_ptr->background.blue]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1853 | |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1854 | back_1.red = png_ptr->gamma_to_1[png_ptr->background.red]; |
| 1855 | back_1.green = png_ptr->gamma_to_1[png_ptr->background.green]; |
| 1856 | back_1.blue = png_ptr->gamma_to_1[png_ptr->background.blue]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1857 | } |
| 1858 | else |
| 1859 | { |
| 1860 | double g; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1861 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 1862 | g = 1.0 / (png_ptr->background_gamma * png_ptr->screen_gamma); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1863 | |
| 1864 | if (png_ptr->background_gamma_type == PNG_BACKGROUND_GAMMA_SCREEN || |
| 1865 | fabs(g - 1.0) < PNG_GAMMA_THRESHOLD) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1866 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1867 | back.red = png_ptr->background.red; |
| 1868 | back.green = png_ptr->background.green; |
| 1869 | back.blue = png_ptr->background.blue; |
| 1870 | } |
| 1871 | else |
| 1872 | { |
| 1873 | back.red = |
| 1874 | (png_byte)(pow((double)png_ptr->background.red/255, g) * |
| 1875 | 255.0 + 0.5); |
| 1876 | back.green = |
| 1877 | (png_byte)(pow((double)png_ptr->background.green/255, g) * |
| 1878 | 255.0 + 0.5); |
| 1879 | back.blue = |
| 1880 | (png_byte)(pow((double)png_ptr->background.blue/255, g) * |
| 1881 | 255.0 + 0.5); |
| 1882 | } |
| 1883 | |
| 1884 | g = 1.0 / png_ptr->background_gamma; |
| 1885 | |
| 1886 | back_1.red = |
| 1887 | (png_byte)(pow((double)png_ptr->background.red/255, g) * |
| 1888 | 255.0 + 0.5); |
| 1889 | back_1.green = |
| 1890 | (png_byte)(pow((double)png_ptr->background.green/255, g) * |
| 1891 | 255.0 + 0.5); |
| 1892 | back_1.blue = |
| 1893 | (png_byte)(pow((double)png_ptr->background.blue/255, g) * |
| 1894 | 255.0 + 0.5); |
| 1895 | } |
| 1896 | |
| 1897 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
| 1898 | { |
| 1899 | png_uint_32 i; |
| 1900 | |
| 1901 | for (i = 0; i < (png_uint_32)num_palette; i++) |
| 1902 | { |
| 1903 | if (i < png_ptr->num_trans && png_ptr->trans[i] == 0) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1904 | { |
| 1905 | palette[i] = back; |
| 1906 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1907 | else if (i < png_ptr->num_trans && png_ptr->trans[i] != 0xff) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1908 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1909 | png_byte v, w; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1910 | |
| 1911 | v = png_ptr->gamma_to_1[png_ptr->palette[i].red]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1912 | png_composite(w, v, png_ptr->trans[i], back_1.red); |
| 1913 | palette[i].red = png_ptr->gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1914 | |
| 1915 | v = png_ptr->gamma_to_1[png_ptr->palette[i].green]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1916 | png_composite(w, v, png_ptr->trans[i], back_1.green); |
| 1917 | palette[i].green = png_ptr->gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1918 | |
| 1919 | v = png_ptr->gamma_to_1[png_ptr->palette[i].blue]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1920 | png_composite(w, v, png_ptr->trans[i], back_1.blue); |
| 1921 | palette[i].blue = png_ptr->gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1922 | } |
| 1923 | else |
| 1924 | { |
| 1925 | palette[i].red = png_ptr->gamma_table[palette[i].red]; |
| 1926 | palette[i].green = png_ptr->gamma_table[palette[i].green]; |
| 1927 | palette[i].blue = png_ptr->gamma_table[palette[i].blue]; |
| 1928 | } |
| 1929 | } |
| 1930 | } |
| 1931 | else |
| 1932 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1933 | int i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1934 | |
| 1935 | for (i = 0; i < num_palette; i++) |
| 1936 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1937 | if (palette[i].red == (png_byte)png_ptr->trans_values.gray) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1938 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1939 | palette[i] = back; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1940 | } |
| 1941 | else |
| 1942 | { |
| 1943 | palette[i].red = png_ptr->gamma_table[palette[i].red]; |
| 1944 | palette[i].green = png_ptr->gamma_table[palette[i].green]; |
| 1945 | palette[i].blue = png_ptr->gamma_table[palette[i].blue]; |
| 1946 | } |
| 1947 | } |
| 1948 | } |
| 1949 | } |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1950 | else |
| 1951 | #endif |
| 1952 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1953 | if (png_ptr->transformations & PNG_GAMMA) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1954 | { |
| 1955 | int i; |
| 1956 | |
| 1957 | for (i = 0; i < num_palette; i++) |
| 1958 | { |
| 1959 | palette[i].red = png_ptr->gamma_table[palette[i].red]; |
| 1960 | palette[i].green = png_ptr->gamma_table[palette[i].green]; |
| 1961 | palette[i].blue = png_ptr->gamma_table[palette[i].blue]; |
| 1962 | } |
| 1963 | } |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1964 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
| 1965 | else |
| 1966 | #endif |
| 1967 | #endif |
| 1968 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1969 | if (png_ptr->transformations & PNG_BACKGROUND) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1970 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1971 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1972 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1973 | png_color back; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1974 | |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1975 | back.red = (png_byte)png_ptr->background.red; |
| 1976 | back.green = (png_byte)png_ptr->background.green; |
| 1977 | back.blue = (png_byte)png_ptr->background.blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1978 | |
Glenn Randers-Pehrson | cbe52d8 | 1998-02-28 07:00:24 -0600 | [diff] [blame] | 1979 | for (i = 0; i < (int)png_ptr->num_trans; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1980 | { |
Glenn Randers-Pehrson | a357b99 | 1998-02-08 20:56:40 -0600 | [diff] [blame] | 1981 | if (png_ptr->trans[i] == 0) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1982 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 1983 | palette[i].red = back.red; |
| 1984 | palette[i].green = back.green; |
| 1985 | palette[i].blue = back.blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1986 | } |
Glenn Randers-Pehrson | a357b99 | 1998-02-08 20:56:40 -0600 | [diff] [blame] | 1987 | else if (png_ptr->trans[i] != 0xff) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1988 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 1989 | png_composite(palette[i].red, png_ptr->palette[i].red, |
| 1990 | png_ptr->trans[i], back.red); |
| 1991 | png_composite(palette[i].green, png_ptr->palette[i].green, |
| 1992 | png_ptr->trans[i], back.green); |
| 1993 | png_composite(palette[i].blue, png_ptr->palette[i].blue, |
| 1994 | png_ptr->trans[i], back.blue); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 1995 | } |
| 1996 | } |
| 1997 | } |
| 1998 | else /* assume grayscale palette (what else could it be?) */ |
| 1999 | { |
| 2000 | int i; |
| 2001 | |
| 2002 | for (i = 0; i < num_palette; i++) |
| 2003 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2004 | if (i == (png_byte)png_ptr->trans_values.gray) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2005 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 2006 | palette[i].red = (png_byte)png_ptr->background.red; |
| 2007 | palette[i].green = (png_byte)png_ptr->background.green; |
| 2008 | palette[i].blue = (png_byte)png_ptr->background.blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2009 | } |
| 2010 | } |
| 2011 | } |
| 2012 | } |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 2013 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2014 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2015 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2016 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2017 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2018 | /* Replace any alpha or transparency with the supplied background color. |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 2019 | * "background" is already in the screen gamma, while "background_1" is |
| 2020 | * at a gamma of 1.0. Paletted files have already been taken care of. |
| 2021 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2022 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2023 | png_do_background(png_row_infop row_info, png_bytep row, |
| 2024 | png_color_16p trans_values, png_color_16p background, |
| 2025 | png_color_16p background_1, |
| 2026 | png_bytep gamma_table, png_bytep gamma_from_1, png_bytep gamma_to_1, |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2027 | png_uint_16pp gamma_16, png_uint_16pp gamma_16_from_1, |
| 2028 | png_uint_16pp gamma_16_to_1, int gamma_shift) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2029 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2030 | png_bytep sp, dp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2031 | png_uint_32 i; |
| 2032 | int shift; |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 2033 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2034 | png_debug(1, "in png_do_background\n"); |
| 2035 | if (background != NULL && |
| 2036 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 2037 | row != NULL && row_info != NULL && |
| 2038 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2039 | (!(row_info->color_type & PNG_COLOR_MASK_ALPHA) || |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2040 | (row_info->color_type != PNG_COLOR_TYPE_PALETTE && trans_values))) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2041 | { |
| 2042 | switch (row_info->color_type) |
| 2043 | { |
| 2044 | case PNG_COLOR_TYPE_GRAY: |
| 2045 | { |
| 2046 | switch (row_info->bit_depth) |
| 2047 | { |
| 2048 | case 1: |
| 2049 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2050 | sp = row; |
| 2051 | shift = 7; |
| 2052 | for (i = 0; i < row_info->width; i++) |
| 2053 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2054 | if ((png_uint_16)((*sp >> shift) & 0x1) |
| 2055 | == trans_values->gray) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2056 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2057 | *sp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff); |
| 2058 | *sp |= (png_byte)(background->gray << shift); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2059 | } |
| 2060 | if (!shift) |
| 2061 | { |
| 2062 | shift = 7; |
| 2063 | sp++; |
| 2064 | } |
| 2065 | else |
| 2066 | shift--; |
| 2067 | } |
| 2068 | break; |
| 2069 | } |
| 2070 | case 2: |
| 2071 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2072 | sp = row; |
| 2073 | shift = 6; |
| 2074 | for (i = 0; i < row_info->width; i++) |
| 2075 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2076 | if ((png_uint_16)((*sp >> shift) & 0x3) |
| 2077 | == trans_values->gray) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2078 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2079 | *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); |
| 2080 | *sp |= (png_byte)(background->gray << shift); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2081 | } |
| 2082 | if (!shift) |
| 2083 | { |
| 2084 | shift = 6; |
| 2085 | sp++; |
| 2086 | } |
| 2087 | else |
| 2088 | shift -= 2; |
| 2089 | } |
| 2090 | break; |
| 2091 | } |
| 2092 | case 4: |
| 2093 | { |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 2094 | sp = row; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2095 | shift = 4; |
| 2096 | for (i = 0; i < row_info->width; i++) |
| 2097 | { |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2098 | if ((png_uint_16)((*sp >> shift) & 0xf) |
| 2099 | == trans_values->gray) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2100 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2101 | *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); |
| 2102 | *sp |= (png_byte)(background->gray << shift); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2103 | } |
| 2104 | if (!shift) |
| 2105 | { |
| 2106 | shift = 4; |
| 2107 | sp++; |
| 2108 | } |
| 2109 | else |
| 2110 | shift -= 4; |
| 2111 | } |
| 2112 | break; |
| 2113 | } |
| 2114 | case 8: |
| 2115 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2116 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2117 | if (gamma_table != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2118 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2119 | for (i = 0, sp = row; i < row_info->width; i++, sp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2120 | { |
| 2121 | if (*sp == trans_values->gray) |
| 2122 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2123 | *sp = (png_byte)background->gray; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2124 | } |
| 2125 | else |
| 2126 | { |
| 2127 | *sp = gamma_table[*sp]; |
| 2128 | } |
| 2129 | } |
| 2130 | } |
| 2131 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2132 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2133 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2134 | for (i = 0, sp = row; i < row_info->width; i++, sp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2135 | { |
| 2136 | if (*sp == trans_values->gray) |
| 2137 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2138 | *sp = (png_byte)background->gray; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2139 | } |
| 2140 | } |
| 2141 | } |
| 2142 | break; |
| 2143 | } |
| 2144 | case 16: |
| 2145 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2146 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2147 | if (gamma_16 != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2148 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2149 | for (i = 0, sp = row; i < row_info->width; i++, sp += 2) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2150 | { |
| 2151 | png_uint_16 v; |
| 2152 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2153 | v = ((png_uint_16)(*sp) << 8) + *(sp + 1); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2154 | if (v == trans_values->gray) |
| 2155 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2156 | /* background is already in screen gamma */ |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2157 | *sp = (png_byte)((background->gray >> 8) & 0xff); |
| 2158 | *(sp + 1) = (png_byte)(background->gray & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2159 | } |
| 2160 | else |
| 2161 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2162 | v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2163 | *sp = (png_byte)((v >> 8) & 0xff); |
Guy Schalnat | 4ee97b0 | 1996-01-16 01:51:56 -0600 | [diff] [blame] | 2164 | *(sp + 1) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2165 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2166 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2167 | } |
| 2168 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2169 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2170 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2171 | for (i = 0, sp = row; i < row_info->width; i++, sp += 2) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2172 | { |
| 2173 | png_uint_16 v; |
| 2174 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2175 | v = ((png_uint_16)(*sp) << 8) + *(sp + 1); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2176 | if (v == trans_values->gray) |
| 2177 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2178 | *sp = (png_byte)((background->gray >> 8) & 0xff); |
| 2179 | *(sp + 1) = (png_byte)(background->gray & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2180 | } |
| 2181 | } |
| 2182 | } |
| 2183 | break; |
| 2184 | } |
| 2185 | } |
| 2186 | break; |
| 2187 | } |
| 2188 | case PNG_COLOR_TYPE_RGB: |
| 2189 | { |
| 2190 | if (row_info->bit_depth == 8) |
| 2191 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2192 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2193 | if (gamma_table != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2194 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2195 | for (i = 0, sp = row; i < row_info->width; i++, sp += 3) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2196 | { |
| 2197 | if (*sp == trans_values->red && |
| 2198 | *(sp + 1) == trans_values->green && |
| 2199 | *(sp + 2) == trans_values->blue) |
| 2200 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2201 | *sp = (png_byte)background->red; |
| 2202 | *(sp + 1) = (png_byte)background->green; |
| 2203 | *(sp + 2) = (png_byte)background->blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2204 | } |
| 2205 | else |
| 2206 | { |
| 2207 | *sp = gamma_table[*sp]; |
| 2208 | *(sp + 1) = gamma_table[*(sp + 1)]; |
| 2209 | *(sp + 2) = gamma_table[*(sp + 2)]; |
| 2210 | } |
| 2211 | } |
| 2212 | } |
| 2213 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2214 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2215 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2216 | for (i = 0, sp = row; i < row_info->width; i++, sp += 3) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2217 | { |
| 2218 | if (*sp == trans_values->red && |
| 2219 | *(sp + 1) == trans_values->green && |
| 2220 | *(sp + 2) == trans_values->blue) |
| 2221 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2222 | *sp = (png_byte)background->red; |
| 2223 | *(sp + 1) = (png_byte)background->green; |
| 2224 | *(sp + 2) = (png_byte)background->blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2225 | } |
| 2226 | } |
| 2227 | } |
| 2228 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2229 | else /* if (row_info->bit_depth == 16) */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2230 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2231 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2232 | if (gamma_16 != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2233 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2234 | for (i = 0, sp = row; i < row_info->width; i++, sp += 6) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2235 | { |
| 2236 | png_uint_16 r, g, b; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2237 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2238 | r = ((png_uint_16)(*sp) << 8) + *(sp + 1); |
| 2239 | g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); |
| 2240 | b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5); |
| 2241 | if (r == trans_values->red && g == trans_values->green && |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2242 | b == trans_values->blue) |
| 2243 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2244 | /* background is already in screen gamma */ |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2245 | *sp = (png_byte)((background->red >> 8) & 0xff); |
| 2246 | *(sp + 1) = (png_byte)(background->red & 0xff); |
| 2247 | *(sp + 2) = (png_byte)((background->green >> 8) & 0xff); |
| 2248 | *(sp + 3) = (png_byte)(background->green & 0xff); |
| 2249 | *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff); |
| 2250 | *(sp + 5) = (png_byte)(background->blue & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2251 | } |
| 2252 | else |
| 2253 | { |
| 2254 | png_uint_16 v; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2255 | v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2256 | *sp = (png_byte)((v >> 8) & 0xff); |
Guy Schalnat | 4ee97b0 | 1996-01-16 01:51:56 -0600 | [diff] [blame] | 2257 | *(sp + 1) = (png_byte)(v & 0xff); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2258 | v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2259 | *(sp + 2) = (png_byte)((v >> 8) & 0xff); |
| 2260 | *(sp + 3) = (png_byte)(v & 0xff); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2261 | v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2262 | *(sp + 4) = (png_byte)((v >> 8) & 0xff); |
| 2263 | *(sp + 5) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2264 | } |
| 2265 | } |
| 2266 | } |
| 2267 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2268 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2269 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2270 | for (i = 0, sp = row; i < row_info->width; i++, sp += 6) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2271 | { |
| 2272 | png_uint_16 r, g, b; |
| 2273 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2274 | r = ((png_uint_16)(*sp) << 8) + *(sp + 1); |
| 2275 | g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); |
| 2276 | b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5); |
| 2277 | if (r == trans_values->red && g == trans_values->green && |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2278 | b == trans_values->blue) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2279 | { |
| 2280 | *sp = (png_byte)((background->red >> 8) & 0xff); |
| 2281 | *(sp + 1) = (png_byte)(background->red & 0xff); |
| 2282 | *(sp + 2) = (png_byte)((background->green >> 8) & 0xff); |
| 2283 | *(sp + 3) = (png_byte)(background->green & 0xff); |
| 2284 | *(sp + 4) = (png_byte)((background->blue >> 8) & 0xff); |
| 2285 | *(sp + 5) = (png_byte)(background->blue & 0xff); |
| 2286 | } |
| 2287 | } |
| 2288 | } |
| 2289 | } |
| 2290 | break; |
| 2291 | } |
| 2292 | case PNG_COLOR_TYPE_GRAY_ALPHA: |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2293 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2294 | if (row_info->bit_depth == 8) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2295 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2296 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2297 | if (gamma_to_1 != NULL && gamma_from_1 != NULL && |
| 2298 | gamma_table != NULL) |
| 2299 | { |
| 2300 | for (i = 0, sp = row, dp = row; |
| 2301 | i < row_info->width; i++, sp += 2, dp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2302 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2303 | png_uint_16 a; |
| 2304 | |
| 2305 | a = *(sp + 1); |
| 2306 | if (a == 0xff) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2307 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2308 | *dp = gamma_table[*sp]; |
| 2309 | } |
| 2310 | else if (a == 0) |
| 2311 | { |
| 2312 | /* background is already in screen gamma */ |
| 2313 | *dp = (png_byte)background->gray; |
| 2314 | } |
| 2315 | else |
| 2316 | { |
| 2317 | png_byte v, w; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2318 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2319 | v = gamma_to_1[*sp]; |
| 2320 | png_composite(w, v, a, background_1->gray); |
| 2321 | *dp = gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2322 | } |
| 2323 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2324 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2325 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2326 | #endif |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2327 | { |
| 2328 | for (i = 0, sp = row, dp = row; |
| 2329 | i < row_info->width; i++, sp += 2, dp++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2330 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2331 | png_byte a; |
| 2332 | |
| 2333 | a = *(sp + 1); |
| 2334 | if (a == 0xff) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2335 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2336 | *dp = *sp; |
| 2337 | } |
| 2338 | else if (a == 0) |
| 2339 | { |
| 2340 | *dp = (png_byte)background->gray; |
| 2341 | } |
| 2342 | else |
| 2343 | { |
| 2344 | png_composite(*dp, *sp, a, background_1->gray); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2345 | } |
| 2346 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2347 | } |
| 2348 | } |
| 2349 | else /* if (png_ptr->bit_depth == 16) */ |
| 2350 | { |
| 2351 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
| 2352 | if (gamma_16 != NULL && gamma_16_from_1 != NULL && |
| 2353 | gamma_16_to_1 != NULL) |
| 2354 | { |
| 2355 | for (i = 0, sp = row, dp = row; |
| 2356 | i < row_info->width; i++, sp += 4, dp += 2) |
| 2357 | { |
| 2358 | png_uint_16 a; |
| 2359 | |
| 2360 | a = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); |
| 2361 | if (a == (png_uint_16)0xffff) |
| 2362 | { |
| 2363 | png_uint_16 v; |
| 2364 | |
| 2365 | v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; |
| 2366 | *dp = (png_byte)((v >> 8) & 0xff); |
| 2367 | *(dp + 1) = (png_byte)(v & 0xff); |
| 2368 | } |
| 2369 | else if (a == 0) |
| 2370 | { |
| 2371 | /* background is already in screen gamma */ |
| 2372 | *dp = (png_byte)((background->gray >> 8) & 0xff); |
| 2373 | *(dp + 1) = (png_byte)(background->gray & 0xff); |
| 2374 | } |
| 2375 | else |
| 2376 | { |
| 2377 | png_uint_16 g, v, w; |
| 2378 | |
| 2379 | g = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp]; |
| 2380 | png_composite_16(v, g, a, background_1->gray); |
| 2381 | w = gamma_16_from_1[(v&0xff) >> gamma_shift][v >> 8]; |
| 2382 | *dp = (png_byte)((w >> 8) & 0xff); |
| 2383 | *(dp + 1) = (png_byte)(w & 0xff); |
| 2384 | } |
| 2385 | } |
| 2386 | } |
| 2387 | else |
| 2388 | #endif |
| 2389 | { |
| 2390 | for (i = 0, sp = row, dp = row; |
| 2391 | i < row_info->width; i++, sp += 4, dp += 2) |
| 2392 | { |
| 2393 | png_uint_16 a; |
| 2394 | |
| 2395 | a = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); |
| 2396 | if (a == (png_uint_16)0xffff) |
| 2397 | { |
| 2398 | png_memcpy(dp, sp, 2); |
| 2399 | } |
| 2400 | else if (a == 0) |
| 2401 | { |
| 2402 | *dp = (png_byte)((background->gray >> 8) & 0xff); |
| 2403 | *(dp + 1) = (png_byte)(background->gray & 0xff); |
| 2404 | } |
| 2405 | else |
| 2406 | { |
| 2407 | png_uint_16 g, v; |
| 2408 | |
| 2409 | g = ((png_uint_16)(*sp) << 8) + *(sp + 1); |
| 2410 | png_composite_16(v, g, a, background_1->gray); |
| 2411 | *dp = (png_byte)((v >> 8) & 0xff); |
| 2412 | *(dp + 1) = (png_byte)(v & 0xff); |
| 2413 | } |
| 2414 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2415 | } |
| 2416 | } |
| 2417 | break; |
| 2418 | } |
| 2419 | case PNG_COLOR_TYPE_RGB_ALPHA: |
| 2420 | { |
| 2421 | if (row_info->bit_depth == 8) |
| 2422 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2423 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2424 | if (gamma_to_1 != NULL && gamma_from_1 != NULL && |
| 2425 | gamma_table != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2426 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2427 | for (i = 0, sp = row, dp = row; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2428 | i < row_info->width; i++, sp += 4, dp += 3) |
| 2429 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2430 | png_byte a; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2431 | |
| 2432 | a = *(sp + 3); |
| 2433 | if (a == 0xff) |
| 2434 | { |
| 2435 | *dp = gamma_table[*sp]; |
| 2436 | *(dp + 1) = gamma_table[*(sp + 1)]; |
| 2437 | *(dp + 2) = gamma_table[*(sp + 2)]; |
| 2438 | } |
| 2439 | else if (a == 0) |
| 2440 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2441 | /* background is already in screen gamma */ |
| 2442 | *dp = (png_byte)background->red; |
| 2443 | *(dp + 1) = (png_byte)background->green; |
| 2444 | *(dp + 2) = (png_byte)background->blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2445 | } |
| 2446 | else |
| 2447 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2448 | png_byte v, w; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2449 | |
| 2450 | v = gamma_to_1[*sp]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2451 | png_composite(w, v, a, background_1->red); |
| 2452 | *dp = gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2453 | v = gamma_to_1[*(sp + 1)]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2454 | png_composite(w, v, a, background_1->green); |
| 2455 | *(dp + 1) = gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2456 | v = gamma_to_1[*(sp + 2)]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2457 | png_composite(w, v, a, background_1->blue); |
| 2458 | *(dp + 2) = gamma_from_1[w]; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2459 | } |
| 2460 | } |
| 2461 | } |
| 2462 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2463 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2464 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2465 | for (i = 0, sp = row, dp = row; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2466 | i < row_info->width; i++, sp += 4, dp += 3) |
| 2467 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2468 | png_byte a; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2469 | |
| 2470 | a = *(sp + 3); |
| 2471 | if (a == 0xff) |
| 2472 | { |
| 2473 | *dp = *sp; |
| 2474 | *(dp + 1) = *(sp + 1); |
| 2475 | *(dp + 2) = *(sp + 2); |
| 2476 | } |
| 2477 | else if (a == 0) |
| 2478 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2479 | *dp = (png_byte)background->red; |
| 2480 | *(dp + 1) = (png_byte)background->green; |
| 2481 | *(dp + 2) = (png_byte)background->blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2482 | } |
| 2483 | else |
| 2484 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2485 | png_composite(*dp, *sp, a, background->red); |
| 2486 | png_composite(*(dp + 1), *(sp + 1), a, |
| 2487 | background->green); |
| 2488 | png_composite(*(dp + 2), *(sp + 2), a, |
| 2489 | background->blue); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2490 | } |
| 2491 | } |
| 2492 | } |
| 2493 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2494 | else /* if (row_info->bit_depth == 16) */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2495 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2496 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2497 | if (gamma_16 != NULL && gamma_16_from_1 != NULL && |
| 2498 | gamma_16_to_1 != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2499 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2500 | for (i = 0, sp = row, dp = row; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2501 | i < row_info->width; i++, sp += 8, dp += 6) |
| 2502 | { |
| 2503 | png_uint_16 a; |
| 2504 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2505 | a = (png_uint_16)(((png_uint_16)(*(sp + 6)) << 8) + |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2506 | (png_uint_16)(*(sp + 7))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2507 | if (a == (png_uint_16)0xffff) |
| 2508 | { |
| 2509 | png_uint_16 v; |
| 2510 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2511 | v = gamma_16[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2512 | *dp = (png_byte)((v >> 8) & 0xff); |
| 2513 | *(dp + 1) = (png_byte)(v & 0xff); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2514 | v = gamma_16[*(sp + 3) >> gamma_shift][*(sp + 2)]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2515 | *(dp + 2) = (png_byte)((v >> 8) & 0xff); |
| 2516 | *(dp + 3) = (png_byte)(v & 0xff); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2517 | v = gamma_16[*(sp + 5) >> gamma_shift][*(sp + 4)]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2518 | *(dp + 4) = (png_byte)((v >> 8) & 0xff); |
| 2519 | *(dp + 5) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2520 | } |
| 2521 | else if (a == 0) |
| 2522 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2523 | /* background is already in screen gamma */ |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2524 | *dp = (png_byte)((background->red >> 8) & 0xff); |
| 2525 | *(dp + 1) = (png_byte)(background->red & 0xff); |
| 2526 | *(dp + 2) = (png_byte)((background->green >> 8) & 0xff); |
| 2527 | *(dp + 3) = (png_byte)(background->green & 0xff); |
| 2528 | *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff); |
| 2529 | *(dp + 5) = (png_byte)(background->blue & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2530 | } |
| 2531 | else |
| 2532 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2533 | png_uint_16 v, w, x; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2534 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2535 | v = gamma_16_to_1[*(sp + 1) >> gamma_shift][*sp]; |
| 2536 | png_composite_16(w, v, a, background->red); |
| 2537 | x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8]; |
| 2538 | *dp = (png_byte)((x >> 8) & 0xff); |
| 2539 | *(dp + 1) = (png_byte)(x & 0xff); |
| 2540 | v = gamma_16_to_1[*(sp + 3) >> gamma_shift][*(sp + 2)]; |
| 2541 | png_composite_16(w, v, a, background->green); |
| 2542 | x = gamma_16_from_1[((w&0xff) >> gamma_shift)][w >> 8]; |
| 2543 | *(dp + 2) = (png_byte)((x >> 8) & 0xff); |
| 2544 | *(dp + 3) = (png_byte)(x & 0xff); |
| 2545 | v = gamma_16_to_1[*(sp + 5) >> gamma_shift][*(sp + 4)]; |
| 2546 | png_composite_16(w, v, a, background->blue); |
| 2547 | x = gamma_16_from_1[(w & 0xff) >> gamma_shift][w >> 8]; |
| 2548 | *(dp + 4) = (png_byte)((x >> 8) & 0xff); |
| 2549 | *(dp + 5) = (png_byte)(x & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2550 | } |
| 2551 | } |
| 2552 | } |
| 2553 | else |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2554 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2555 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2556 | for (i = 0, sp = row, dp = row; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2557 | i < row_info->width; i++, sp += 8, dp += 6) |
| 2558 | { |
| 2559 | png_uint_16 a; |
| 2560 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2561 | a = (png_uint_16)(((png_uint_16)(*(sp + 6)) << 8) + |
| 2562 | (png_uint_16)(*(sp + 7))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2563 | if (a == (png_uint_16)0xffff) |
| 2564 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2565 | png_memcpy(dp, sp, 6); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2566 | } |
| 2567 | else if (a == 0) |
| 2568 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2569 | *dp = (png_byte)((background->red >> 8) & 0xff); |
| 2570 | *(dp + 1) = (png_byte)(background->red & 0xff); |
| 2571 | *(dp + 2) = (png_byte)((background->green >> 8) & 0xff); |
| 2572 | *(dp + 3) = (png_byte)(background->green & 0xff); |
| 2573 | *(dp + 4) = (png_byte)((background->blue >> 8) & 0xff); |
| 2574 | *(dp + 5) = (png_byte)(background->blue & 0xff); |
| 2575 | } |
| 2576 | else |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2577 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2578 | png_uint_16 r, g, b, v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2579 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2580 | r = ((png_uint_16)(*sp) << 8) + *(sp + 1); |
| 2581 | g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3); |
| 2582 | b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5); |
| 2583 | |
| 2584 | png_composite_16(v, r, a, background->red); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2585 | *dp = (png_byte)((v >> 8) & 0xff); |
| 2586 | *(dp + 1) = (png_byte)(v & 0xff); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2587 | png_composite_16(v, g, a, background->green); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2588 | *(dp + 2) = (png_byte)((v >> 8) & 0xff); |
| 2589 | *(dp + 3) = (png_byte)(v & 0xff); |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 2590 | png_composite_16(v, b, a, background->blue); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2591 | *(dp + 4) = (png_byte)((v >> 8) & 0xff); |
| 2592 | *(dp + 5) = (png_byte)(v & 0xff); |
| 2593 | } |
| 2594 | } |
| 2595 | } |
| 2596 | } |
| 2597 | break; |
| 2598 | } |
| 2599 | } |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 2600 | |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2601 | if (row_info->color_type & PNG_COLOR_MASK_ALPHA) |
| 2602 | { |
| 2603 | row_info->color_type &= ~PNG_COLOR_MASK_ALPHA; |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 2604 | row_info->channels--; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2605 | row_info->pixel_depth = (png_byte)(row_info->channels * |
| 2606 | row_info->bit_depth); |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2607 | row_info->rowbytes = ((row_info->width * |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2608 | row_info->pixel_depth + 7) >> 3); |
| 2609 | } |
| 2610 | } |
| 2611 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2612 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2613 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2614 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2615 | /* Gamma correct the image, avoiding the alpha channel. Make sure |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 2616 | * you do this after you deal with the trasparency issue on grayscale |
| 2617 | * or rgb images. If your bit depth is 8, use gamma_table, if it |
| 2618 | * is 16, use gamma_16_table and gamma_shift. Build these with |
| 2619 | * build_gamma_table(). |
| 2620 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2621 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2622 | png_do_gamma(png_row_infop row_info, png_bytep row, |
| 2623 | png_bytep gamma_table, png_uint_16pp gamma_16_table, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2624 | int gamma_shift) |
| 2625 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2626 | png_bytep sp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2627 | png_uint_32 i; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2628 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2629 | png_debug(1, "in png_do_gamma\n"); |
| 2630 | if ( |
| 2631 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 2632 | row != NULL && row_info != NULL && |
| 2633 | #endif |
| 2634 | ((row_info->bit_depth <= 8 && gamma_table != NULL) || |
| 2635 | (row_info->bit_depth == 16 && gamma_16_table != NULL))) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2636 | { |
| 2637 | switch (row_info->color_type) |
| 2638 | { |
| 2639 | case PNG_COLOR_TYPE_RGB: |
| 2640 | { |
| 2641 | if (row_info->bit_depth == 8) |
| 2642 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2643 | for (i = 0, sp = row; i < row_info->width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2644 | { |
| 2645 | *sp = gamma_table[*sp]; |
| 2646 | sp++; |
| 2647 | *sp = gamma_table[*sp]; |
| 2648 | sp++; |
| 2649 | *sp = gamma_table[*sp]; |
| 2650 | sp++; |
| 2651 | } |
| 2652 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2653 | else /* if (row_info->bit_depth == 16) */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2654 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2655 | for (i = 0, sp = row; i < row_info->width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2656 | { |
| 2657 | png_uint_16 v; |
| 2658 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2659 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2660 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2661 | *(sp + 1) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2662 | sp += 2; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2663 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2664 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2665 | *(sp + 1) = (png_byte)(v & 0xff); |
| 2666 | sp += 2; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2667 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2668 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2669 | *(sp + 1) = (png_byte)(v & 0xff); |
| 2670 | sp += 2; |
| 2671 | } |
| 2672 | } |
| 2673 | break; |
| 2674 | } |
| 2675 | case PNG_COLOR_TYPE_RGB_ALPHA: |
| 2676 | { |
| 2677 | if (row_info->bit_depth == 8) |
| 2678 | { |
| 2679 | for (i = 0, sp = row; |
| 2680 | i < row_info->width; i++) |
| 2681 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2682 | *sp = gamma_table[*sp]; |
| 2683 | sp++; |
| 2684 | *sp = gamma_table[*sp]; |
| 2685 | sp++; |
| 2686 | *sp = gamma_table[*sp]; |
| 2687 | sp++; |
| 2688 | sp++; |
| 2689 | } |
| 2690 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2691 | else /* if (row_info->bit_depth == 16) */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2692 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2693 | for (i = 0, sp = row; |
| 2694 | i < row_info->width; i++) |
| 2695 | { |
| 2696 | png_uint_16 v; |
| 2697 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2698 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2699 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2700 | *(sp + 1) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2701 | sp += 2; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2702 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2703 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2704 | *(sp + 1) = (png_byte)(v & 0xff); |
| 2705 | sp += 2; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2706 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2707 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2708 | *(sp + 1) = (png_byte)(v & 0xff); |
| 2709 | sp += 4; |
| 2710 | } |
| 2711 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2712 | break; |
| 2713 | } |
| 2714 | case PNG_COLOR_TYPE_GRAY_ALPHA: |
| 2715 | { |
| 2716 | if (row_info->bit_depth == 8) |
| 2717 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2718 | for (i = 0, sp = row; |
| 2719 | i < row_info->width; i++) |
| 2720 | { |
| 2721 | *sp = gamma_table[*sp]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2722 | sp += 2; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2723 | } |
| 2724 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2725 | else /* if (row_info->bit_depth == 16) */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2726 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2727 | for (i = 0, sp = row; |
| 2728 | i < row_info->width; i++) |
| 2729 | { |
| 2730 | png_uint_16 v; |
| 2731 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2732 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2733 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2734 | *(sp + 1) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2735 | sp += 4; |
| 2736 | } |
| 2737 | } |
| 2738 | break; |
| 2739 | } |
| 2740 | case PNG_COLOR_TYPE_GRAY: |
| 2741 | { |
Glenn Randers-Pehrson | 2687fcc | 1998-01-07 20:54:20 -0600 | [diff] [blame] | 2742 | if (row_info->bit_depth == 2) |
| 2743 | { |
| 2744 | for (i = 0, sp = row; i < row_info->width; i += 4) |
| 2745 | { |
| 2746 | int a = *sp & 0xc0; |
| 2747 | int b = *sp & 0x30; |
| 2748 | int c = *sp & 0x0c; |
| 2749 | int d = *sp & 0x03; |
| 2750 | |
| 2751 | *sp = ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)]) ) & 0xc0)| |
| 2752 | ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)| |
| 2753 | ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)| |
| 2754 | ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ); |
| 2755 | sp++; |
| 2756 | } |
| 2757 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2758 | if (row_info->bit_depth == 4) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2759 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2760 | for (i = 0, sp = row; i < row_info->width; i += 2) |
| 2761 | { |
| 2762 | int msb = *sp & 0xf0; |
| 2763 | int lsb = *sp & 0x0f; |
| 2764 | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 2765 | *sp = (((int)gamma_table[msb | (msb >> 4)]) & 0xf0) | |
| 2766 | (((int)gamma_table[(lsb << 4) | lsb]) >> 4); |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2767 | sp++; |
| 2768 | } |
| 2769 | } |
| 2770 | else if (row_info->bit_depth == 8) |
| 2771 | { |
| 2772 | for (i = 0, sp = row; i < row_info->width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2773 | { |
| 2774 | *sp = gamma_table[*sp]; |
| 2775 | sp++; |
| 2776 | } |
| 2777 | } |
| 2778 | else if (row_info->bit_depth == 16) |
| 2779 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2780 | for (i = 0, sp = row; i < row_info->width; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2781 | { |
| 2782 | png_uint_16 v; |
| 2783 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2784 | v = gamma_16_table[*(sp + 1) >> gamma_shift][*sp]; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2785 | *sp = (png_byte)((v >> 8) & 0xff); |
| 2786 | *(sp + 1) = (png_byte)(v & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2787 | sp += 2; |
| 2788 | } |
| 2789 | } |
| 2790 | break; |
| 2791 | } |
| 2792 | } |
| 2793 | } |
| 2794 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2795 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2796 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2797 | #if defined(PNG_READ_EXPAND_SUPPORTED) |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 2798 | /* Expands a palette row to an rgb or rgba row depending |
| 2799 | * upon whether you supply trans and num_trans. |
| 2800 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2801 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2802 | png_do_expand_palette(png_row_infop row_info, png_bytep row, |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2803 | png_colorp palette, png_bytep trans, int num_trans) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2804 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2805 | int shift, value; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2806 | png_bytep sp, dp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2807 | png_uint_32 i; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2808 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2809 | png_debug(1, "in png_do_expand_palette\n"); |
| 2810 | if ( |
| 2811 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 2812 | row != NULL && row_info != NULL && |
| 2813 | #endif |
| 2814 | row_info->color_type == PNG_COLOR_TYPE_PALETTE) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2815 | { |
| 2816 | if (row_info->bit_depth < 8) |
| 2817 | { |
| 2818 | switch (row_info->bit_depth) |
| 2819 | { |
| 2820 | case 1: |
| 2821 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2822 | sp = row + (png_size_t)((row_info->width - 1) >> 3); |
| 2823 | dp = row + (png_size_t)row_info->width - 1; |
| 2824 | shift = 7 - (int)((row_info->width + 7) & 7); |
| 2825 | for (i = 0; i < row_info->width; i++) |
| 2826 | { |
| 2827 | if ((*sp >> shift) & 0x1) |
| 2828 | *dp = 1; |
| 2829 | else |
| 2830 | *dp = 0; |
| 2831 | if (shift == 7) |
| 2832 | { |
| 2833 | shift = 0; |
| 2834 | sp--; |
| 2835 | } |
| 2836 | else |
| 2837 | shift++; |
| 2838 | |
| 2839 | dp--; |
| 2840 | } |
| 2841 | break; |
| 2842 | } |
| 2843 | case 2: |
| 2844 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2845 | sp = row + (png_size_t)((row_info->width - 1) >> 2); |
| 2846 | dp = row + (png_size_t)row_info->width - 1; |
| 2847 | shift = (int)((3 - ((row_info->width + 3) & 3)) << 1); |
| 2848 | for (i = 0; i < row_info->width; i++) |
| 2849 | { |
| 2850 | value = (*sp >> shift) & 0x3; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2851 | *dp = (png_byte)value; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2852 | if (shift == 6) |
| 2853 | { |
| 2854 | shift = 0; |
| 2855 | sp--; |
| 2856 | } |
| 2857 | else |
| 2858 | shift += 2; |
| 2859 | |
| 2860 | dp--; |
| 2861 | } |
| 2862 | break; |
| 2863 | } |
| 2864 | case 4: |
| 2865 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2866 | sp = row + (png_size_t)((row_info->width - 1) >> 1); |
| 2867 | dp = row + (png_size_t)row_info->width - 1; |
| 2868 | shift = (int)((row_info->width & 1) << 2); |
| 2869 | for (i = 0; i < row_info->width; i++) |
| 2870 | { |
| 2871 | value = (*sp >> shift) & 0xf; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2872 | *dp = (png_byte)value; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2873 | if (shift == 4) |
| 2874 | { |
| 2875 | shift = 0; |
| 2876 | sp--; |
| 2877 | } |
| 2878 | else |
| 2879 | shift += 4; |
| 2880 | |
| 2881 | dp--; |
| 2882 | } |
| 2883 | break; |
| 2884 | } |
| 2885 | } |
| 2886 | row_info->bit_depth = 8; |
| 2887 | row_info->pixel_depth = 8; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2888 | row_info->rowbytes = row_info->width; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2889 | } |
| 2890 | switch (row_info->bit_depth) |
| 2891 | { |
| 2892 | case 8: |
| 2893 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2894 | if (trans != NULL) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2895 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2896 | sp = row + (png_size_t)row_info->width - 1; |
| 2897 | dp = row + (png_size_t)(row_info->width << 2) - 1; |
| 2898 | |
| 2899 | for (i = 0; i < row_info->width; i++) |
| 2900 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2901 | if ((int)(*sp) >= num_trans) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2902 | *dp-- = 0xff; |
| 2903 | else |
| 2904 | *dp-- = trans[*sp]; |
| 2905 | *dp-- = palette[*sp].blue; |
| 2906 | *dp-- = palette[*sp].green; |
| 2907 | *dp-- = palette[*sp].red; |
| 2908 | sp--; |
| 2909 | } |
| 2910 | row_info->bit_depth = 8; |
| 2911 | row_info->pixel_depth = 32; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2912 | row_info->rowbytes = row_info->width * 4; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2913 | row_info->color_type = 6; |
| 2914 | row_info->channels = 4; |
| 2915 | } |
| 2916 | else |
| 2917 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2918 | sp = row + (png_size_t)row_info->width - 1; |
| 2919 | dp = row + (png_size_t)(row_info->width * 3) - 1; |
| 2920 | |
| 2921 | for (i = 0; i < row_info->width; i++) |
| 2922 | { |
| 2923 | *dp-- = palette[*sp].blue; |
| 2924 | *dp-- = palette[*sp].green; |
| 2925 | *dp-- = palette[*sp].red; |
| 2926 | sp--; |
| 2927 | } |
| 2928 | row_info->bit_depth = 8; |
| 2929 | row_info->pixel_depth = 24; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 2930 | row_info->rowbytes = row_info->width * 3; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2931 | row_info->color_type = 2; |
| 2932 | row_info->channels = 3; |
| 2933 | } |
| 2934 | break; |
| 2935 | } |
| 2936 | } |
| 2937 | } |
| 2938 | } |
| 2939 | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 2940 | /* If the bit depth < 8, it is expanded to 8. Also, if the |
| 2941 | * transparency value is supplied, an alpha channel is built. |
| 2942 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2943 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2944 | png_do_expand(png_row_infop row_info, png_bytep row, |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 2945 | png_color_16p trans_value) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2946 | { |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2947 | int shift, value; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2948 | png_bytep sp, dp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 2949 | png_uint_32 i; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 2950 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2951 | png_debug(1, "in png_do_expand\n"); |
| 2952 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 2953 | if (row != NULL && row_info != NULL) |
| 2954 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2955 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 2956 | if (row_info->color_type == PNG_COLOR_TYPE_GRAY) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2957 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 2958 | png_uint_16 gray = trans_value ? trans_value->gray : 0; |
| 2959 | |
| 2960 | if (row_info->bit_depth < 8) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2961 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 2962 | switch (row_info->bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 2963 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 2964 | case 1: |
| 2965 | { |
| 2966 | gray *= 0xff; |
| 2967 | sp = row + (png_size_t)((row_info->width - 1) >> 3); |
| 2968 | dp = row + (png_size_t)row_info->width - 1; |
| 2969 | shift = 7 - (int)((row_info->width + 7) & 7); |
| 2970 | for (i = 0; i < row_info->width; i++) |
| 2971 | { |
| 2972 | if ((*sp >> shift) & 0x1) |
| 2973 | *dp = 0xff; |
| 2974 | else |
| 2975 | *dp = 0; |
| 2976 | if (shift == 7) |
| 2977 | { |
| 2978 | shift = 0; |
| 2979 | sp--; |
| 2980 | } |
| 2981 | else |
| 2982 | shift++; |
| 2983 | |
| 2984 | dp--; |
| 2985 | } |
| 2986 | break; |
| 2987 | } |
| 2988 | case 2: |
| 2989 | { |
| 2990 | gray *= 0x55; |
| 2991 | sp = row + (png_size_t)((row_info->width - 1) >> 2); |
| 2992 | dp = row + (png_size_t)row_info->width - 1; |
| 2993 | shift = (int)((3 - ((row_info->width + 3) & 3)) << 1); |
| 2994 | for (i = 0; i < row_info->width; i++) |
| 2995 | { |
| 2996 | value = (*sp >> shift) & 0x3; |
| 2997 | *dp = (png_byte)(value | (value << 2) | (value << 4) | |
| 2998 | (value << 6)); |
| 2999 | if (shift == 6) |
| 3000 | { |
| 3001 | shift = 0; |
| 3002 | sp--; |
| 3003 | } |
| 3004 | else |
| 3005 | shift += 2; |
| 3006 | |
| 3007 | dp--; |
| 3008 | } |
| 3009 | break; |
| 3010 | } |
| 3011 | case 4: |
| 3012 | { |
| 3013 | gray *= 0x11; |
| 3014 | sp = row + (png_size_t)((row_info->width - 1) >> 1); |
| 3015 | dp = row + (png_size_t)row_info->width - 1; |
| 3016 | shift = (int)((1 - ((row_info->width + 1) & 1)) << 2); |
| 3017 | for (i = 0; i < row_info->width; i++) |
| 3018 | { |
| 3019 | value = (*sp >> shift) & 0xf; |
| 3020 | *dp = (png_byte)(value | (value << 4)); |
| 3021 | if (shift == 4) |
| 3022 | { |
| 3023 | shift = 0; |
| 3024 | sp--; |
| 3025 | } |
| 3026 | else |
| 3027 | shift = 4; |
| 3028 | |
| 3029 | dp--; |
| 3030 | } |
| 3031 | break; |
| 3032 | } |
| 3033 | } |
| 3034 | row_info->bit_depth = 8; |
| 3035 | row_info->pixel_depth = 8; |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3036 | row_info->rowbytes = row_info->width; |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3037 | } |
| 3038 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3039 | if (trans_value != NULL) |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3040 | { |
| 3041 | if (row_info->bit_depth == 8) |
| 3042 | { |
| 3043 | sp = row + (png_size_t)row_info->width - 1; |
| 3044 | dp = row + (png_size_t)(row_info->width << 1) - 1; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3045 | for (i = 0; i < row_info->width; i++) |
| 3046 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3047 | if (*sp == gray) |
| 3048 | *dp-- = 0; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3049 | else |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3050 | *dp-- = 0xff; |
| 3051 | *dp-- = *sp--; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3052 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3053 | } |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3054 | else if (row_info->bit_depth == 16) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3055 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3056 | sp = row + row_info->rowbytes - 1; |
| 3057 | dp = row + (row_info->rowbytes << 1) - 1; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3058 | for (i = 0; i < row_info->width; i++) |
| 3059 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3060 | if (((png_uint_16)*(sp) | |
| 3061 | ((png_uint_16)*(sp - 1) << 8)) == gray) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3062 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3063 | *dp-- = 0; |
| 3064 | *dp-- = 0; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3065 | } |
| 3066 | else |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3067 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3068 | *dp-- = 0xff; |
| 3069 | *dp-- = 0xff; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3070 | } |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3071 | *dp-- = *sp--; |
| 3072 | *dp-- = *sp--; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3073 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3074 | } |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3075 | row_info->color_type = PNG_COLOR_TYPE_GRAY_ALPHA; |
| 3076 | row_info->channels = 2; |
| 3077 | row_info->pixel_depth = (png_byte)(row_info->bit_depth << 1); |
| 3078 | row_info->rowbytes = |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3079 | ((row_info->width * row_info->pixel_depth) >> 3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3080 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3081 | } |
| 3082 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB && trans_value) |
| 3083 | { |
| 3084 | if (row_info->bit_depth == 8) |
| 3085 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3086 | sp = row + (png_size_t)row_info->rowbytes - 1; |
| 3087 | dp = row + (png_size_t)(row_info->width << 2) - 1; |
| 3088 | for (i = 0; i < row_info->width; i++) |
| 3089 | { |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3090 | if (*(sp - 2) == trans_value->red && |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3091 | *(sp - 1) == trans_value->green && |
| 3092 | *(sp - 0) == trans_value->blue) |
| 3093 | *dp-- = 0; |
| 3094 | else |
| 3095 | *dp-- = 0xff; |
| 3096 | *dp-- = *sp--; |
| 3097 | *dp-- = *sp--; |
| 3098 | *dp-- = *sp--; |
| 3099 | } |
| 3100 | } |
| 3101 | else if (row_info->bit_depth == 16) |
| 3102 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3103 | sp = row + row_info->rowbytes - 1; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3104 | dp = row + (png_size_t)(row_info->width << 3) - 1; |
| 3105 | for (i = 0; i < row_info->width; i++) |
| 3106 | { |
| 3107 | if ((((png_uint_16)*(sp - 4) | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3108 | ((png_uint_16)*(sp - 5) << 8)) == trans_value->red) && |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3109 | (((png_uint_16)*(sp - 2) | |
| 3110 | ((png_uint_16)*(sp - 3) << 8)) == trans_value->green) && |
| 3111 | (((png_uint_16)*(sp - 0) | |
| 3112 | ((png_uint_16)*(sp - 1) << 8)) == trans_value->blue)) |
| 3113 | { |
| 3114 | *dp-- = 0; |
| 3115 | *dp-- = 0; |
| 3116 | } |
| 3117 | else |
| 3118 | { |
| 3119 | *dp-- = 0xff; |
| 3120 | *dp-- = 0xff; |
| 3121 | } |
| 3122 | *dp-- = *sp--; |
| 3123 | *dp-- = *sp--; |
| 3124 | *dp-- = *sp--; |
| 3125 | *dp-- = *sp--; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3126 | *dp-- = *sp--; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3127 | *dp-- = *sp--; |
| 3128 | } |
| 3129 | } |
| 3130 | row_info->color_type = PNG_COLOR_TYPE_RGB_ALPHA; |
| 3131 | row_info->channels = 4; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3132 | row_info->pixel_depth = (png_byte)(row_info->bit_depth << 2); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3133 | row_info->rowbytes = |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3134 | ((row_info->width * row_info->pixel_depth) >> 3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3135 | } |
| 3136 | } |
| 3137 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 3138 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3139 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 3140 | #if defined(PNG_READ_DITHER_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3141 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 3142 | png_do_dither(png_row_infop row_info, png_bytep row, |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3143 | png_bytep palette_lookup, png_bytep dither_lookup) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3144 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 3145 | png_bytep sp, dp; |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 3146 | png_uint_32 i; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 3147 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3148 | png_debug(1, "in png_do_dither\n"); |
| 3149 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 3150 | if (row != NULL && row_info != NULL) |
| 3151 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3152 | { |
| 3153 | if (row_info->color_type == PNG_COLOR_TYPE_RGB && |
| 3154 | palette_lookup && row_info->bit_depth == 8) |
| 3155 | { |
| 3156 | int r, g, b, p; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3157 | sp = row; |
| 3158 | dp = row; |
| 3159 | for (i = 0; i < row_info->width; i++) |
| 3160 | { |
| 3161 | r = *sp++; |
| 3162 | g = *sp++; |
| 3163 | b = *sp++; |
| 3164 | |
| 3165 | /* this looks real messy, but the compiler will reduce |
| 3166 | it down to a reasonable formula. For example, with |
| 3167 | 5 bits per color, we get: |
| 3168 | p = (((r >> 3) & 0x1f) << 10) | |
| 3169 | (((g >> 3) & 0x1f) << 5) | |
| 3170 | ((b >> 3) & 0x1f); |
| 3171 | */ |
| 3172 | p = (((r >> (8 - PNG_DITHER_RED_BITS)) & |
| 3173 | ((1 << PNG_DITHER_RED_BITS) - 1)) << |
| 3174 | (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) | |
| 3175 | (((g >> (8 - PNG_DITHER_GREEN_BITS)) & |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3176 | ((1 << PNG_DITHER_GREEN_BITS) - 1)) << |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3177 | (PNG_DITHER_BLUE_BITS)) | |
| 3178 | ((b >> (8 - PNG_DITHER_BLUE_BITS)) & |
| 3179 | ((1 << PNG_DITHER_BLUE_BITS) - 1)); |
| 3180 | |
| 3181 | *dp++ = palette_lookup[p]; |
| 3182 | } |
| 3183 | row_info->color_type = PNG_COLOR_TYPE_PALETTE; |
| 3184 | row_info->channels = 1; |
| 3185 | row_info->pixel_depth = row_info->bit_depth; |
| 3186 | row_info->rowbytes = |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3187 | ((row_info->width * row_info->pixel_depth + 7) >> 3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3188 | } |
| 3189 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA && |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3190 | palette_lookup != NULL && row_info->bit_depth == 8) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3191 | { |
| 3192 | int r, g, b, p; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3193 | sp = row; |
| 3194 | dp = row; |
| 3195 | for (i = 0; i < row_info->width; i++) |
| 3196 | { |
| 3197 | r = *sp++; |
| 3198 | g = *sp++; |
| 3199 | b = *sp++; |
| 3200 | sp++; |
| 3201 | |
| 3202 | p = (((r >> (8 - PNG_DITHER_RED_BITS)) & |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3203 | ((1 << PNG_DITHER_RED_BITS) - 1)) << |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3204 | (PNG_DITHER_GREEN_BITS + PNG_DITHER_BLUE_BITS)) | |
| 3205 | (((g >> (8 - PNG_DITHER_GREEN_BITS)) & |
| 3206 | ((1 << PNG_DITHER_GREEN_BITS) - 1)) << |
| 3207 | (PNG_DITHER_BLUE_BITS)) | |
| 3208 | ((b >> (8 - PNG_DITHER_BLUE_BITS)) & |
| 3209 | ((1 << PNG_DITHER_BLUE_BITS) - 1)); |
| 3210 | |
| 3211 | *dp++ = palette_lookup[p]; |
| 3212 | } |
| 3213 | row_info->color_type = PNG_COLOR_TYPE_PALETTE; |
| 3214 | row_info->channels = 1; |
| 3215 | row_info->pixel_depth = row_info->bit_depth; |
| 3216 | row_info->rowbytes = |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3217 | ((row_info->width * row_info->pixel_depth + 7) >> 3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3218 | } |
| 3219 | else if (row_info->color_type == PNG_COLOR_TYPE_PALETTE && |
| 3220 | dither_lookup && row_info->bit_depth == 8) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3221 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3222 | sp = row; |
| 3223 | for (i = 0; i < row_info->width; i++, sp++) |
| 3224 | { |
| 3225 | *sp = dither_lookup[*sp]; |
| 3226 | } |
| 3227 | } |
| 3228 | } |
| 3229 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 3230 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3231 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 3232 | #if defined(PNG_READ_GAMMA_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3233 | static int png_gamma_shift[] = |
| 3234 | {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0}; |
| 3235 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3236 | /* We build the 8- or 16-bit gamma tables here. Note that for 16-bit |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 3237 | * tables, we don't make a full table if we are reducing to 8-bit in |
| 3238 | * the future. Note also how the gamma_16 tables are segmented so that |
| 3239 | * we don't need to allocate > 64K chunks for a full 16-bit table. |
| 3240 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3241 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 3242 | png_build_gamma_table(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3243 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3244 | png_debug(1, "in png_build_gamma_table\n"); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3245 | if (png_ptr->bit_depth <= 8) |
| 3246 | { |
| 3247 | int i; |
| 3248 | double g; |
| 3249 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 3250 | g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3251 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3252 | png_ptr->gamma_table = (png_bytep)png_malloc(png_ptr, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3253 | (png_uint_32)256); |
| 3254 | |
| 3255 | for (i = 0; i < 256; i++) |
| 3256 | { |
| 3257 | png_ptr->gamma_table[i] = (png_byte)(pow((double)i / 255.0, |
| 3258 | g) * 255.0 + .5); |
| 3259 | } |
| 3260 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3261 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3262 | if (png_ptr->transformations & PNG_BACKGROUND) |
| 3263 | { |
| 3264 | g = 1.0 / (png_ptr->gamma); |
| 3265 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3266 | png_ptr->gamma_to_1 = (png_bytep)png_malloc(png_ptr, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3267 | (png_uint_32)256); |
| 3268 | |
| 3269 | for (i = 0; i < 256; i++) |
| 3270 | { |
| 3271 | png_ptr->gamma_to_1[i] = (png_byte)(pow((double)i / 255.0, |
| 3272 | g) * 255.0 + .5); |
| 3273 | } |
| 3274 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 3275 | g = 1.0 / (png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3276 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3277 | png_ptr->gamma_from_1 = (png_bytep)png_malloc(png_ptr, |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3278 | (png_uint_32)256); |
| 3279 | |
| 3280 | for (i = 0; i < 256; i++) |
| 3281 | { |
| 3282 | png_ptr->gamma_from_1[i] = (png_byte)(pow((double)i / 255.0, |
| 3283 | g) * 255.0 + .5); |
| 3284 | } |
| 3285 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3286 | #endif /* PNG_BACKGROUND_SUPPORTED */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3287 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3288 | else |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3289 | { |
| 3290 | double g; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3291 | int i, j, shift, num; |
| 3292 | int sig_bit; |
| 3293 | png_uint_32 ig; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3294 | |
| 3295 | if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3296 | { |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3297 | sig_bit = (int)png_ptr->sig_bit.red; |
| 3298 | if ((int)png_ptr->sig_bit.green > sig_bit) |
| 3299 | sig_bit = png_ptr->sig_bit.green; |
| 3300 | if ((int)png_ptr->sig_bit.blue > sig_bit) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3301 | sig_bit = png_ptr->sig_bit.blue; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3302 | } |
| 3303 | else |
| 3304 | { |
| 3305 | sig_bit = (int)png_ptr->sig_bit.gray; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3306 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3307 | |
| 3308 | if (sig_bit > 0) |
| 3309 | shift = 16 - sig_bit; |
| 3310 | else |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3311 | shift = 0; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3312 | |
| 3313 | if (png_ptr->transformations & PNG_16_TO_8) |
| 3314 | { |
| 3315 | if (shift < (16 - PNG_MAX_GAMMA_8)) |
| 3316 | shift = (16 - PNG_MAX_GAMMA_8); |
| 3317 | } |
| 3318 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3319 | if (shift > 8) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3320 | shift = 8; |
| 3321 | if (shift < 0) |
| 3322 | shift = 0; |
| 3323 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3324 | png_ptr->gamma_shift = (png_byte)shift; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3325 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3326 | num = (1 << (8 - shift)); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3327 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 3328 | g = 1.0 / (png_ptr->gamma * png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3329 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3330 | png_ptr->gamma_16_table = (png_uint_16pp)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3331 | (png_uint_32)(num * sizeof (png_uint_16p))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3332 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3333 | if ((png_ptr->transformations & PNG_16_TO_8) && |
| 3334 | !(png_ptr->transformations & PNG_BACKGROUND)) |
| 3335 | { |
| 3336 | double fin, fout; |
| 3337 | png_uint_32 last, max; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3338 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3339 | for (i = 0; i < num; i++) |
| 3340 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3341 | png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3342 | (png_uint_32)(256 * sizeof (png_uint_16))); |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3343 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3344 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3345 | g = 1.0 / g; |
| 3346 | last = 0; |
| 3347 | for (i = 0; i < 256; i++) |
| 3348 | { |
| 3349 | fout = ((double)i + 0.5) / 256.0; |
| 3350 | fin = pow(fout, g); |
| 3351 | max = (png_uint_32)(fin * (double)((png_uint_32)num << 8)); |
| 3352 | while (last <= max) |
| 3353 | { |
| 3354 | png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] |
| 3355 | [(int)(last >> (8 - shift))] = (png_uint_16)( |
| 3356 | (png_uint_16)i | ((png_uint_16)i << 8)); |
| 3357 | last++; |
| 3358 | } |
| 3359 | } |
| 3360 | while (last < ((png_uint_32)num << 8)) |
| 3361 | { |
| 3362 | png_ptr->gamma_16_table[(int)(last & (0xff >> shift))] |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3363 | [(int)(last >> (8 - shift))] = (png_uint_16)65535L; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3364 | last++; |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 3365 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3366 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3367 | else |
| 3368 | { |
| 3369 | for (i = 0; i < num; i++) |
| 3370 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3371 | png_ptr->gamma_16_table[i] = (png_uint_16p)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3372 | (png_uint_32)(256 * sizeof (png_uint_16))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3373 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3374 | ig = (((png_uint_32)i * (png_uint_32)png_gamma_shift[shift]) >> 4); |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 3375 | for (j = 0; j < 256; j++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3376 | { |
| 3377 | png_ptr->gamma_16_table[i][j] = |
| 3378 | (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / |
| 3379 | 65535.0, g) * 65535.0 + .5); |
| 3380 | } |
| 3381 | } |
| 3382 | } |
| 3383 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3384 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3385 | if (png_ptr->transformations & PNG_BACKGROUND) |
| 3386 | { |
| 3387 | g = 1.0 / (png_ptr->gamma); |
| 3388 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3389 | png_ptr->gamma_16_to_1 = (png_uint_16pp)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3390 | (png_uint_32)(num * sizeof (png_uint_16p ))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3391 | |
| 3392 | for (i = 0; i < num; i++) |
| 3393 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3394 | png_ptr->gamma_16_to_1[i] = (png_uint_16p)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3395 | (png_uint_32)(256 * sizeof (png_uint_16))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3396 | |
| 3397 | ig = (((png_uint_32)i * |
| 3398 | (png_uint_32)png_gamma_shift[shift]) >> 4); |
| 3399 | for (j = 0; j < 256; j++) |
| 3400 | { |
| 3401 | png_ptr->gamma_16_to_1[i][j] = |
| 3402 | (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / |
| 3403 | 65535.0, g) * 65535.0 + .5); |
| 3404 | } |
| 3405 | } |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame] | 3406 | g = 1.0 / (png_ptr->screen_gamma); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3407 | |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3408 | png_ptr->gamma_16_from_1 = (png_uint_16pp)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3409 | (png_uint_32)(num * sizeof (png_uint_16p))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3410 | |
| 3411 | for (i = 0; i < num; i++) |
| 3412 | { |
Andreas Dilger | 02ad0ef | 1997-01-17 01:34:35 -0600 | [diff] [blame] | 3413 | png_ptr->gamma_16_from_1[i] = (png_uint_16p)png_malloc(png_ptr, |
Glenn Randers-Pehrson | 0f881d6 | 1998-02-07 10:20:57 -0600 | [diff] [blame] | 3414 | (png_uint_32)(256 * sizeof (png_uint_16))); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3415 | |
| 3416 | ig = (((png_uint_32)i * |
| 3417 | (png_uint_32)png_gamma_shift[shift]) >> 4); |
| 3418 | for (j = 0; j < 256; j++) |
| 3419 | { |
| 3420 | png_ptr->gamma_16_from_1[i][j] = |
| 3421 | (png_uint_16)(pow((double)(ig + ((png_uint_32)j << 8)) / |
| 3422 | 65535.0, g) * 65535.0 + .5); |
| 3423 | } |
| 3424 | } |
| 3425 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 3426 | #endif /* PNG_BACKGROUND_SUPPORTED */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 3427 | } |
| 3428 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 3429 | #endif |
| 3430 | |