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 | /* pngwtran.c - transforms the data in a row for PNG writers |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 3 | * |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame^] | 4 | * libpng 0.98 |
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 | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame^] | 9 | * January 16, 1998 |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 10 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 11 | |
| 12 | #define PNG_INTERNAL |
| 13 | #include "png.h" |
| 14 | |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 15 | /* Transform the data according to the users wishes. The order of |
| 16 | * transformations is significant. |
| 17 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 18 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 19 | png_do_write_transformations(png_structp png_ptr) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 20 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 21 | png_debug(1, "in png_do_write_transformations\n"); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 22 | #if defined(PNG_WRITE_FILLER_SUPPORTED) |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 23 | if (png_ptr->transformations & PNG_FILLER) |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 24 | png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1, |
Guy Schalnat | e5a3779 | 1996-06-05 15:50:50 -0500 | [diff] [blame] | 25 | png_ptr->flags); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 26 | #endif |
| 27 | #if defined(PNG_WRITE_PACK_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 28 | if (png_ptr->transformations & PNG_PACK) |
| 29 | png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1, |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 30 | (png_uint_32)png_ptr->bit_depth); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 31 | #endif |
| 32 | #if defined(PNG_WRITE_SHIFT_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 33 | if (png_ptr->transformations & PNG_SHIFT) |
| 34 | png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1, |
| 35 | &(png_ptr->shift)); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 36 | #endif |
| 37 | #if defined(PNG_WRITE_SWAP_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 38 | if (png_ptr->transformations & PNG_SWAP_BYTES) |
| 39 | png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 40 | #endif |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 41 | #if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
| 42 | if (png_ptr->transformations & PNG_SWAP_ALPHA) |
| 43 | png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 44 | #endif |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame^] | 45 | #if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
| 46 | if (png_ptr->transformations & PNG_INVERT_ALPHA) |
| 47 | png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1); |
| 48 | #endif |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 49 | #if defined(PNG_WRITE_BGR_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 50 | if (png_ptr->transformations & PNG_BGR) |
| 51 | png_do_bgr(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 52 | #endif |
| 53 | #if defined(PNG_WRITE_INVERT_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 54 | if (png_ptr->transformations & PNG_INVERT_MONO) |
| 55 | png_do_invert(&(png_ptr->row_info), png_ptr->row_buf + 1); |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 56 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 57 | } |
| 58 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 59 | #if defined(PNG_WRITE_PACK_SUPPORTED) |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 60 | /* Pack pixels into bytes. Pass the true bit depth in bit_depth. The |
| 61 | * row_info bit depth should be 8 (one pixel per byte). The channels |
| 62 | * should be 1 (this only happens on grayscale and paletted images). |
| 63 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 64 | void |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 65 | png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 66 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 67 | png_debug(1, "in png_do_pack\n"); |
| 68 | if (row_info->bit_depth == 8 && |
| 69 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 70 | row != NULL && row_info != NULL && |
| 71 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 72 | row_info->channels == 1) |
| 73 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 74 | switch ((int)bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 75 | { |
| 76 | case 1: |
| 77 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 78 | png_bytep sp, dp; |
| 79 | int mask, v; |
| 80 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 81 | |
| 82 | sp = row; |
| 83 | dp = row; |
| 84 | mask = 0x80; |
| 85 | v = 0; |
| 86 | for (i = 0; i < row_info->width; i++) |
| 87 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 88 | if (*sp != 0) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 89 | v |= mask; |
| 90 | sp++; |
| 91 | if (mask > 1) |
| 92 | mask >>= 1; |
| 93 | else |
| 94 | { |
| 95 | mask = 0x80; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 96 | *dp = (png_byte)v; |
| 97 | dp++; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 98 | v = 0; |
| 99 | } |
| 100 | } |
| 101 | if (mask != 0x80) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 102 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 103 | break; |
| 104 | } |
| 105 | case 2: |
| 106 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 107 | png_bytep sp, dp; |
| 108 | int shift, v; |
| 109 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 110 | |
| 111 | sp = row; |
| 112 | dp = row; |
| 113 | shift = 6; |
| 114 | v = 0; |
| 115 | for (i = 0; i < row_info->width; i++) |
| 116 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 117 | png_byte value; |
| 118 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 119 | value = (png_byte)(*sp & 0x3); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 120 | v |= (value << shift); |
| 121 | if (shift == 0) |
| 122 | { |
| 123 | shift = 6; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 124 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 125 | dp++; |
| 126 | v = 0; |
| 127 | } |
| 128 | else |
| 129 | shift -= 2; |
| 130 | sp++; |
| 131 | } |
| 132 | if (shift != 6) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 133 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 134 | break; |
| 135 | } |
| 136 | case 4: |
| 137 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 138 | png_bytep sp, dp; |
| 139 | int shift, v; |
| 140 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 141 | |
| 142 | sp = row; |
| 143 | dp = row; |
| 144 | shift = 4; |
| 145 | v = 0; |
| 146 | for (i = 0; i < row_info->width; i++) |
| 147 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 148 | png_byte value; |
| 149 | |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 150 | value = (png_byte)(*sp & 0xf); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 151 | v |= (value << shift); |
| 152 | |
| 153 | if (shift == 0) |
| 154 | { |
| 155 | shift = 4; |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 156 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 157 | dp++; |
| 158 | v = 0; |
| 159 | } |
| 160 | else |
| 161 | shift -= 4; |
| 162 | |
| 163 | sp++; |
| 164 | } |
| 165 | if (shift != 4) |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 166 | *dp = (png_byte)v; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 167 | break; |
| 168 | } |
| 169 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 170 | row_info->bit_depth = (png_byte)bit_depth; |
| 171 | row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 172 | row_info->rowbytes = |
| 173 | ((row_info->width * row_info->pixel_depth + 7) >> 3); |
| 174 | } |
| 175 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 176 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 177 | |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 178 | #if defined(PNG_WRITE_SHIFT_SUPPORTED) |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 179 | /* Shift pixel values to take advantage of whole range. Pass the |
| 180 | * true number of bits in bit_depth. The row should be packed |
| 181 | * according to row_info->bit_depth. Thus, if you had a row of |
| 182 | * bit depth 4, but the pixels only had values from 0 to 7, you |
| 183 | * would pass 3 as bit_depth, and this routine would translate the |
| 184 | * data to 0 to 15. |
| 185 | */ |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 186 | void |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 187 | png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 188 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 189 | png_debug(1, "in png_do_shift\n"); |
| 190 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 191 | if (row != NULL && row_info != NULL && |
| 192 | #else |
| 193 | if ( |
| 194 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 195 | row_info->color_type != PNG_COLOR_TYPE_PALETTE) |
| 196 | { |
| 197 | int shift_start[4], shift_dec[4]; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 198 | png_uint_32 channels; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 199 | |
| 200 | channels = 0; |
| 201 | if (row_info->color_type & PNG_COLOR_MASK_COLOR) |
| 202 | { |
| 203 | shift_start[channels] = row_info->bit_depth - bit_depth->red; |
| 204 | shift_dec[channels] = bit_depth->red; |
| 205 | channels++; |
| 206 | shift_start[channels] = row_info->bit_depth - bit_depth->green; |
| 207 | shift_dec[channels] = bit_depth->green; |
| 208 | channels++; |
| 209 | shift_start[channels] = row_info->bit_depth - bit_depth->blue; |
| 210 | shift_dec[channels] = bit_depth->blue; |
| 211 | channels++; |
| 212 | } |
| 213 | else |
| 214 | { |
| 215 | shift_start[channels] = row_info->bit_depth - bit_depth->gray; |
| 216 | shift_dec[channels] = bit_depth->gray; |
| 217 | channels++; |
| 218 | } |
| 219 | if (row_info->color_type & PNG_COLOR_MASK_ALPHA) |
| 220 | { |
| 221 | shift_start[channels] = row_info->bit_depth - bit_depth->alpha; |
| 222 | shift_dec[channels] = bit_depth->alpha; |
| 223 | channels++; |
| 224 | } |
| 225 | |
| 226 | /* with low row dephts, could only be grayscale, so one channel */ |
| 227 | if (row_info->bit_depth < 8) |
| 228 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 229 | png_bytep bp; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 230 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 231 | png_byte mask; |
| 232 | |
| 233 | if (bit_depth->gray == 1 && row_info->bit_depth == 2) |
| 234 | mask = 0x55; |
| 235 | else if (row_info->bit_depth == 4 && bit_depth->gray == 3) |
| 236 | mask = 0x11; |
| 237 | else |
| 238 | mask = 0xff; |
| 239 | |
| 240 | for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++) |
| 241 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 242 | png_uint_16 v; |
| 243 | int j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 244 | |
| 245 | v = *bp; |
| 246 | *bp = 0; |
| 247 | for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) |
| 248 | { |
| 249 | if (j > 0) |
| 250 | *bp |= (png_byte)((v << j) & 0xff); |
| 251 | else |
| 252 | *bp |= (png_byte)((v >> (-j)) & mask); |
| 253 | } |
| 254 | } |
| 255 | } |
| 256 | else if (row_info->bit_depth == 8) |
| 257 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 258 | png_bytep bp; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 259 | png_uint_32 i; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 260 | |
| 261 | for (bp = row, i = 0; i < row_info->width; i++) |
| 262 | { |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 263 | png_uint_32 c; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 264 | |
| 265 | for (c = 0; c < channels; c++, bp++) |
| 266 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 267 | png_uint_16 v; |
| 268 | int j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 269 | |
| 270 | v = *bp; |
| 271 | *bp = 0; |
| 272 | for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) |
| 273 | { |
| 274 | if (j > 0) |
| 275 | *bp |= (png_byte)((v << j) & 0xff); |
| 276 | else |
| 277 | *bp |= (png_byte)((v >> (-j)) & 0xff); |
| 278 | } |
| 279 | } |
| 280 | } |
| 281 | } |
| 282 | else |
| 283 | { |
Guy Schalnat | 6d76471 | 1995-12-19 03:22:19 -0600 | [diff] [blame] | 284 | png_bytep bp; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 285 | png_uint_32 i; |
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 | for (bp = row, i = 0; i < row_info->width * row_info->channels; i++) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 288 | { |
Glenn Randers-Pehrson | b6ce43d | 1998-01-01 07:13:13 -0600 | [diff] [blame] | 289 | png_uint_32 c; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 290 | |
| 291 | for (c = 0; c < channels; c++, bp += 2) |
| 292 | { |
| 293 | png_uint_16 value, v; |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 294 | int j; |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 295 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 296 | v = ((png_uint_16)(*bp) << 8) + *(bp + 1); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 297 | value = 0; |
| 298 | for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) |
| 299 | { |
| 300 | if (j > 0) |
| 301 | value |= (png_uint_16)((v << j) & (png_uint_16)0xffff); |
| 302 | else |
| 303 | value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff); |
| 304 | } |
Guy Schalnat | b2e01bd | 1996-01-26 01:38:47 -0600 | [diff] [blame] | 305 | *bp = (png_byte)(value >> 8); |
Guy Schalnat | 4ee97b0 | 1996-01-16 01:51:56 -0600 | [diff] [blame] | 306 | *(bp + 1) = (png_byte)(value & 0xff); |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 307 | } |
| 308 | } |
| 309 | } |
| 310 | } |
| 311 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 312 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 313 | |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 314 | #if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 315 | void |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 316 | png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 317 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 318 | png_debug(1, "in png_do_write_swap_alpha\n"); |
| 319 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 320 | if (row != NULL && row_info != NULL) |
| 321 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 322 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 323 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 324 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 325 | /* This converts from ARGB to RGBA */ |
| 326 | if (row_info->bit_depth == 8) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 327 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 328 | png_bytep sp, dp; |
| 329 | png_byte save; |
| 330 | png_uint_32 i; |
| 331 | |
| 332 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 333 | { |
| 334 | save = *(sp++); |
| 335 | *(dp++) = *(sp++); |
| 336 | *(dp++) = *(sp++); |
| 337 | *(dp++) = *(sp++); |
| 338 | *(dp++) = save; |
| 339 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 340 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 341 | /* This converts from AARRGGBB to RRGGBBAA */ |
| 342 | else |
| 343 | { |
| 344 | png_bytep sp, dp; |
| 345 | png_byte save[2]; |
| 346 | png_uint_32 i; |
| 347 | |
| 348 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 349 | { |
| 350 | save[0] = *(sp++); |
| 351 | save[1] = *(sp++); |
| 352 | *(dp++) = *(sp++); |
| 353 | *(dp++) = *(sp++); |
| 354 | *(dp++) = *(sp++); |
| 355 | *(dp++) = *(sp++); |
| 356 | *(dp++) = *(sp++); |
| 357 | *(dp++) = *(sp++); |
| 358 | *(dp++) = save[0]; |
| 359 | *(dp++) = save[1]; |
| 360 | } |
| 361 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 362 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 363 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 364 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 365 | /* This converts from AG to GA */ |
| 366 | if (row_info->bit_depth == 8) |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 367 | { |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 368 | png_bytep sp, dp; |
| 369 | png_byte save; |
| 370 | png_uint_32 i; |
| 371 | |
| 372 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 373 | { |
| 374 | save = *(sp++); |
| 375 | *(dp++) = *(sp++); |
| 376 | *(dp++) = save; |
| 377 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 378 | } |
Andreas Dilger | 47a0c42 | 1997-05-16 02:46:07 -0500 | [diff] [blame] | 379 | /* This converts from AAGG to GGAA */ |
| 380 | else |
| 381 | { |
| 382 | png_bytep sp, dp; |
| 383 | png_byte save[2]; |
| 384 | png_uint_32 i; |
| 385 | |
| 386 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 387 | { |
| 388 | save[0] = *(sp++); |
| 389 | save[1] = *(sp++); |
| 390 | *(dp++) = *(sp++); |
| 391 | *(dp++) = *(sp++); |
| 392 | *(dp++) = save[0]; |
| 393 | *(dp++) = save[1]; |
| 394 | } |
| 395 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 396 | } |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 397 | } |
| 398 | } |
Guy Schalnat | 51f0eb4 | 1995-09-26 05:22:39 -0500 | [diff] [blame] | 399 | #endif |
Guy Schalnat | 0d58058 | 1995-07-20 02:43:20 -0500 | [diff] [blame] | 400 | |
Glenn Randers-Pehrson | c4a2ae6 | 1998-01-16 22:06:18 -0600 | [diff] [blame^] | 401 | #if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
| 402 | void |
| 403 | png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) |
| 404 | { |
| 405 | png_debug(1, "in png_do_write_invert_alpha\n"); |
| 406 | #if defined(PNG_USELESS_TESTS_SUPPORTED) |
| 407 | if (row != NULL && row_info != NULL) |
| 408 | #endif |
| 409 | { |
| 410 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
| 411 | { |
| 412 | /* This inverts the alpha channel in RGBA */ |
| 413 | if (row_info->bit_depth == 8) |
| 414 | { |
| 415 | png_bytep sp, dp; |
| 416 | png_uint_32 i; |
| 417 | |
| 418 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 419 | { |
| 420 | *(dp++) = *(sp++); |
| 421 | *(dp++) = *(sp++); |
| 422 | *(dp++) = *(sp++); |
| 423 | *(dp++) = 255 - *(sp++); |
| 424 | } |
| 425 | } |
| 426 | /* This inverts the alpha channel in RRGGBBAA */ |
| 427 | else |
| 428 | { |
| 429 | png_bytep sp, dp; |
| 430 | png_uint_32 i; |
| 431 | |
| 432 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 433 | { |
| 434 | *(dp++) = *(sp++); |
| 435 | *(dp++) = *(sp++); |
| 436 | *(dp++) = *(sp++); |
| 437 | *(dp++) = *(sp++); |
| 438 | *(dp++) = *(sp++); |
| 439 | *(dp++) = *(sp++); |
| 440 | *(dp++) = 255 - *(sp++); |
| 441 | *(dp++) = 255 - *(sp++); |
| 442 | } |
| 443 | } |
| 444 | } |
| 445 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
| 446 | { |
| 447 | /* This inverts the alpha channel in GA */ |
| 448 | if (row_info->bit_depth == 8) |
| 449 | { |
| 450 | png_bytep sp, dp; |
| 451 | png_uint_32 i; |
| 452 | |
| 453 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 454 | { |
| 455 | *(dp++) = *(sp++); |
| 456 | *(dp++) = 255 - *(sp++); |
| 457 | } |
| 458 | } |
| 459 | /* This inverts the alpha channel in GGAA */ |
| 460 | else |
| 461 | { |
| 462 | png_bytep sp, dp; |
| 463 | png_uint_32 i; |
| 464 | |
| 465 | for (i = 0, sp = dp = row; i < row_info->width; i++) |
| 466 | { |
| 467 | *(dp++) = *(sp++); |
| 468 | *(dp++) = *(sp++); |
| 469 | *(dp++) = 255 - *(sp++); |
| 470 | *(dp++) = 255 - *(sp++); |
| 471 | } |
| 472 | } |
| 473 | } |
| 474 | } |
| 475 | } |
| 476 | #endif |