├── .gitignore ├── LICENSE ├── README.md ├── build.sh ├── img2term.c ├── imgs ├── thumbnail.png └── tsodinPog.png └── thirdparty ├── stb_image.h └── stb_image_resize.h /.gitignore: -------------------------------------------------------------------------------- 1 | img2term -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Copyright 2022 Alexey Kutepov 2 | 3 | Permission is hereby granted, free of charge, to any person obtaining 4 | a copy of this software and associated documentation files (the 5 | "Software"), to deal in the Software without restriction, including 6 | without limitation the rights to use, copy, modify, merge, publish, 7 | distribute, sublicense, and/or sell copies of the Software, and to 8 | permit persons to whom the Software is furnished to do so, subject to 9 | the following conditions: 10 | 11 | The above copyright notice and this permission notice shall be 12 | included in all copies or substantial portions of the Software. 13 | 14 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 15 | EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 16 | MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 17 | NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 18 | LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 19 | OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 20 | WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # img2term 2 | 3 | Print images in the terminal using the [term 256 colors](https://www.ditig.com/256-colors-cheat-sheet) 4 | 5 | ![thumbnail](./imgs/thumbnail.png) 6 | 7 | ## Quick Start 8 | 9 | ```console 10 | $ ./build.sh 11 | $ ./img2term ./imgs/tsodinPog.png 12 | ``` 13 | -------------------------------------------------------------------------------- /build.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | set -xe 4 | 5 | cc -I./thirdparty/ -o img2term img2term.c -lm 6 | -------------------------------------------------------------------------------- /img2term.c: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | #include 4 | #define STB_IMAGE_IMPLEMENTATION 5 | #include "stb_image.h" 6 | #define STB_IMAGE_RESIZE_IMPLEMENTATION 7 | #include "stb_image_resize.h" 8 | 9 | #define DEFAULT_WIDTH 32 10 | 11 | int hsl256[][3] = { 12 | {0, 0, 0}, 13 | {0, 100, 25}, 14 | {120, 100, 25}, 15 | {60, 100, 25}, 16 | {240, 100, 25}, 17 | {300, 100, 25}, 18 | {180, 100, 25}, 19 | {0, 0, 75}, 20 | {0, 0, 50}, 21 | {0, 100, 50}, 22 | {120, 100, 50}, 23 | {60, 100, 50}, 24 | {240, 100, 50}, 25 | {300, 100, 50}, 26 | {180, 100, 50}, 27 | {0, 0, 100}, 28 | {0, 0, 0}, 29 | {240, 99, 18}, 30 | {240, 100, 26}, 31 | {240, 100, 34}, 32 | {240, 100, 42}, 33 | {240, 100, 50}, 34 | {120, 99, 18}, 35 | {180, 99, 18}, 36 | {197, 100, 26}, 37 | {207, 100, 34}, 38 | {213, 100, 42}, 39 | {217, 100, 50}, 40 | {120, 100, 26}, 41 | {162, 100, 26}, 42 | {180, 100, 26}, 43 | {193, 100, 34}, 44 | {202, 100, 42}, 45 | {208, 100, 50}, 46 | {120, 100, 34}, 47 | {152, 100, 34}, 48 | {166, 100, 34}, 49 | {180, 100, 34}, 50 | {191, 100, 42}, 51 | {198, 100, 50}, 52 | {120, 100, 42}, 53 | {146, 100, 42}, 54 | {157, 100, 42}, 55 | {168, 100, 42}, 56 | {180, 100, 42}, 57 | {189, 100, 50}, 58 | {120, 100, 50}, 59 | {142, 100, 50}, 60 | {151, 100, 50}, 61 | {161, 100, 50}, 62 | {170, 100, 50}, 63 | {180, 100, 50}, 64 | {0, 99, 18}, 65 | {300, 99, 18}, 66 | {282, 100, 26}, 67 | {272, 100, 34}, 68 | {266, 100, 42}, 69 | {262, 100, 50}, 70 | {60, 99, 18}, 71 | {0, 0, 37}, 72 | {240, 17, 45}, 73 | {240, 33, 52}, 74 | {240, 60, 60}, 75 | {240, 100, 68}, 76 | {77, 100, 26}, 77 | {120, 17, 45}, 78 | {180, 17, 45}, 79 | {210, 33, 52}, 80 | {220, 60, 60}, 81 | {225, 100, 68}, 82 | {87, 100, 34}, 83 | {120, 33, 52}, 84 | {150, 33, 52}, 85 | {180, 33, 52}, 86 | {200, 60, 60}, 87 | {210, 100, 68}, 88 | {93, 100, 42}, 89 | {120, 60, 60}, 90 | {140, 60, 60}, 91 | {160, 60, 60}, 92 | {180, 60, 60}, 93 | {195, 100, 68}, 94 | {97, 100, 50}, 95 | {120, 100, 68}, 96 | {135, 100, 68}, 97 | {150, 100, 68}, 98 | {165, 100, 68}, 99 | {180, 100, 68}, 100 | {0, 100, 26}, 101 | {317, 100, 26}, 102 | {300, 100, 26}, 103 | {286, 100, 34}, 104 | {277, 100, 42}, 105 | {271, 100, 50}, 106 | {42, 100, 26}, 107 | {0, 17, 45}, 108 | {300, 17, 45}, 109 | {270, 33, 52}, 110 | {260, 60, 60}, 111 | {255, 100, 68}, 112 | {60, 100, 26}, 113 | {60, 17, 45}, 114 | {0, 0, 52}, 115 | {240, 20, 60}, 116 | {240, 50, 68}, 117 | {240, 100, 76}, 118 | {73, 100, 34}, 119 | {90, 33, 52}, 120 | {120, 20, 60}, 121 | {180, 20, 60}, 122 | {210, 50, 68}, 123 | {220, 100, 76}, 124 | {82, 100, 42}, 125 | {100, 60, 60}, 126 | {120, 50, 68}, 127 | {150, 50, 68}, 128 | {180, 50, 68}, 129 | {200, 100, 76}, 130 | {88, 100, 50}, 131 | {105, 100, 68}, 132 | {120, 100, 76}, 133 | {140, 100, 76}, 134 | {160, 100, 76}, 135 | {180, 100, 76}, 136 | {0, 100, 34}, 137 | {327, 100, 34}, 138 | {313, 100, 34}, 139 | {300, 100, 34}, 140 | {288, 100, 42}, 141 | {281, 100, 50}, 142 | {32, 100, 34}, 143 | {0, 33, 52}, 144 | {330, 33, 52}, 145 | {300, 33, 52}, 146 | {280, 60, 60}, 147 | {270, 100, 68}, 148 | {46, 100, 34}, 149 | {30, 33, 52}, 150 | {0, 20, 60}, 151 | {300, 20, 60}, 152 | {270, 50, 68}, 153 | {260, 100, 76}, 154 | {60, 100, 34}, 155 | {60, 33, 52}, 156 | {60, 20, 60}, 157 | {0, 0, 68}, 158 | {240, 33, 76}, 159 | {240, 100, 84}, 160 | {71, 100, 42}, 161 | {80, 60, 60}, 162 | {90, 50, 68}, 163 | {120, 33, 76}, 164 | {180, 33, 76}, 165 | {210, 100, 84}, 166 | {78, 100, 50}, 167 | {90, 100, 68}, 168 | {100, 100, 76}, 169 | {120, 100, 84}, 170 | {150, 100, 84}, 171 | {180, 100, 84}, 172 | {0, 100, 42}, 173 | {333, 100, 42}, 174 | {322, 100, 42}, 175 | {311, 100, 42}, 176 | {300, 100, 42}, 177 | {290, 100, 50}, 178 | {26, 100, 42}, 179 | {0, 60, 60}, 180 | {340, 60, 60}, 181 | {320, 60, 60}, 182 | {300, 60, 60}, 183 | {285, 100, 68}, 184 | {37, 100, 42}, 185 | {20, 60, 60}, 186 | {0, 50, 68}, 187 | {330, 50, 68}, 188 | {300, 50, 68}, 189 | {280, 100, 76}, 190 | {48, 100, 42}, 191 | {40, 60, 60}, 192 | {30, 50, 68}, 193 | {0, 33, 76}, 194 | {300, 33, 76}, 195 | {270, 100, 84}, 196 | {60, 100, 42}, 197 | {60, 60, 60}, 198 | {60, 50, 68}, 199 | {60, 33, 76}, 200 | {0, 0, 84}, 201 | {240, 100, 92}, 202 | {69, 100, 50}, 203 | {75, 100, 68}, 204 | {80, 100, 76}, 205 | {90, 100, 84}, 206 | {120, 100, 92}, 207 | {180, 100, 92}, 208 | {0, 100, 50}, 209 | {337, 100, 50}, 210 | {328, 100, 50}, 211 | {318, 100, 50}, 212 | {309, 100, 50}, 213 | {300, 100, 50}, 214 | {22, 100, 50}, 215 | {0, 100, 68}, 216 | {345, 100, 68}, 217 | {330, 100, 68}, 218 | {315, 100, 68}, 219 | {300, 100, 68}, 220 | {31, 100, 50}, 221 | {15, 100, 68}, 222 | {0, 100, 76}, 223 | {340, 100, 76}, 224 | {320, 100, 76}, 225 | {300, 100, 76}, 226 | {41, 100, 50}, 227 | {30, 100, 68}, 228 | {20, 100, 76}, 229 | {0, 100, 84}, 230 | {330, 100, 84}, 231 | {300, 100, 84}, 232 | {50, 100, 50}, 233 | {45, 100, 68}, 234 | {40, 100, 76}, 235 | {30, 100, 84}, 236 | {0, 100, 92}, 237 | {300, 100, 92}, 238 | {60, 100, 50}, 239 | {60, 100, 68}, 240 | {60, 100, 76}, 241 | {60, 100, 84}, 242 | {60, 100, 92}, 243 | {0, 0, 100}, 244 | {0, 0, 3}, 245 | {0, 0, 7}, 246 | {0, 0, 10}, 247 | {0, 0, 14}, 248 | {0, 0, 18}, 249 | {0, 0, 22}, 250 | {0, 0, 26}, 251 | {0, 0, 30}, 252 | {0, 0, 34}, 253 | {0, 0, 38}, 254 | {0, 0, 42}, 255 | {0, 0, 46}, 256 | {0, 0, 50}, 257 | {0, 0, 54}, 258 | {0, 0, 58}, 259 | {0, 0, 61}, 260 | {0, 0, 65}, 261 | {0, 0, 69}, 262 | {0, 0, 73}, 263 | {0, 0, 77}, 264 | {0, 0, 81}, 265 | {0, 0, 85}, 266 | {0, 0, 89}, 267 | {0, 0, 93}, 268 | }; 269 | 270 | int rgb256[][3] = { 271 | {0,0,0}, 272 | {128,0,0}, 273 | {0,128,0}, 274 | {128,128,0}, 275 | {0,0,128}, 276 | {128,0,128}, 277 | {0,128,128}, 278 | {192,192,192}, 279 | {128,128,128}, 280 | {255,0,0}, 281 | {0,255,0}, 282 | {255,255,0}, 283 | {0,0,255}, 284 | {255,0,255}, 285 | {0,255,255}, 286 | {255,255,255}, 287 | {0,0,0}, 288 | {0,0,95}, 289 | {0,0,135}, 290 | {0,0,175}, 291 | {0,0,215}, 292 | {0,0,255}, 293 | {0,95,0}, 294 | {0,95,95}, 295 | {0,95,135}, 296 | {0,95,175}, 297 | {0,95,215}, 298 | {0,95,255}, 299 | {0,135,0}, 300 | {0,135,95}, 301 | {0,135,135}, 302 | {0,135,175}, 303 | {0,135,215}, 304 | {0,135,255}, 305 | {0,175,0}, 306 | {0,175,95}, 307 | {0,175,135}, 308 | {0,175,175}, 309 | {0,175,215}, 310 | {0,175,255}, 311 | {0,215,0}, 312 | {0,215,95}, 313 | {0,215,135}, 314 | {0,215,175}, 315 | {0,215,215}, 316 | {0,215,255}, 317 | {0,255,0}, 318 | {0,255,95}, 319 | {0,255,135}, 320 | {0,255,175}, 321 | {0,255,215}, 322 | {0,255,255}, 323 | {95,0,0}, 324 | {95,0,95}, 325 | {95,0,135}, 326 | {95,0,175}, 327 | {95,0,215}, 328 | {95,0,255}, 329 | {95,95,0}, 330 | {95,95,95}, 331 | {95,95,135}, 332 | {95,95,175}, 333 | {95,95,215}, 334 | {95,95,255}, 335 | {95,135,0}, 336 | {95,135,95}, 337 | {95,135,135}, 338 | {95,135,175}, 339 | {95,135,215}, 340 | {95,135,255}, 341 | {95,175,0}, 342 | {95,175,95}, 343 | {95,175,135}, 344 | {95,175,175}, 345 | {95,175,215}, 346 | {95,175,255}, 347 | {95,215,0}, 348 | {95,215,95}, 349 | {95,215,135}, 350 | {95,215,175}, 351 | {95,215,215}, 352 | {95,215,255}, 353 | {95,255,0}, 354 | {95,255,95}, 355 | {95,255,135}, 356 | {95,255,175}, 357 | {95,255,215}, 358 | {95,255,255}, 359 | {135,0,0}, 360 | {135,0,95}, 361 | {135,0,135}, 362 | {135,0,175}, 363 | {135,0,215}, 364 | {135,0,255}, 365 | {135,95,0}, 366 | {135,95,95}, 367 | {135,95,135}, 368 | {135,95,175}, 369 | {135,95,215}, 370 | {135,95,255}, 371 | {135,135,0}, 372 | {135,135,95}, 373 | {135,135,135}, 374 | {135,135,175}, 375 | {135,135,215}, 376 | {135,135,255}, 377 | {135,175,0}, 378 | {135,175,95}, 379 | {135,175,135}, 380 | {135,175,175}, 381 | {135,175,215}, 382 | {135,175,255}, 383 | {135,215,0}, 384 | {135,215,95}, 385 | {135,215,135}, 386 | {135,215,175}, 387 | {135,215,215}, 388 | {135,215,255}, 389 | {135,255,0}, 390 | {135,255,95}, 391 | {135,255,135}, 392 | {135,255,175}, 393 | {135,255,215}, 394 | {135,255,255}, 395 | {175,0,0}, 396 | {175,0,95}, 397 | {175,0,135}, 398 | {175,0,175}, 399 | {175,0,215}, 400 | {175,0,255}, 401 | {175,95,0}, 402 | {175,95,95}, 403 | {175,95,135}, 404 | {175,95,175}, 405 | {175,95,215}, 406 | {175,95,255}, 407 | {175,135,0}, 408 | {175,135,95}, 409 | {175,135,135}, 410 | {175,135,175}, 411 | {175,135,215}, 412 | {175,135,255}, 413 | {175,175,0}, 414 | {175,175,95}, 415 | {175,175,135}, 416 | {175,175,175}, 417 | {175,175,215}, 418 | {175,175,255}, 419 | {175,215,0}, 420 | {175,215,95}, 421 | {175,215,135}, 422 | {175,215,175}, 423 | {175,215,215}, 424 | {175,215,255}, 425 | {175,255,0}, 426 | {175,255,95}, 427 | {175,255,135}, 428 | {175,255,175}, 429 | {175,255,215}, 430 | {175,255,255}, 431 | {215,0,0}, 432 | {215,0,95}, 433 | {215,0,135}, 434 | {215,0,175}, 435 | {215,0,215}, 436 | {215,0,255}, 437 | {215,95,0}, 438 | {215,95,95}, 439 | {215,95,135}, 440 | {215,95,175}, 441 | {215,95,215}, 442 | {215,95,255}, 443 | {215,135,0}, 444 | {215,135,95}, 445 | {215,135,135}, 446 | {215,135,175}, 447 | {215,135,215}, 448 | {215,135,255}, 449 | {215,175,0}, 450 | {215,175,95}, 451 | {215,175,135}, 452 | {215,175,175}, 453 | {215,175,215}, 454 | {215,175,255}, 455 | {215,215,0}, 456 | {215,215,95}, 457 | {215,215,135}, 458 | {215,215,175}, 459 | {215,215,215}, 460 | {215,215,255}, 461 | {215,255,0}, 462 | {215,255,95}, 463 | {215,255,135}, 464 | {215,255,175}, 465 | {215,255,215}, 466 | {215,255,255}, 467 | {255,0,0}, 468 | {255,0,95}, 469 | {255,0,135}, 470 | {255,0,175}, 471 | {255,0,215}, 472 | {255,0,255}, 473 | {255,95,0}, 474 | {255,95,95}, 475 | {255,95,135}, 476 | {255,95,175}, 477 | {255,95,215}, 478 | {255,95,255}, 479 | {255,135,0}, 480 | {255,135,95}, 481 | {255,135,135}, 482 | {255,135,175}, 483 | {255,135,215}, 484 | {255,135,255}, 485 | {255,175,0}, 486 | {255,175,95}, 487 | {255,175,135}, 488 | {255,175,175}, 489 | {255,175,215}, 490 | {255,175,255}, 491 | {255,215,0}, 492 | {255,215,95}, 493 | {255,215,135}, 494 | {255,215,175}, 495 | {255,215,215}, 496 | {255,215,255}, 497 | {255,255,0}, 498 | {255,255,95}, 499 | {255,255,135}, 500 | {255,255,175}, 501 | {255,255,215}, 502 | {255,255,255}, 503 | {8,8,8}, 504 | {18,18,18}, 505 | {28,28,28}, 506 | {38,38,38}, 507 | {48,48,48}, 508 | {58,58,58}, 509 | {68,68,68}, 510 | {78,78,78}, 511 | {88,88,88}, 512 | {98,98,98}, 513 | {108,108,108}, 514 | {118,118,118}, 515 | {128,128,128}, 516 | {138,138,138}, 517 | {148,148,148}, 518 | {158,158,158}, 519 | {168,168,168}, 520 | {178,178,178}, 521 | {188,188,188}, 522 | {198,198,198}, 523 | {208,208,208}, 524 | {218,218,218}, 525 | {228,228,228}, 526 | {238,238,238}, 527 | }; 528 | 529 | static void rgb_to_hsl(int r, int g, int b, int *h, int *s, int *l) 530 | { 531 | float r01 = r/255.0f; 532 | float g01 = g/255.0f; 533 | float b01 = b/255.0f; 534 | float cmax = r01; 535 | if (g01 > cmax) cmax = g01; 536 | if (b01 > cmax) cmax = b01; 537 | float cmin = r01; 538 | if (g01 < cmin) cmin = g01; 539 | if (b01 < cmin) cmin = b01; 540 | float delta = cmax - cmin; 541 | float epsilon = 1e-6; 542 | float hf = 0; 543 | if (delta < epsilon) hf = 0; 544 | else if (cmax == r01) hf = 60.0f*fmod((g01 - b01)/delta, 6.0f); 545 | else if (cmax == g01) hf = 60.0f*((b01 - r01)/delta + 2); 546 | else if (cmax == b01) hf = 60.0f*((r01 - g01)/delta + 4); 547 | else assert(0 && "unreachable"); 548 | 549 | float lf = (cmax + cmin)/2; 550 | 551 | float sf = 0; 552 | if (delta < epsilon) sf = 0; 553 | else sf = delta/(1 - fabsf(2*lf - 1)); 554 | 555 | *h = fmodf(fmodf(hf, 360.0f) + 360.0f, 360.0f); 556 | *s = sf*100.0f; 557 | *l = lf*100.0f; 558 | } 559 | 560 | static int distance256(int table256[256][3], int i, int a, int b, int c) 561 | { 562 | int da = a - table256[i][0]; 563 | int db = b - table256[i][1]; 564 | int dc = c - table256[i][2]; 565 | return da*da + db*db + dc*dc; 566 | } 567 | 568 | static int find_ansi_index(int table256[256][3], int a, int b, int c) 569 | { 570 | int index = 0; 571 | for (int i = 0; i < 256; ++i) { 572 | if (distance256(table256, i, a, b, c) < distance256(table256, index, a, b, c)) { 573 | index = i; 574 | } 575 | } 576 | return index; 577 | } 578 | 579 | static char *shift_args(int *argc, char ***argv) 580 | { 581 | assert(*argc > 0); 582 | char *result = **argv; 583 | *argc -= 1; 584 | *argv += 1; 585 | return result; 586 | } 587 | 588 | typedef enum { 589 | DIST_HSL, 590 | DIST_RGB, 591 | } Distance; 592 | 593 | void usage(const char *program) 594 | { 595 | fprintf(stderr, "Usage: %s [OPTIONS...] [FILES...]\n", program); 596 | fprintf(stderr, "Options:\n"); 597 | fprintf(stderr, " -w width of the image default is %d\n", DEFAULT_WIDTH); 598 | fprintf(stderr, " -rgb search nearest color in RGB space\n"); 599 | fprintf(stderr, " -hsl search nearest color in HSL space (default)\n"); 600 | fprintf(stderr, " -h print this help and exit\n"); 601 | fprintf(stderr, "Example:\n"); 602 | fprintf(stderr, " $ %s -w 16 image1.png -rgb -w 32 image2.png\n", program); 603 | fprintf(stderr, " Print image1.png with width 16 and HSL search space then \n"); 604 | fprintf(stderr, " print image2.png with widht 32 and RGB search space.\n"); 605 | fprintf(stderr, " Each flags override the previous one.\n"); 606 | } 607 | 608 | int main(int argc, char **argv) 609 | { 610 | // TODO: Add 16 colors support 611 | // TODO: Add TrueColor support 612 | assert(argc > 0); 613 | const char *program = shift_args(&argc, &argv); 614 | 615 | int resized_width = DEFAULT_WIDTH; 616 | Distance distance = DIST_HSL; 617 | 618 | // TODO: throw an error if not a single file was provided 619 | while (argc > 0) { 620 | const char *flag = shift_args(&argc, &argv); 621 | if (strcmp(flag, "-w") == 0) { 622 | if (argc <= 0) { 623 | fprintf(stderr, "ERROR: no value is provided for %s\n", flag); 624 | exit(1); 625 | } 626 | 627 | resized_width = atoi(shift_args(&argc, &argv)); 628 | 629 | if (resized_width < 0) { 630 | fprintf(stderr, "ERROR: the value of %s can't be negative\n", flag); 631 | exit(1); 632 | } 633 | } else if (strcmp(flag, "-rgb") == 0) { 634 | distance = DIST_RGB; 635 | } else if (strcmp(flag, "-hsl") == 0) { 636 | distance = DIST_HSL; 637 | } else if (strcmp(flag, "-h") == 0) { 638 | usage(program); 639 | exit(0); 640 | } else { 641 | const char *file_path = flag; 642 | 643 | int width, height; 644 | uint32_t *pixels = (uint32_t*)stbi_load(file_path, &width, &height, NULL, 4); 645 | if (pixels == NULL) { 646 | fprintf(stderr, "ERROR: could not read file %s\n", file_path); 647 | continue; 648 | } 649 | 650 | int resized_height = height*resized_width/width; 651 | 652 | // TODO: maybe use a custom resize algorithm that does not require any memory allocation? 653 | // Similar to how olive.c resize the sprites. 654 | // (Though stb_image_resize supports a lot of fancy filters and stuff which we may try 655 | // to utilize to improve the results) 656 | uint32_t *resized_pixels = malloc(sizeof(uint32_t)*resized_width*resized_height); 657 | if (resized_pixels == NULL) { 658 | fprintf(stderr, "ERROR: could not allocate memory for resized image\n"); 659 | exit(1); 660 | } 661 | 662 | // TODO: stbir_resize_uint8 returns int, which means it can fail. We should check for that. 663 | stbir_resize_uint8( 664 | (const unsigned char*)pixels, width, height, sizeof(uint32_t)*width, 665 | (unsigned char*)resized_pixels, resized_width, resized_height, sizeof(uint32_t)*resized_width, 666 | 4); 667 | 668 | for (int y = 0; y < resized_height; ++y) { 669 | for (int x = 0; x < resized_width; ++x) { 670 | uint32_t pixel = resized_pixels[y*resized_width + x]; 671 | int r = (pixel>>8*0)&0xFF; 672 | int g = (pixel>>8*1)&0xFF; 673 | int b = (pixel>>8*2)&0xFF; 674 | int a = (pixel>>8*3)&0xFF; 675 | r = a*r/255; 676 | g = a*g/255; 677 | b = a*b/255; 678 | switch (distance) { 679 | case DIST_HSL: { 680 | int h, s, l; 681 | rgb_to_hsl(r, g, b, &h, &s, &l); 682 | printf("\e[48;5;%dm ", find_ansi_index(hsl256, h, s, l)); 683 | } break; 684 | 685 | case DIST_RGB: { 686 | printf("\e[48;5;%dm ", find_ansi_index(rgb256, r, g, b)); 687 | } break; 688 | 689 | default: assert(0 && "unreachable"); 690 | } 691 | } 692 | printf("\e[0m\n"); 693 | } 694 | printf("\e[0m\n"); 695 | 696 | free(resized_pixels); 697 | stbi_image_free(pixels); 698 | } 699 | } 700 | 701 | return 0; 702 | } 703 | // TODO: automated testing 704 | // Since the whole behaviour of the program is represented by its stdout, it should be pretty easy to have some autotests 705 | -------------------------------------------------------------------------------- /imgs/thumbnail.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/tsoding/img2term/082d00943af043a43f6a7a133ecda18e586b5c39/imgs/thumbnail.png -------------------------------------------------------------------------------- /imgs/tsodinPog.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/tsoding/img2term/082d00943af043a43f6a7a133ecda18e586b5c39/imgs/tsodinPog.png -------------------------------------------------------------------------------- /thirdparty/stb_image_resize.h: -------------------------------------------------------------------------------- 1 | /* stb_image_resize - v0.97 - public domain image resizing 2 | by Jorge L Rodriguez (@VinoBS) - 2014 3 | http://github.com/nothings/stb 4 | 5 | Written with emphasis on usability, portability, and efficiency. (No 6 | SIMD or threads, so it be easily outperformed by libs that use those.) 7 | Only scaling and translation is supported, no rotations or shears. 8 | Easy API downsamples w/Mitchell filter, upsamples w/cubic interpolation. 9 | 10 | COMPILING & LINKING 11 | In one C/C++ file that #includes this file, do this: 12 | #define STB_IMAGE_RESIZE_IMPLEMENTATION 13 | before the #include. That will create the implementation in that file. 14 | 15 | QUICKSTART 16 | stbir_resize_uint8( input_pixels , in_w , in_h , 0, 17 | output_pixels, out_w, out_h, 0, num_channels) 18 | stbir_resize_float(...) 19 | stbir_resize_uint8_srgb( input_pixels , in_w , in_h , 0, 20 | output_pixels, out_w, out_h, 0, 21 | num_channels , alpha_chan , 0) 22 | stbir_resize_uint8_srgb_edgemode( 23 | input_pixels , in_w , in_h , 0, 24 | output_pixels, out_w, out_h, 0, 25 | num_channels , alpha_chan , 0, STBIR_EDGE_CLAMP) 26 | // WRAP/REFLECT/ZERO 27 | 28 | FULL API 29 | See the "header file" section of the source for API documentation. 30 | 31 | ADDITIONAL DOCUMENTATION 32 | 33 | SRGB & FLOATING POINT REPRESENTATION 34 | The sRGB functions presume IEEE floating point. If you do not have 35 | IEEE floating point, define STBIR_NON_IEEE_FLOAT. This will use 36 | a slower implementation. 37 | 38 | MEMORY ALLOCATION 39 | The resize functions here perform a single memory allocation using 40 | malloc. To control the memory allocation, before the #include that 41 | triggers the implementation, do: 42 | 43 | #define STBIR_MALLOC(size,context) ... 44 | #define STBIR_FREE(ptr,context) ... 45 | 46 | Each resize function makes exactly one call to malloc/free, so to use 47 | temp memory, store the temp memory in the context and return that. 48 | 49 | ASSERT 50 | Define STBIR_ASSERT(boolval) to override assert() and not use assert.h 51 | 52 | OPTIMIZATION 53 | Define STBIR_SATURATE_INT to compute clamp values in-range using 54 | integer operations instead of float operations. This may be faster 55 | on some platforms. 56 | 57 | DEFAULT FILTERS 58 | For functions which don't provide explicit control over what filters 59 | to use, you can change the compile-time defaults with 60 | 61 | #define STBIR_DEFAULT_FILTER_UPSAMPLE STBIR_FILTER_something 62 | #define STBIR_DEFAULT_FILTER_DOWNSAMPLE STBIR_FILTER_something 63 | 64 | See stbir_filter in the header-file section for the list of filters. 65 | 66 | NEW FILTERS 67 | A number of 1D filter kernels are used. For a list of 68 | supported filters see the stbir_filter enum. To add a new filter, 69 | write a filter function and add it to stbir__filter_info_table. 70 | 71 | PROGRESS 72 | For interactive use with slow resize operations, you can install 73 | a progress-report callback: 74 | 75 | #define STBIR_PROGRESS_REPORT(val) some_func(val) 76 | 77 | The parameter val is a float which goes from 0 to 1 as progress is made. 78 | 79 | For example: 80 | 81 | static void my_progress_report(float progress); 82 | #define STBIR_PROGRESS_REPORT(val) my_progress_report(val) 83 | 84 | #define STB_IMAGE_RESIZE_IMPLEMENTATION 85 | #include "stb_image_resize.h" 86 | 87 | static void my_progress_report(float progress) 88 | { 89 | printf("Progress: %f%%\n", progress*100); 90 | } 91 | 92 | MAX CHANNELS 93 | If your image has more than 64 channels, define STBIR_MAX_CHANNELS 94 | to the max you'll have. 95 | 96 | ALPHA CHANNEL 97 | Most of the resizing functions provide the ability to control how 98 | the alpha channel of an image is processed. The important things 99 | to know about this: 100 | 101 | 1. The best mathematically-behaved version of alpha to use is 102 | called "premultiplied alpha", in which the other color channels 103 | have had the alpha value multiplied in. If you use premultiplied 104 | alpha, linear filtering (such as image resampling done by this 105 | library, or performed in texture units on GPUs) does the "right 106 | thing". While premultiplied alpha is standard in the movie CGI 107 | industry, it is still uncommon in the videogame/real-time world. 108 | 109 | If you linearly filter non-premultiplied alpha, strange effects 110 | occur. (For example, the 50/50 average of 99% transparent bright green 111 | and 1% transparent black produces 50% transparent dark green when 112 | non-premultiplied, whereas premultiplied it produces 50% 113 | transparent near-black. The former introduces green energy 114 | that doesn't exist in the source image.) 115 | 116 | 2. Artists should not edit premultiplied-alpha images; artists 117 | want non-premultiplied alpha images. Thus, art tools generally output 118 | non-premultiplied alpha images. 119 | 120 | 3. You will get best results in most cases by converting images 121 | to premultiplied alpha before processing them mathematically. 122 | 123 | 4. If you pass the flag STBIR_FLAG_ALPHA_PREMULTIPLIED, the 124 | resizer does not do anything special for the alpha channel; 125 | it is resampled identically to other channels. This produces 126 | the correct results for premultiplied-alpha images, but produces 127 | less-than-ideal results for non-premultiplied-alpha images. 128 | 129 | 5. If you do not pass the flag STBIR_FLAG_ALPHA_PREMULTIPLIED, 130 | then the resizer weights the contribution of input pixels 131 | based on their alpha values, or, equivalently, it multiplies 132 | the alpha value into the color channels, resamples, then divides 133 | by the resultant alpha value. Input pixels which have alpha=0 do 134 | not contribute at all to output pixels unless _all_ of the input 135 | pixels affecting that output pixel have alpha=0, in which case 136 | the result for that pixel is the same as it would be without 137 | STBIR_FLAG_ALPHA_PREMULTIPLIED. However, this is only true for 138 | input images in integer formats. For input images in float format, 139 | input pixels with alpha=0 have no effect, and output pixels 140 | which have alpha=0 will be 0 in all channels. (For float images, 141 | you can manually achieve the same result by adding a tiny epsilon 142 | value to the alpha channel of every image, and then subtracting 143 | or clamping it at the end.) 144 | 145 | 6. You can suppress the behavior described in #5 and make 146 | all-0-alpha pixels have 0 in all channels by #defining 147 | STBIR_NO_ALPHA_EPSILON. 148 | 149 | 7. You can separately control whether the alpha channel is 150 | interpreted as linear or affected by the colorspace. By default 151 | it is linear; you almost never want to apply the colorspace. 152 | (For example, graphics hardware does not apply sRGB conversion 153 | to the alpha channel.) 154 | 155 | CONTRIBUTORS 156 | Jorge L Rodriguez: Implementation 157 | Sean Barrett: API design, optimizations 158 | Aras Pranckevicius: bugfix 159 | Nathan Reed: warning fixes 160 | 161 | REVISIONS 162 | 0.97 (2020-02-02) fixed warning 163 | 0.96 (2019-03-04) fixed warnings 164 | 0.95 (2017-07-23) fixed warnings 165 | 0.94 (2017-03-18) fixed warnings 166 | 0.93 (2017-03-03) fixed bug with certain combinations of heights 167 | 0.92 (2017-01-02) fix integer overflow on large (>2GB) images 168 | 0.91 (2016-04-02) fix warnings; fix handling of subpixel regions 169 | 0.90 (2014-09-17) first released version 170 | 171 | LICENSE 172 | See end of file for license information. 173 | 174 | TODO 175 | Don't decode all of the image data when only processing a partial tile 176 | Don't use full-width decode buffers when only processing a partial tile 177 | When processing wide images, break processing into tiles so data fits in L1 cache 178 | Installable filters? 179 | Resize that respects alpha test coverage 180 | (Reference code: FloatImage::alphaTestCoverage and FloatImage::scaleAlphaToCoverage: 181 | https://code.google.com/p/nvidia-texture-tools/source/browse/trunk/src/nvimage/FloatImage.cpp ) 182 | */ 183 | 184 | #ifndef STBIR_INCLUDE_STB_IMAGE_RESIZE_H 185 | #define STBIR_INCLUDE_STB_IMAGE_RESIZE_H 186 | 187 | #ifdef _MSC_VER 188 | typedef unsigned char stbir_uint8; 189 | typedef unsigned short stbir_uint16; 190 | typedef unsigned int stbir_uint32; 191 | #else 192 | #include 193 | typedef uint8_t stbir_uint8; 194 | typedef uint16_t stbir_uint16; 195 | typedef uint32_t stbir_uint32; 196 | #endif 197 | 198 | #ifndef STBIRDEF 199 | #ifdef STB_IMAGE_RESIZE_STATIC 200 | #define STBIRDEF static 201 | #else 202 | #ifdef __cplusplus 203 | #define STBIRDEF extern "C" 204 | #else 205 | #define STBIRDEF extern 206 | #endif 207 | #endif 208 | #endif 209 | 210 | ////////////////////////////////////////////////////////////////////////////// 211 | // 212 | // Easy-to-use API: 213 | // 214 | // * "input pixels" points to an array of image data with 'num_channels' channels (e.g. RGB=3, RGBA=4) 215 | // * input_w is input image width (x-axis), input_h is input image height (y-axis) 216 | // * stride is the offset between successive rows of image data in memory, in bytes. you can 217 | // specify 0 to mean packed continuously in memory 218 | // * alpha channel is treated identically to other channels. 219 | // * colorspace is linear or sRGB as specified by function name 220 | // * returned result is 1 for success or 0 in case of an error. 221 | // #define STBIR_ASSERT() to trigger an assert on parameter validation errors. 222 | // * Memory required grows approximately linearly with input and output size, but with 223 | // discontinuities at input_w == output_w and input_h == output_h. 224 | // * These functions use a "default" resampling filter defined at compile time. To change the filter, 225 | // you can change the compile-time defaults by #defining STBIR_DEFAULT_FILTER_UPSAMPLE 226 | // and STBIR_DEFAULT_FILTER_DOWNSAMPLE, or you can use the medium-complexity API. 227 | 228 | STBIRDEF int stbir_resize_uint8( const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 229 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 230 | int num_channels); 231 | 232 | STBIRDEF int stbir_resize_float( const float *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 233 | float *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 234 | int num_channels); 235 | 236 | 237 | // The following functions interpret image data as gamma-corrected sRGB. 238 | // Specify STBIR_ALPHA_CHANNEL_NONE if you have no alpha channel, 239 | // or otherwise provide the index of the alpha channel. Flags value 240 | // of 0 will probably do the right thing if you're not sure what 241 | // the flags mean. 242 | 243 | #define STBIR_ALPHA_CHANNEL_NONE -1 244 | 245 | // Set this flag if your texture has premultiplied alpha. Otherwise, stbir will 246 | // use alpha-weighted resampling (effectively premultiplying, resampling, 247 | // then unpremultiplying). 248 | #define STBIR_FLAG_ALPHA_PREMULTIPLIED (1 << 0) 249 | // The specified alpha channel should be handled as gamma-corrected value even 250 | // when doing sRGB operations. 251 | #define STBIR_FLAG_ALPHA_USES_COLORSPACE (1 << 1) 252 | 253 | STBIRDEF int stbir_resize_uint8_srgb(const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 254 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 255 | int num_channels, int alpha_channel, int flags); 256 | 257 | 258 | typedef enum 259 | { 260 | STBIR_EDGE_CLAMP = 1, 261 | STBIR_EDGE_REFLECT = 2, 262 | STBIR_EDGE_WRAP = 3, 263 | STBIR_EDGE_ZERO = 4, 264 | } stbir_edge; 265 | 266 | // This function adds the ability to specify how requests to sample off the edge of the image are handled. 267 | STBIRDEF int stbir_resize_uint8_srgb_edgemode(const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 268 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 269 | int num_channels, int alpha_channel, int flags, 270 | stbir_edge edge_wrap_mode); 271 | 272 | ////////////////////////////////////////////////////////////////////////////// 273 | // 274 | // Medium-complexity API 275 | // 276 | // This extends the easy-to-use API as follows: 277 | // 278 | // * Alpha-channel can be processed separately 279 | // * If alpha_channel is not STBIR_ALPHA_CHANNEL_NONE 280 | // * Alpha channel will not be gamma corrected (unless flags&STBIR_FLAG_GAMMA_CORRECT) 281 | // * Filters will be weighted by alpha channel (unless flags&STBIR_FLAG_ALPHA_PREMULTIPLIED) 282 | // * Filter can be selected explicitly 283 | // * uint16 image type 284 | // * sRGB colorspace available for all types 285 | // * context parameter for passing to STBIR_MALLOC 286 | 287 | typedef enum 288 | { 289 | STBIR_FILTER_DEFAULT = 0, // use same filter type that easy-to-use API chooses 290 | STBIR_FILTER_BOX = 1, // A trapezoid w/1-pixel wide ramps, same result as box for integer scale ratios 291 | STBIR_FILTER_TRIANGLE = 2, // On upsampling, produces same results as bilinear texture filtering 292 | STBIR_FILTER_CUBICBSPLINE = 3, // The cubic b-spline (aka Mitchell-Netrevalli with B=1,C=0), gaussian-esque 293 | STBIR_FILTER_CATMULLROM = 4, // An interpolating cubic spline 294 | STBIR_FILTER_MITCHELL = 5, // Mitchell-Netrevalli filter with B=1/3, C=1/3 295 | } stbir_filter; 296 | 297 | typedef enum 298 | { 299 | STBIR_COLORSPACE_LINEAR, 300 | STBIR_COLORSPACE_SRGB, 301 | 302 | STBIR_MAX_COLORSPACES, 303 | } stbir_colorspace; 304 | 305 | // The following functions are all identical except for the type of the image data 306 | 307 | STBIRDEF int stbir_resize_uint8_generic( const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 308 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 309 | int num_channels, int alpha_channel, int flags, 310 | stbir_edge edge_wrap_mode, stbir_filter filter, stbir_colorspace space, 311 | void *alloc_context); 312 | 313 | STBIRDEF int stbir_resize_uint16_generic(const stbir_uint16 *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 314 | stbir_uint16 *output_pixels , int output_w, int output_h, int output_stride_in_bytes, 315 | int num_channels, int alpha_channel, int flags, 316 | stbir_edge edge_wrap_mode, stbir_filter filter, stbir_colorspace space, 317 | void *alloc_context); 318 | 319 | STBIRDEF int stbir_resize_float_generic( const float *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 320 | float *output_pixels , int output_w, int output_h, int output_stride_in_bytes, 321 | int num_channels, int alpha_channel, int flags, 322 | stbir_edge edge_wrap_mode, stbir_filter filter, stbir_colorspace space, 323 | void *alloc_context); 324 | 325 | 326 | 327 | ////////////////////////////////////////////////////////////////////////////// 328 | // 329 | // Full-complexity API 330 | // 331 | // This extends the medium API as follows: 332 | // 333 | // * uint32 image type 334 | // * not typesafe 335 | // * separate filter types for each axis 336 | // * separate edge modes for each axis 337 | // * can specify scale explicitly for subpixel correctness 338 | // * can specify image source tile using texture coordinates 339 | 340 | typedef enum 341 | { 342 | STBIR_TYPE_UINT8 , 343 | STBIR_TYPE_UINT16, 344 | STBIR_TYPE_UINT32, 345 | STBIR_TYPE_FLOAT , 346 | 347 | STBIR_MAX_TYPES 348 | } stbir_datatype; 349 | 350 | STBIRDEF int stbir_resize( const void *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 351 | void *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 352 | stbir_datatype datatype, 353 | int num_channels, int alpha_channel, int flags, 354 | stbir_edge edge_mode_horizontal, stbir_edge edge_mode_vertical, 355 | stbir_filter filter_horizontal, stbir_filter filter_vertical, 356 | stbir_colorspace space, void *alloc_context); 357 | 358 | STBIRDEF int stbir_resize_subpixel(const void *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 359 | void *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 360 | stbir_datatype datatype, 361 | int num_channels, int alpha_channel, int flags, 362 | stbir_edge edge_mode_horizontal, stbir_edge edge_mode_vertical, 363 | stbir_filter filter_horizontal, stbir_filter filter_vertical, 364 | stbir_colorspace space, void *alloc_context, 365 | float x_scale, float y_scale, 366 | float x_offset, float y_offset); 367 | 368 | STBIRDEF int stbir_resize_region( const void *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 369 | void *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 370 | stbir_datatype datatype, 371 | int num_channels, int alpha_channel, int flags, 372 | stbir_edge edge_mode_horizontal, stbir_edge edge_mode_vertical, 373 | stbir_filter filter_horizontal, stbir_filter filter_vertical, 374 | stbir_colorspace space, void *alloc_context, 375 | float s0, float t0, float s1, float t1); 376 | // (s0, t0) & (s1, t1) are the top-left and bottom right corner (uv addressing style: [0, 1]x[0, 1]) of a region of the input image to use. 377 | 378 | // 379 | // 380 | //// end header file ///////////////////////////////////////////////////// 381 | #endif // STBIR_INCLUDE_STB_IMAGE_RESIZE_H 382 | 383 | 384 | 385 | 386 | 387 | #ifdef STB_IMAGE_RESIZE_IMPLEMENTATION 388 | 389 | #ifndef STBIR_ASSERT 390 | #include 391 | #define STBIR_ASSERT(x) assert(x) 392 | #endif 393 | 394 | // For memset 395 | #include 396 | 397 | #include 398 | 399 | #ifndef STBIR_MALLOC 400 | #include 401 | // use comma operator to evaluate c, to avoid "unused parameter" warnings 402 | #define STBIR_MALLOC(size,c) ((void)(c), malloc(size)) 403 | #define STBIR_FREE(ptr,c) ((void)(c), free(ptr)) 404 | #endif 405 | 406 | #ifndef _MSC_VER 407 | #ifdef __cplusplus 408 | #define stbir__inline inline 409 | #else 410 | #define stbir__inline 411 | #endif 412 | #else 413 | #define stbir__inline __forceinline 414 | #endif 415 | 416 | 417 | // should produce compiler error if size is wrong 418 | typedef unsigned char stbir__validate_uint32[sizeof(stbir_uint32) == 4 ? 1 : -1]; 419 | 420 | #ifdef _MSC_VER 421 | #define STBIR__NOTUSED(v) (void)(v) 422 | #else 423 | #define STBIR__NOTUSED(v) (void)sizeof(v) 424 | #endif 425 | 426 | #define STBIR__ARRAY_SIZE(a) (sizeof((a))/sizeof((a)[0])) 427 | 428 | #ifndef STBIR_DEFAULT_FILTER_UPSAMPLE 429 | #define STBIR_DEFAULT_FILTER_UPSAMPLE STBIR_FILTER_CATMULLROM 430 | #endif 431 | 432 | #ifndef STBIR_DEFAULT_FILTER_DOWNSAMPLE 433 | #define STBIR_DEFAULT_FILTER_DOWNSAMPLE STBIR_FILTER_MITCHELL 434 | #endif 435 | 436 | #ifndef STBIR_PROGRESS_REPORT 437 | #define STBIR_PROGRESS_REPORT(float_0_to_1) 438 | #endif 439 | 440 | #ifndef STBIR_MAX_CHANNELS 441 | #define STBIR_MAX_CHANNELS 64 442 | #endif 443 | 444 | #if STBIR_MAX_CHANNELS > 65536 445 | #error "Too many channels; STBIR_MAX_CHANNELS must be no more than 65536." 446 | // because we store the indices in 16-bit variables 447 | #endif 448 | 449 | // This value is added to alpha just before premultiplication to avoid 450 | // zeroing out color values. It is equivalent to 2^-80. If you don't want 451 | // that behavior (it may interfere if you have floating point images with 452 | // very small alpha values) then you can define STBIR_NO_ALPHA_EPSILON to 453 | // disable it. 454 | #ifndef STBIR_ALPHA_EPSILON 455 | #define STBIR_ALPHA_EPSILON ((float)1 / (1 << 20) / (1 << 20) / (1 << 20) / (1 << 20)) 456 | #endif 457 | 458 | 459 | 460 | #ifdef _MSC_VER 461 | #define STBIR__UNUSED_PARAM(v) (void)(v) 462 | #else 463 | #define STBIR__UNUSED_PARAM(v) (void)sizeof(v) 464 | #endif 465 | 466 | // must match stbir_datatype 467 | static unsigned char stbir__type_size[] = { 468 | 1, // STBIR_TYPE_UINT8 469 | 2, // STBIR_TYPE_UINT16 470 | 4, // STBIR_TYPE_UINT32 471 | 4, // STBIR_TYPE_FLOAT 472 | }; 473 | 474 | // Kernel function centered at 0 475 | typedef float (stbir__kernel_fn)(float x, float scale); 476 | typedef float (stbir__support_fn)(float scale); 477 | 478 | typedef struct 479 | { 480 | stbir__kernel_fn* kernel; 481 | stbir__support_fn* support; 482 | } stbir__filter_info; 483 | 484 | // When upsampling, the contributors are which source pixels contribute. 485 | // When downsampling, the contributors are which destination pixels are contributed to. 486 | typedef struct 487 | { 488 | int n0; // First contributing pixel 489 | int n1; // Last contributing pixel 490 | } stbir__contributors; 491 | 492 | typedef struct 493 | { 494 | const void* input_data; 495 | int input_w; 496 | int input_h; 497 | int input_stride_bytes; 498 | 499 | void* output_data; 500 | int output_w; 501 | int output_h; 502 | int output_stride_bytes; 503 | 504 | float s0, t0, s1, t1; 505 | 506 | float horizontal_shift; // Units: output pixels 507 | float vertical_shift; // Units: output pixels 508 | float horizontal_scale; 509 | float vertical_scale; 510 | 511 | int channels; 512 | int alpha_channel; 513 | stbir_uint32 flags; 514 | stbir_datatype type; 515 | stbir_filter horizontal_filter; 516 | stbir_filter vertical_filter; 517 | stbir_edge edge_horizontal; 518 | stbir_edge edge_vertical; 519 | stbir_colorspace colorspace; 520 | 521 | stbir__contributors* horizontal_contributors; 522 | float* horizontal_coefficients; 523 | 524 | stbir__contributors* vertical_contributors; 525 | float* vertical_coefficients; 526 | 527 | int decode_buffer_pixels; 528 | float* decode_buffer; 529 | 530 | float* horizontal_buffer; 531 | 532 | // cache these because ceil/floor are inexplicably showing up in profile 533 | int horizontal_coefficient_width; 534 | int vertical_coefficient_width; 535 | int horizontal_filter_pixel_width; 536 | int vertical_filter_pixel_width; 537 | int horizontal_filter_pixel_margin; 538 | int vertical_filter_pixel_margin; 539 | int horizontal_num_contributors; 540 | int vertical_num_contributors; 541 | 542 | int ring_buffer_length_bytes; // The length of an individual entry in the ring buffer. The total number of ring buffers is stbir__get_filter_pixel_width(filter) 543 | int ring_buffer_num_entries; // Total number of entries in the ring buffer. 544 | int ring_buffer_first_scanline; 545 | int ring_buffer_last_scanline; 546 | int ring_buffer_begin_index; // first_scanline is at this index in the ring buffer 547 | float* ring_buffer; 548 | 549 | float* encode_buffer; // A temporary buffer to store floats so we don't lose precision while we do multiply-adds. 550 | 551 | int horizontal_contributors_size; 552 | int horizontal_coefficients_size; 553 | int vertical_contributors_size; 554 | int vertical_coefficients_size; 555 | int decode_buffer_size; 556 | int horizontal_buffer_size; 557 | int ring_buffer_size; 558 | int encode_buffer_size; 559 | } stbir__info; 560 | 561 | 562 | static const float stbir__max_uint8_as_float = 255.0f; 563 | static const float stbir__max_uint16_as_float = 65535.0f; 564 | static const double stbir__max_uint32_as_float = 4294967295.0; 565 | 566 | 567 | static stbir__inline int stbir__min(int a, int b) 568 | { 569 | return a < b ? a : b; 570 | } 571 | 572 | static stbir__inline float stbir__saturate(float x) 573 | { 574 | if (x < 0) 575 | return 0; 576 | 577 | if (x > 1) 578 | return 1; 579 | 580 | return x; 581 | } 582 | 583 | #ifdef STBIR_SATURATE_INT 584 | static stbir__inline stbir_uint8 stbir__saturate8(int x) 585 | { 586 | if ((unsigned int) x <= 255) 587 | return x; 588 | 589 | if (x < 0) 590 | return 0; 591 | 592 | return 255; 593 | } 594 | 595 | static stbir__inline stbir_uint16 stbir__saturate16(int x) 596 | { 597 | if ((unsigned int) x <= 65535) 598 | return x; 599 | 600 | if (x < 0) 601 | return 0; 602 | 603 | return 65535; 604 | } 605 | #endif 606 | 607 | static float stbir__srgb_uchar_to_linear_float[256] = { 608 | 0.000000f, 0.000304f, 0.000607f, 0.000911f, 0.001214f, 0.001518f, 0.001821f, 0.002125f, 0.002428f, 0.002732f, 0.003035f, 609 | 0.003347f, 0.003677f, 0.004025f, 0.004391f, 0.004777f, 0.005182f, 0.005605f, 0.006049f, 0.006512f, 0.006995f, 0.007499f, 610 | 0.008023f, 0.008568f, 0.009134f, 0.009721f, 0.010330f, 0.010960f, 0.011612f, 0.012286f, 0.012983f, 0.013702f, 0.014444f, 611 | 0.015209f, 0.015996f, 0.016807f, 0.017642f, 0.018500f, 0.019382f, 0.020289f, 0.021219f, 0.022174f, 0.023153f, 0.024158f, 612 | 0.025187f, 0.026241f, 0.027321f, 0.028426f, 0.029557f, 0.030713f, 0.031896f, 0.033105f, 0.034340f, 0.035601f, 0.036889f, 613 | 0.038204f, 0.039546f, 0.040915f, 0.042311f, 0.043735f, 0.045186f, 0.046665f, 0.048172f, 0.049707f, 0.051269f, 0.052861f, 614 | 0.054480f, 0.056128f, 0.057805f, 0.059511f, 0.061246f, 0.063010f, 0.064803f, 0.066626f, 0.068478f, 0.070360f, 0.072272f, 615 | 0.074214f, 0.076185f, 0.078187f, 0.080220f, 0.082283f, 0.084376f, 0.086500f, 0.088656f, 0.090842f, 0.093059f, 0.095307f, 616 | 0.097587f, 0.099899f, 0.102242f, 0.104616f, 0.107023f, 0.109462f, 0.111932f, 0.114435f, 0.116971f, 0.119538f, 0.122139f, 617 | 0.124772f, 0.127438f, 0.130136f, 0.132868f, 0.135633f, 0.138432f, 0.141263f, 0.144128f, 0.147027f, 0.149960f, 0.152926f, 618 | 0.155926f, 0.158961f, 0.162029f, 0.165132f, 0.168269f, 0.171441f, 0.174647f, 0.177888f, 0.181164f, 0.184475f, 0.187821f, 619 | 0.191202f, 0.194618f, 0.198069f, 0.201556f, 0.205079f, 0.208637f, 0.212231f, 0.215861f, 0.219526f, 0.223228f, 0.226966f, 620 | 0.230740f, 0.234551f, 0.238398f, 0.242281f, 0.246201f, 0.250158f, 0.254152f, 0.258183f, 0.262251f, 0.266356f, 0.270498f, 621 | 0.274677f, 0.278894f, 0.283149f, 0.287441f, 0.291771f, 0.296138f, 0.300544f, 0.304987f, 0.309469f, 0.313989f, 0.318547f, 622 | 0.323143f, 0.327778f, 0.332452f, 0.337164f, 0.341914f, 0.346704f, 0.351533f, 0.356400f, 0.361307f, 0.366253f, 0.371238f, 623 | 0.376262f, 0.381326f, 0.386430f, 0.391573f, 0.396755f, 0.401978f, 0.407240f, 0.412543f, 0.417885f, 0.423268f, 0.428691f, 624 | 0.434154f, 0.439657f, 0.445201f, 0.450786f, 0.456411f, 0.462077f, 0.467784f, 0.473532f, 0.479320f, 0.485150f, 0.491021f, 625 | 0.496933f, 0.502887f, 0.508881f, 0.514918f, 0.520996f, 0.527115f, 0.533276f, 0.539480f, 0.545725f, 0.552011f, 0.558340f, 626 | 0.564712f, 0.571125f, 0.577581f, 0.584078f, 0.590619f, 0.597202f, 0.603827f, 0.610496f, 0.617207f, 0.623960f, 0.630757f, 627 | 0.637597f, 0.644480f, 0.651406f, 0.658375f, 0.665387f, 0.672443f, 0.679543f, 0.686685f, 0.693872f, 0.701102f, 0.708376f, 628 | 0.715694f, 0.723055f, 0.730461f, 0.737911f, 0.745404f, 0.752942f, 0.760525f, 0.768151f, 0.775822f, 0.783538f, 0.791298f, 629 | 0.799103f, 0.806952f, 0.814847f, 0.822786f, 0.830770f, 0.838799f, 0.846873f, 0.854993f, 0.863157f, 0.871367f, 0.879622f, 630 | 0.887923f, 0.896269f, 0.904661f, 0.913099f, 0.921582f, 0.930111f, 0.938686f, 0.947307f, 0.955974f, 0.964686f, 0.973445f, 631 | 0.982251f, 0.991102f, 1.0f 632 | }; 633 | 634 | static float stbir__srgb_to_linear(float f) 635 | { 636 | if (f <= 0.04045f) 637 | return f / 12.92f; 638 | else 639 | return (float)pow((f + 0.055f) / 1.055f, 2.4f); 640 | } 641 | 642 | static float stbir__linear_to_srgb(float f) 643 | { 644 | if (f <= 0.0031308f) 645 | return f * 12.92f; 646 | else 647 | return 1.055f * (float)pow(f, 1 / 2.4f) - 0.055f; 648 | } 649 | 650 | #ifndef STBIR_NON_IEEE_FLOAT 651 | // From https://gist.github.com/rygorous/2203834 652 | 653 | typedef union 654 | { 655 | stbir_uint32 u; 656 | float f; 657 | } stbir__FP32; 658 | 659 | static const stbir_uint32 fp32_to_srgb8_tab4[104] = { 660 | 0x0073000d, 0x007a000d, 0x0080000d, 0x0087000d, 0x008d000d, 0x0094000d, 0x009a000d, 0x00a1000d, 661 | 0x00a7001a, 0x00b4001a, 0x00c1001a, 0x00ce001a, 0x00da001a, 0x00e7001a, 0x00f4001a, 0x0101001a, 662 | 0x010e0033, 0x01280033, 0x01410033, 0x015b0033, 0x01750033, 0x018f0033, 0x01a80033, 0x01c20033, 663 | 0x01dc0067, 0x020f0067, 0x02430067, 0x02760067, 0x02aa0067, 0x02dd0067, 0x03110067, 0x03440067, 664 | 0x037800ce, 0x03df00ce, 0x044600ce, 0x04ad00ce, 0x051400ce, 0x057b00c5, 0x05dd00bc, 0x063b00b5, 665 | 0x06970158, 0x07420142, 0x07e30130, 0x087b0120, 0x090b0112, 0x09940106, 0x0a1700fc, 0x0a9500f2, 666 | 0x0b0f01cb, 0x0bf401ae, 0x0ccb0195, 0x0d950180, 0x0e56016e, 0x0f0d015e, 0x0fbc0150, 0x10630143, 667 | 0x11070264, 0x1238023e, 0x1357021d, 0x14660201, 0x156601e9, 0x165a01d3, 0x174401c0, 0x182401af, 668 | 0x18fe0331, 0x1a9602fe, 0x1c1502d2, 0x1d7e02ad, 0x1ed4028d, 0x201a0270, 0x21520256, 0x227d0240, 669 | 0x239f0443, 0x25c003fe, 0x27bf03c4, 0x29a10392, 0x2b6a0367, 0x2d1d0341, 0x2ebe031f, 0x304d0300, 670 | 0x31d105b0, 0x34a80555, 0x37520507, 0x39d504c5, 0x3c37048b, 0x3e7c0458, 0x40a8042a, 0x42bd0401, 671 | 0x44c20798, 0x488e071e, 0x4c1c06b6, 0x4f76065d, 0x52a50610, 0x55ac05cc, 0x5892058f, 0x5b590559, 672 | 0x5e0c0a23, 0x631c0980, 0x67db08f6, 0x6c55087f, 0x70940818, 0x74a007bd, 0x787d076c, 0x7c330723, 673 | }; 674 | 675 | static stbir_uint8 stbir__linear_to_srgb_uchar(float in) 676 | { 677 | static const stbir__FP32 almostone = { 0x3f7fffff }; // 1-eps 678 | static const stbir__FP32 minval = { (127-13) << 23 }; 679 | stbir_uint32 tab,bias,scale,t; 680 | stbir__FP32 f; 681 | 682 | // Clamp to [2^(-13), 1-eps]; these two values map to 0 and 1, respectively. 683 | // The tests are carefully written so that NaNs map to 0, same as in the reference 684 | // implementation. 685 | if (!(in > minval.f)) // written this way to catch NaNs 686 | in = minval.f; 687 | if (in > almostone.f) 688 | in = almostone.f; 689 | 690 | // Do the table lookup and unpack bias, scale 691 | f.f = in; 692 | tab = fp32_to_srgb8_tab4[(f.u - minval.u) >> 20]; 693 | bias = (tab >> 16) << 9; 694 | scale = tab & 0xffff; 695 | 696 | // Grab next-highest mantissa bits and perform linear interpolation 697 | t = (f.u >> 12) & 0xff; 698 | return (unsigned char) ((bias + scale*t) >> 16); 699 | } 700 | 701 | #else 702 | // sRGB transition values, scaled by 1<<28 703 | static int stbir__srgb_offset_to_linear_scaled[256] = 704 | { 705 | 0, 40738, 122216, 203693, 285170, 366648, 448125, 529603, 706 | 611080, 692557, 774035, 855852, 942009, 1033024, 1128971, 1229926, 707 | 1335959, 1447142, 1563542, 1685229, 1812268, 1944725, 2082664, 2226148, 708 | 2375238, 2529996, 2690481, 2856753, 3028870, 3206888, 3390865, 3580856, 709 | 3776916, 3979100, 4187460, 4402049, 4622919, 4850123, 5083710, 5323731, 710 | 5570236, 5823273, 6082892, 6349140, 6622065, 6901714, 7188133, 7481369, 711 | 7781466, 8088471, 8402427, 8723380, 9051372, 9386448, 9728650, 10078021, 712 | 10434603, 10798439, 11169569, 11548036, 11933879, 12327139, 12727857, 13136073, 713 | 13551826, 13975156, 14406100, 14844697, 15290987, 15745007, 16206795, 16676389, 714 | 17153826, 17639142, 18132374, 18633560, 19142734, 19659934, 20185196, 20718552, 715 | 21260042, 21809696, 22367554, 22933648, 23508010, 24090680, 24681686, 25281066, 716 | 25888850, 26505076, 27129772, 27762974, 28404716, 29055026, 29713942, 30381490, 717 | 31057708, 31742624, 32436272, 33138682, 33849884, 34569912, 35298800, 36036568, 718 | 36783260, 37538896, 38303512, 39077136, 39859796, 40651528, 41452360, 42262316, 719 | 43081432, 43909732, 44747252, 45594016, 46450052, 47315392, 48190064, 49074096, 720 | 49967516, 50870356, 51782636, 52704392, 53635648, 54576432, 55526772, 56486700, 721 | 57456236, 58435408, 59424248, 60422780, 61431036, 62449032, 63476804, 64514376, 722 | 65561776, 66619028, 67686160, 68763192, 69850160, 70947088, 72053992, 73170912, 723 | 74297864, 75434880, 76581976, 77739184, 78906536, 80084040, 81271736, 82469648, 724 | 83677792, 84896192, 86124888, 87363888, 88613232, 89872928, 91143016, 92423512, 725 | 93714432, 95015816, 96327688, 97650056, 98982952, 100326408, 101680440, 103045072, 726 | 104420320, 105806224, 107202800, 108610064, 110028048, 111456776, 112896264, 114346544, 727 | 115807632, 117279552, 118762328, 120255976, 121760536, 123276016, 124802440, 126339832, 728 | 127888216, 129447616, 131018048, 132599544, 134192112, 135795792, 137410592, 139036528, 729 | 140673648, 142321952, 143981456, 145652208, 147334208, 149027488, 150732064, 152447968, 730 | 154175200, 155913792, 157663776, 159425168, 161197984, 162982240, 164777968, 166585184, 731 | 168403904, 170234160, 172075968, 173929344, 175794320, 177670896, 179559120, 181458992, 732 | 183370528, 185293776, 187228736, 189175424, 191133888, 193104112, 195086128, 197079968, 733 | 199085648, 201103184, 203132592, 205173888, 207227120, 209292272, 211369392, 213458480, 734 | 215559568, 217672656, 219797792, 221934976, 224084240, 226245600, 228419056, 230604656, 735 | 232802400, 235012320, 237234432, 239468736, 241715280, 243974080, 246245120, 248528464, 736 | 250824112, 253132064, 255452368, 257785040, 260130080, 262487520, 264857376, 267239664, 737 | }; 738 | 739 | static stbir_uint8 stbir__linear_to_srgb_uchar(float f) 740 | { 741 | int x = (int) (f * (1 << 28)); // has headroom so you don't need to clamp 742 | int v = 0; 743 | int i; 744 | 745 | // Refine the guess with a short binary search. 746 | i = v + 128; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 747 | i = v + 64; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 748 | i = v + 32; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 749 | i = v + 16; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 750 | i = v + 8; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 751 | i = v + 4; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 752 | i = v + 2; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 753 | i = v + 1; if (x >= stbir__srgb_offset_to_linear_scaled[i]) v = i; 754 | 755 | return (stbir_uint8) v; 756 | } 757 | #endif 758 | 759 | static float stbir__filter_trapezoid(float x, float scale) 760 | { 761 | float halfscale = scale / 2; 762 | float t = 0.5f + halfscale; 763 | STBIR_ASSERT(scale <= 1); 764 | 765 | x = (float)fabs(x); 766 | 767 | if (x >= t) 768 | return 0; 769 | else 770 | { 771 | float r = 0.5f - halfscale; 772 | if (x <= r) 773 | return 1; 774 | else 775 | return (t - x) / scale; 776 | } 777 | } 778 | 779 | static float stbir__support_trapezoid(float scale) 780 | { 781 | STBIR_ASSERT(scale <= 1); 782 | return 0.5f + scale / 2; 783 | } 784 | 785 | static float stbir__filter_triangle(float x, float s) 786 | { 787 | STBIR__UNUSED_PARAM(s); 788 | 789 | x = (float)fabs(x); 790 | 791 | if (x <= 1.0f) 792 | return 1 - x; 793 | else 794 | return 0; 795 | } 796 | 797 | static float stbir__filter_cubic(float x, float s) 798 | { 799 | STBIR__UNUSED_PARAM(s); 800 | 801 | x = (float)fabs(x); 802 | 803 | if (x < 1.0f) 804 | return (4 + x*x*(3*x - 6))/6; 805 | else if (x < 2.0f) 806 | return (8 + x*(-12 + x*(6 - x)))/6; 807 | 808 | return (0.0f); 809 | } 810 | 811 | static float stbir__filter_catmullrom(float x, float s) 812 | { 813 | STBIR__UNUSED_PARAM(s); 814 | 815 | x = (float)fabs(x); 816 | 817 | if (x < 1.0f) 818 | return 1 - x*x*(2.5f - 1.5f*x); 819 | else if (x < 2.0f) 820 | return 2 - x*(4 + x*(0.5f*x - 2.5f)); 821 | 822 | return (0.0f); 823 | } 824 | 825 | static float stbir__filter_mitchell(float x, float s) 826 | { 827 | STBIR__UNUSED_PARAM(s); 828 | 829 | x = (float)fabs(x); 830 | 831 | if (x < 1.0f) 832 | return (16 + x*x*(21 * x - 36))/18; 833 | else if (x < 2.0f) 834 | return (32 + x*(-60 + x*(36 - 7*x)))/18; 835 | 836 | return (0.0f); 837 | } 838 | 839 | static float stbir__support_zero(float s) 840 | { 841 | STBIR__UNUSED_PARAM(s); 842 | return 0; 843 | } 844 | 845 | static float stbir__support_one(float s) 846 | { 847 | STBIR__UNUSED_PARAM(s); 848 | return 1; 849 | } 850 | 851 | static float stbir__support_two(float s) 852 | { 853 | STBIR__UNUSED_PARAM(s); 854 | return 2; 855 | } 856 | 857 | static stbir__filter_info stbir__filter_info_table[] = { 858 | { NULL, stbir__support_zero }, 859 | { stbir__filter_trapezoid, stbir__support_trapezoid }, 860 | { stbir__filter_triangle, stbir__support_one }, 861 | { stbir__filter_cubic, stbir__support_two }, 862 | { stbir__filter_catmullrom, stbir__support_two }, 863 | { stbir__filter_mitchell, stbir__support_two }, 864 | }; 865 | 866 | stbir__inline static int stbir__use_upsampling(float ratio) 867 | { 868 | return ratio > 1; 869 | } 870 | 871 | stbir__inline static int stbir__use_width_upsampling(stbir__info* stbir_info) 872 | { 873 | return stbir__use_upsampling(stbir_info->horizontal_scale); 874 | } 875 | 876 | stbir__inline static int stbir__use_height_upsampling(stbir__info* stbir_info) 877 | { 878 | return stbir__use_upsampling(stbir_info->vertical_scale); 879 | } 880 | 881 | // This is the maximum number of input samples that can affect an output sample 882 | // with the given filter 883 | static int stbir__get_filter_pixel_width(stbir_filter filter, float scale) 884 | { 885 | STBIR_ASSERT(filter != 0); 886 | STBIR_ASSERT(filter < STBIR__ARRAY_SIZE(stbir__filter_info_table)); 887 | 888 | if (stbir__use_upsampling(scale)) 889 | return (int)ceil(stbir__filter_info_table[filter].support(1/scale) * 2); 890 | else 891 | return (int)ceil(stbir__filter_info_table[filter].support(scale) * 2 / scale); 892 | } 893 | 894 | // This is how much to expand buffers to account for filters seeking outside 895 | // the image boundaries. 896 | static int stbir__get_filter_pixel_margin(stbir_filter filter, float scale) 897 | { 898 | return stbir__get_filter_pixel_width(filter, scale) / 2; 899 | } 900 | 901 | static int stbir__get_coefficient_width(stbir_filter filter, float scale) 902 | { 903 | if (stbir__use_upsampling(scale)) 904 | return (int)ceil(stbir__filter_info_table[filter].support(1 / scale) * 2); 905 | else 906 | return (int)ceil(stbir__filter_info_table[filter].support(scale) * 2); 907 | } 908 | 909 | static int stbir__get_contributors(float scale, stbir_filter filter, int input_size, int output_size) 910 | { 911 | if (stbir__use_upsampling(scale)) 912 | return output_size; 913 | else 914 | return (input_size + stbir__get_filter_pixel_margin(filter, scale) * 2); 915 | } 916 | 917 | static int stbir__get_total_horizontal_coefficients(stbir__info* info) 918 | { 919 | return info->horizontal_num_contributors 920 | * stbir__get_coefficient_width (info->horizontal_filter, info->horizontal_scale); 921 | } 922 | 923 | static int stbir__get_total_vertical_coefficients(stbir__info* info) 924 | { 925 | return info->vertical_num_contributors 926 | * stbir__get_coefficient_width (info->vertical_filter, info->vertical_scale); 927 | } 928 | 929 | static stbir__contributors* stbir__get_contributor(stbir__contributors* contributors, int n) 930 | { 931 | return &contributors[n]; 932 | } 933 | 934 | // For perf reasons this code is duplicated in stbir__resample_horizontal_upsample/downsample, 935 | // if you change it here change it there too. 936 | static float* stbir__get_coefficient(float* coefficients, stbir_filter filter, float scale, int n, int c) 937 | { 938 | int width = stbir__get_coefficient_width(filter, scale); 939 | return &coefficients[width*n + c]; 940 | } 941 | 942 | static int stbir__edge_wrap_slow(stbir_edge edge, int n, int max) 943 | { 944 | switch (edge) 945 | { 946 | case STBIR_EDGE_ZERO: 947 | return 0; // we'll decode the wrong pixel here, and then overwrite with 0s later 948 | 949 | case STBIR_EDGE_CLAMP: 950 | if (n < 0) 951 | return 0; 952 | 953 | if (n >= max) 954 | return max - 1; 955 | 956 | return n; // NOTREACHED 957 | 958 | case STBIR_EDGE_REFLECT: 959 | { 960 | if (n < 0) 961 | { 962 | if (n < max) 963 | return -n; 964 | else 965 | return max - 1; 966 | } 967 | 968 | if (n >= max) 969 | { 970 | int max2 = max * 2; 971 | if (n >= max2) 972 | return 0; 973 | else 974 | return max2 - n - 1; 975 | } 976 | 977 | return n; // NOTREACHED 978 | } 979 | 980 | case STBIR_EDGE_WRAP: 981 | if (n >= 0) 982 | return (n % max); 983 | else 984 | { 985 | int m = (-n) % max; 986 | 987 | if (m != 0) 988 | m = max - m; 989 | 990 | return (m); 991 | } 992 | // NOTREACHED 993 | 994 | default: 995 | STBIR_ASSERT(!"Unimplemented edge type"); 996 | return 0; 997 | } 998 | } 999 | 1000 | stbir__inline static int stbir__edge_wrap(stbir_edge edge, int n, int max) 1001 | { 1002 | // avoid per-pixel switch 1003 | if (n >= 0 && n < max) 1004 | return n; 1005 | return stbir__edge_wrap_slow(edge, n, max); 1006 | } 1007 | 1008 | // What input pixels contribute to this output pixel? 1009 | static void stbir__calculate_sample_range_upsample(int n, float out_filter_radius, float scale_ratio, float out_shift, int* in_first_pixel, int* in_last_pixel, float* in_center_of_out) 1010 | { 1011 | float out_pixel_center = (float)n + 0.5f; 1012 | float out_pixel_influence_lowerbound = out_pixel_center - out_filter_radius; 1013 | float out_pixel_influence_upperbound = out_pixel_center + out_filter_radius; 1014 | 1015 | float in_pixel_influence_lowerbound = (out_pixel_influence_lowerbound + out_shift) / scale_ratio; 1016 | float in_pixel_influence_upperbound = (out_pixel_influence_upperbound + out_shift) / scale_ratio; 1017 | 1018 | *in_center_of_out = (out_pixel_center + out_shift) / scale_ratio; 1019 | *in_first_pixel = (int)(floor(in_pixel_influence_lowerbound + 0.5)); 1020 | *in_last_pixel = (int)(floor(in_pixel_influence_upperbound - 0.5)); 1021 | } 1022 | 1023 | // What output pixels does this input pixel contribute to? 1024 | static void stbir__calculate_sample_range_downsample(int n, float in_pixels_radius, float scale_ratio, float out_shift, int* out_first_pixel, int* out_last_pixel, float* out_center_of_in) 1025 | { 1026 | float in_pixel_center = (float)n + 0.5f; 1027 | float in_pixel_influence_lowerbound = in_pixel_center - in_pixels_radius; 1028 | float in_pixel_influence_upperbound = in_pixel_center + in_pixels_radius; 1029 | 1030 | float out_pixel_influence_lowerbound = in_pixel_influence_lowerbound * scale_ratio - out_shift; 1031 | float out_pixel_influence_upperbound = in_pixel_influence_upperbound * scale_ratio - out_shift; 1032 | 1033 | *out_center_of_in = in_pixel_center * scale_ratio - out_shift; 1034 | *out_first_pixel = (int)(floor(out_pixel_influence_lowerbound + 0.5)); 1035 | *out_last_pixel = (int)(floor(out_pixel_influence_upperbound - 0.5)); 1036 | } 1037 | 1038 | static void stbir__calculate_coefficients_upsample(stbir_filter filter, float scale, int in_first_pixel, int in_last_pixel, float in_center_of_out, stbir__contributors* contributor, float* coefficient_group) 1039 | { 1040 | int i; 1041 | float total_filter = 0; 1042 | float filter_scale; 1043 | 1044 | STBIR_ASSERT(in_last_pixel - in_first_pixel <= (int)ceil(stbir__filter_info_table[filter].support(1/scale) * 2)); // Taken directly from stbir__get_coefficient_width() which we can't call because we don't know if we're horizontal or vertical. 1045 | 1046 | contributor->n0 = in_first_pixel; 1047 | contributor->n1 = in_last_pixel; 1048 | 1049 | STBIR_ASSERT(contributor->n1 >= contributor->n0); 1050 | 1051 | for (i = 0; i <= in_last_pixel - in_first_pixel; i++) 1052 | { 1053 | float in_pixel_center = (float)(i + in_first_pixel) + 0.5f; 1054 | coefficient_group[i] = stbir__filter_info_table[filter].kernel(in_center_of_out - in_pixel_center, 1 / scale); 1055 | 1056 | // If the coefficient is zero, skip it. (Don't do the <0 check here, we want the influence of those outside pixels.) 1057 | if (i == 0 && !coefficient_group[i]) 1058 | { 1059 | contributor->n0 = ++in_first_pixel; 1060 | i--; 1061 | continue; 1062 | } 1063 | 1064 | total_filter += coefficient_group[i]; 1065 | } 1066 | 1067 | // NOTE(fg): Not actually true in general, nor is there any reason to expect it should be. 1068 | // It would be true in exact math but is at best approximately true in floating-point math, 1069 | // and it would not make sense to try and put actual bounds on this here because it depends 1070 | // on the image aspect ratio which can get pretty extreme. 1071 | //STBIR_ASSERT(stbir__filter_info_table[filter].kernel((float)(in_last_pixel + 1) + 0.5f - in_center_of_out, 1/scale) == 0); 1072 | 1073 | STBIR_ASSERT(total_filter > 0.9); 1074 | STBIR_ASSERT(total_filter < 1.1f); // Make sure it's not way off. 1075 | 1076 | // Make sure the sum of all coefficients is 1. 1077 | filter_scale = 1 / total_filter; 1078 | 1079 | for (i = 0; i <= in_last_pixel - in_first_pixel; i++) 1080 | coefficient_group[i] *= filter_scale; 1081 | 1082 | for (i = in_last_pixel - in_first_pixel; i >= 0; i--) 1083 | { 1084 | if (coefficient_group[i]) 1085 | break; 1086 | 1087 | // This line has no weight. We can skip it. 1088 | contributor->n1 = contributor->n0 + i - 1; 1089 | } 1090 | } 1091 | 1092 | static void stbir__calculate_coefficients_downsample(stbir_filter filter, float scale_ratio, int out_first_pixel, int out_last_pixel, float out_center_of_in, stbir__contributors* contributor, float* coefficient_group) 1093 | { 1094 | int i; 1095 | 1096 | STBIR_ASSERT(out_last_pixel - out_first_pixel <= (int)ceil(stbir__filter_info_table[filter].support(scale_ratio) * 2)); // Taken directly from stbir__get_coefficient_width() which we can't call because we don't know if we're horizontal or vertical. 1097 | 1098 | contributor->n0 = out_first_pixel; 1099 | contributor->n1 = out_last_pixel; 1100 | 1101 | STBIR_ASSERT(contributor->n1 >= contributor->n0); 1102 | 1103 | for (i = 0; i <= out_last_pixel - out_first_pixel; i++) 1104 | { 1105 | float out_pixel_center = (float)(i + out_first_pixel) + 0.5f; 1106 | float x = out_pixel_center - out_center_of_in; 1107 | coefficient_group[i] = stbir__filter_info_table[filter].kernel(x, scale_ratio) * scale_ratio; 1108 | } 1109 | 1110 | // NOTE(fg): Not actually true in general, nor is there any reason to expect it should be. 1111 | // It would be true in exact math but is at best approximately true in floating-point math, 1112 | // and it would not make sense to try and put actual bounds on this here because it depends 1113 | // on the image aspect ratio which can get pretty extreme. 1114 | //STBIR_ASSERT(stbir__filter_info_table[filter].kernel((float)(out_last_pixel + 1) + 0.5f - out_center_of_in, scale_ratio) == 0); 1115 | 1116 | for (i = out_last_pixel - out_first_pixel; i >= 0; i--) 1117 | { 1118 | if (coefficient_group[i]) 1119 | break; 1120 | 1121 | // This line has no weight. We can skip it. 1122 | contributor->n1 = contributor->n0 + i - 1; 1123 | } 1124 | } 1125 | 1126 | static void stbir__normalize_downsample_coefficients(stbir__contributors* contributors, float* coefficients, stbir_filter filter, float scale_ratio, int input_size, int output_size) 1127 | { 1128 | int num_contributors = stbir__get_contributors(scale_ratio, filter, input_size, output_size); 1129 | int num_coefficients = stbir__get_coefficient_width(filter, scale_ratio); 1130 | int i, j; 1131 | int skip; 1132 | 1133 | for (i = 0; i < output_size; i++) 1134 | { 1135 | float scale; 1136 | float total = 0; 1137 | 1138 | for (j = 0; j < num_contributors; j++) 1139 | { 1140 | if (i >= contributors[j].n0 && i <= contributors[j].n1) 1141 | { 1142 | float coefficient = *stbir__get_coefficient(coefficients, filter, scale_ratio, j, i - contributors[j].n0); 1143 | total += coefficient; 1144 | } 1145 | else if (i < contributors[j].n0) 1146 | break; 1147 | } 1148 | 1149 | STBIR_ASSERT(total > 0.9f); 1150 | STBIR_ASSERT(total < 1.1f); 1151 | 1152 | scale = 1 / total; 1153 | 1154 | for (j = 0; j < num_contributors; j++) 1155 | { 1156 | if (i >= contributors[j].n0 && i <= contributors[j].n1) 1157 | *stbir__get_coefficient(coefficients, filter, scale_ratio, j, i - contributors[j].n0) *= scale; 1158 | else if (i < contributors[j].n0) 1159 | break; 1160 | } 1161 | } 1162 | 1163 | // Optimize: Skip zero coefficients and contributions outside of image bounds. 1164 | // Do this after normalizing because normalization depends on the n0/n1 values. 1165 | for (j = 0; j < num_contributors; j++) 1166 | { 1167 | int range, max, width; 1168 | 1169 | skip = 0; 1170 | while (*stbir__get_coefficient(coefficients, filter, scale_ratio, j, skip) == 0) 1171 | skip++; 1172 | 1173 | contributors[j].n0 += skip; 1174 | 1175 | while (contributors[j].n0 < 0) 1176 | { 1177 | contributors[j].n0++; 1178 | skip++; 1179 | } 1180 | 1181 | range = contributors[j].n1 - contributors[j].n0 + 1; 1182 | max = stbir__min(num_coefficients, range); 1183 | 1184 | width = stbir__get_coefficient_width(filter, scale_ratio); 1185 | for (i = 0; i < max; i++) 1186 | { 1187 | if (i + skip >= width) 1188 | break; 1189 | 1190 | *stbir__get_coefficient(coefficients, filter, scale_ratio, j, i) = *stbir__get_coefficient(coefficients, filter, scale_ratio, j, i + skip); 1191 | } 1192 | 1193 | continue; 1194 | } 1195 | 1196 | // Using min to avoid writing into invalid pixels. 1197 | for (i = 0; i < num_contributors; i++) 1198 | contributors[i].n1 = stbir__min(contributors[i].n1, output_size - 1); 1199 | } 1200 | 1201 | // Each scan line uses the same kernel values so we should calculate the kernel 1202 | // values once and then we can use them for every scan line. 1203 | static void stbir__calculate_filters(stbir__contributors* contributors, float* coefficients, stbir_filter filter, float scale_ratio, float shift, int input_size, int output_size) 1204 | { 1205 | int n; 1206 | int total_contributors = stbir__get_contributors(scale_ratio, filter, input_size, output_size); 1207 | 1208 | if (stbir__use_upsampling(scale_ratio)) 1209 | { 1210 | float out_pixels_radius = stbir__filter_info_table[filter].support(1 / scale_ratio) * scale_ratio; 1211 | 1212 | // Looping through out pixels 1213 | for (n = 0; n < total_contributors; n++) 1214 | { 1215 | float in_center_of_out; // Center of the current out pixel in the in pixel space 1216 | int in_first_pixel, in_last_pixel; 1217 | 1218 | stbir__calculate_sample_range_upsample(n, out_pixels_radius, scale_ratio, shift, &in_first_pixel, &in_last_pixel, &in_center_of_out); 1219 | 1220 | stbir__calculate_coefficients_upsample(filter, scale_ratio, in_first_pixel, in_last_pixel, in_center_of_out, stbir__get_contributor(contributors, n), stbir__get_coefficient(coefficients, filter, scale_ratio, n, 0)); 1221 | } 1222 | } 1223 | else 1224 | { 1225 | float in_pixels_radius = stbir__filter_info_table[filter].support(scale_ratio) / scale_ratio; 1226 | 1227 | // Looping through in pixels 1228 | for (n = 0; n < total_contributors; n++) 1229 | { 1230 | float out_center_of_in; // Center of the current out pixel in the in pixel space 1231 | int out_first_pixel, out_last_pixel; 1232 | int n_adjusted = n - stbir__get_filter_pixel_margin(filter, scale_ratio); 1233 | 1234 | stbir__calculate_sample_range_downsample(n_adjusted, in_pixels_radius, scale_ratio, shift, &out_first_pixel, &out_last_pixel, &out_center_of_in); 1235 | 1236 | stbir__calculate_coefficients_downsample(filter, scale_ratio, out_first_pixel, out_last_pixel, out_center_of_in, stbir__get_contributor(contributors, n), stbir__get_coefficient(coefficients, filter, scale_ratio, n, 0)); 1237 | } 1238 | 1239 | stbir__normalize_downsample_coefficients(contributors, coefficients, filter, scale_ratio, input_size, output_size); 1240 | } 1241 | } 1242 | 1243 | static float* stbir__get_decode_buffer(stbir__info* stbir_info) 1244 | { 1245 | // The 0 index of the decode buffer starts after the margin. This makes 1246 | // it okay to use negative indexes on the decode buffer. 1247 | return &stbir_info->decode_buffer[stbir_info->horizontal_filter_pixel_margin * stbir_info->channels]; 1248 | } 1249 | 1250 | #define STBIR__DECODE(type, colorspace) ((int)(type) * (STBIR_MAX_COLORSPACES) + (int)(colorspace)) 1251 | 1252 | static void stbir__decode_scanline(stbir__info* stbir_info, int n) 1253 | { 1254 | int c; 1255 | int channels = stbir_info->channels; 1256 | int alpha_channel = stbir_info->alpha_channel; 1257 | int type = stbir_info->type; 1258 | int colorspace = stbir_info->colorspace; 1259 | int input_w = stbir_info->input_w; 1260 | size_t input_stride_bytes = stbir_info->input_stride_bytes; 1261 | float* decode_buffer = stbir__get_decode_buffer(stbir_info); 1262 | stbir_edge edge_horizontal = stbir_info->edge_horizontal; 1263 | stbir_edge edge_vertical = stbir_info->edge_vertical; 1264 | size_t in_buffer_row_offset = stbir__edge_wrap(edge_vertical, n, stbir_info->input_h) * input_stride_bytes; 1265 | const void* input_data = (char *) stbir_info->input_data + in_buffer_row_offset; 1266 | int max_x = input_w + stbir_info->horizontal_filter_pixel_margin; 1267 | int decode = STBIR__DECODE(type, colorspace); 1268 | 1269 | int x = -stbir_info->horizontal_filter_pixel_margin; 1270 | 1271 | // special handling for STBIR_EDGE_ZERO because it needs to return an item that doesn't appear in the input, 1272 | // and we want to avoid paying overhead on every pixel if not STBIR_EDGE_ZERO 1273 | if (edge_vertical == STBIR_EDGE_ZERO && (n < 0 || n >= stbir_info->input_h)) 1274 | { 1275 | for (; x < max_x; x++) 1276 | for (c = 0; c < channels; c++) 1277 | decode_buffer[x*channels + c] = 0; 1278 | return; 1279 | } 1280 | 1281 | switch (decode) 1282 | { 1283 | case STBIR__DECODE(STBIR_TYPE_UINT8, STBIR_COLORSPACE_LINEAR): 1284 | for (; x < max_x; x++) 1285 | { 1286 | int decode_pixel_index = x * channels; 1287 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1288 | for (c = 0; c < channels; c++) 1289 | decode_buffer[decode_pixel_index + c] = ((float)((const unsigned char*)input_data)[input_pixel_index + c]) / stbir__max_uint8_as_float; 1290 | } 1291 | break; 1292 | 1293 | case STBIR__DECODE(STBIR_TYPE_UINT8, STBIR_COLORSPACE_SRGB): 1294 | for (; x < max_x; x++) 1295 | { 1296 | int decode_pixel_index = x * channels; 1297 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1298 | for (c = 0; c < channels; c++) 1299 | decode_buffer[decode_pixel_index + c] = stbir__srgb_uchar_to_linear_float[((const unsigned char*)input_data)[input_pixel_index + c]]; 1300 | 1301 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1302 | decode_buffer[decode_pixel_index + alpha_channel] = ((float)((const unsigned char*)input_data)[input_pixel_index + alpha_channel]) / stbir__max_uint8_as_float; 1303 | } 1304 | break; 1305 | 1306 | case STBIR__DECODE(STBIR_TYPE_UINT16, STBIR_COLORSPACE_LINEAR): 1307 | for (; x < max_x; x++) 1308 | { 1309 | int decode_pixel_index = x * channels; 1310 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1311 | for (c = 0; c < channels; c++) 1312 | decode_buffer[decode_pixel_index + c] = ((float)((const unsigned short*)input_data)[input_pixel_index + c]) / stbir__max_uint16_as_float; 1313 | } 1314 | break; 1315 | 1316 | case STBIR__DECODE(STBIR_TYPE_UINT16, STBIR_COLORSPACE_SRGB): 1317 | for (; x < max_x; x++) 1318 | { 1319 | int decode_pixel_index = x * channels; 1320 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1321 | for (c = 0; c < channels; c++) 1322 | decode_buffer[decode_pixel_index + c] = stbir__srgb_to_linear(((float)((const unsigned short*)input_data)[input_pixel_index + c]) / stbir__max_uint16_as_float); 1323 | 1324 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1325 | decode_buffer[decode_pixel_index + alpha_channel] = ((float)((const unsigned short*)input_data)[input_pixel_index + alpha_channel]) / stbir__max_uint16_as_float; 1326 | } 1327 | break; 1328 | 1329 | case STBIR__DECODE(STBIR_TYPE_UINT32, STBIR_COLORSPACE_LINEAR): 1330 | for (; x < max_x; x++) 1331 | { 1332 | int decode_pixel_index = x * channels; 1333 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1334 | for (c = 0; c < channels; c++) 1335 | decode_buffer[decode_pixel_index + c] = (float)(((double)((const unsigned int*)input_data)[input_pixel_index + c]) / stbir__max_uint32_as_float); 1336 | } 1337 | break; 1338 | 1339 | case STBIR__DECODE(STBIR_TYPE_UINT32, STBIR_COLORSPACE_SRGB): 1340 | for (; x < max_x; x++) 1341 | { 1342 | int decode_pixel_index = x * channels; 1343 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1344 | for (c = 0; c < channels; c++) 1345 | decode_buffer[decode_pixel_index + c] = stbir__srgb_to_linear((float)(((double)((const unsigned int*)input_data)[input_pixel_index + c]) / stbir__max_uint32_as_float)); 1346 | 1347 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1348 | decode_buffer[decode_pixel_index + alpha_channel] = (float)(((double)((const unsigned int*)input_data)[input_pixel_index + alpha_channel]) / stbir__max_uint32_as_float); 1349 | } 1350 | break; 1351 | 1352 | case STBIR__DECODE(STBIR_TYPE_FLOAT, STBIR_COLORSPACE_LINEAR): 1353 | for (; x < max_x; x++) 1354 | { 1355 | int decode_pixel_index = x * channels; 1356 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1357 | for (c = 0; c < channels; c++) 1358 | decode_buffer[decode_pixel_index + c] = ((const float*)input_data)[input_pixel_index + c]; 1359 | } 1360 | break; 1361 | 1362 | case STBIR__DECODE(STBIR_TYPE_FLOAT, STBIR_COLORSPACE_SRGB): 1363 | for (; x < max_x; x++) 1364 | { 1365 | int decode_pixel_index = x * channels; 1366 | int input_pixel_index = stbir__edge_wrap(edge_horizontal, x, input_w) * channels; 1367 | for (c = 0; c < channels; c++) 1368 | decode_buffer[decode_pixel_index + c] = stbir__srgb_to_linear(((const float*)input_data)[input_pixel_index + c]); 1369 | 1370 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1371 | decode_buffer[decode_pixel_index + alpha_channel] = ((const float*)input_data)[input_pixel_index + alpha_channel]; 1372 | } 1373 | 1374 | break; 1375 | 1376 | default: 1377 | STBIR_ASSERT(!"Unknown type/colorspace/channels combination."); 1378 | break; 1379 | } 1380 | 1381 | if (!(stbir_info->flags & STBIR_FLAG_ALPHA_PREMULTIPLIED)) 1382 | { 1383 | for (x = -stbir_info->horizontal_filter_pixel_margin; x < max_x; x++) 1384 | { 1385 | int decode_pixel_index = x * channels; 1386 | 1387 | // If the alpha value is 0 it will clobber the color values. Make sure it's not. 1388 | float alpha = decode_buffer[decode_pixel_index + alpha_channel]; 1389 | #ifndef STBIR_NO_ALPHA_EPSILON 1390 | if (stbir_info->type != STBIR_TYPE_FLOAT) { 1391 | alpha += STBIR_ALPHA_EPSILON; 1392 | decode_buffer[decode_pixel_index + alpha_channel] = alpha; 1393 | } 1394 | #endif 1395 | for (c = 0; c < channels; c++) 1396 | { 1397 | if (c == alpha_channel) 1398 | continue; 1399 | 1400 | decode_buffer[decode_pixel_index + c] *= alpha; 1401 | } 1402 | } 1403 | } 1404 | 1405 | if (edge_horizontal == STBIR_EDGE_ZERO) 1406 | { 1407 | for (x = -stbir_info->horizontal_filter_pixel_margin; x < 0; x++) 1408 | { 1409 | for (c = 0; c < channels; c++) 1410 | decode_buffer[x*channels + c] = 0; 1411 | } 1412 | for (x = input_w; x < max_x; x++) 1413 | { 1414 | for (c = 0; c < channels; c++) 1415 | decode_buffer[x*channels + c] = 0; 1416 | } 1417 | } 1418 | } 1419 | 1420 | static float* stbir__get_ring_buffer_entry(float* ring_buffer, int index, int ring_buffer_length) 1421 | { 1422 | return &ring_buffer[index * ring_buffer_length]; 1423 | } 1424 | 1425 | static float* stbir__add_empty_ring_buffer_entry(stbir__info* stbir_info, int n) 1426 | { 1427 | int ring_buffer_index; 1428 | float* ring_buffer; 1429 | 1430 | stbir_info->ring_buffer_last_scanline = n; 1431 | 1432 | if (stbir_info->ring_buffer_begin_index < 0) 1433 | { 1434 | ring_buffer_index = stbir_info->ring_buffer_begin_index = 0; 1435 | stbir_info->ring_buffer_first_scanline = n; 1436 | } 1437 | else 1438 | { 1439 | ring_buffer_index = (stbir_info->ring_buffer_begin_index + (stbir_info->ring_buffer_last_scanline - stbir_info->ring_buffer_first_scanline)) % stbir_info->ring_buffer_num_entries; 1440 | STBIR_ASSERT(ring_buffer_index != stbir_info->ring_buffer_begin_index); 1441 | } 1442 | 1443 | ring_buffer = stbir__get_ring_buffer_entry(stbir_info->ring_buffer, ring_buffer_index, stbir_info->ring_buffer_length_bytes / sizeof(float)); 1444 | memset(ring_buffer, 0, stbir_info->ring_buffer_length_bytes); 1445 | 1446 | return ring_buffer; 1447 | } 1448 | 1449 | 1450 | static void stbir__resample_horizontal_upsample(stbir__info* stbir_info, float* output_buffer) 1451 | { 1452 | int x, k; 1453 | int output_w = stbir_info->output_w; 1454 | int channels = stbir_info->channels; 1455 | float* decode_buffer = stbir__get_decode_buffer(stbir_info); 1456 | stbir__contributors* horizontal_contributors = stbir_info->horizontal_contributors; 1457 | float* horizontal_coefficients = stbir_info->horizontal_coefficients; 1458 | int coefficient_width = stbir_info->horizontal_coefficient_width; 1459 | 1460 | for (x = 0; x < output_w; x++) 1461 | { 1462 | int n0 = horizontal_contributors[x].n0; 1463 | int n1 = horizontal_contributors[x].n1; 1464 | 1465 | int out_pixel_index = x * channels; 1466 | int coefficient_group = coefficient_width * x; 1467 | int coefficient_counter = 0; 1468 | 1469 | STBIR_ASSERT(n1 >= n0); 1470 | STBIR_ASSERT(n0 >= -stbir_info->horizontal_filter_pixel_margin); 1471 | STBIR_ASSERT(n1 >= -stbir_info->horizontal_filter_pixel_margin); 1472 | STBIR_ASSERT(n0 < stbir_info->input_w + stbir_info->horizontal_filter_pixel_margin); 1473 | STBIR_ASSERT(n1 < stbir_info->input_w + stbir_info->horizontal_filter_pixel_margin); 1474 | 1475 | switch (channels) { 1476 | case 1: 1477 | for (k = n0; k <= n1; k++) 1478 | { 1479 | int in_pixel_index = k * 1; 1480 | float coefficient = horizontal_coefficients[coefficient_group + coefficient_counter++]; 1481 | STBIR_ASSERT(coefficient != 0); 1482 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1483 | } 1484 | break; 1485 | case 2: 1486 | for (k = n0; k <= n1; k++) 1487 | { 1488 | int in_pixel_index = k * 2; 1489 | float coefficient = horizontal_coefficients[coefficient_group + coefficient_counter++]; 1490 | STBIR_ASSERT(coefficient != 0); 1491 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1492 | output_buffer[out_pixel_index + 1] += decode_buffer[in_pixel_index + 1] * coefficient; 1493 | } 1494 | break; 1495 | case 3: 1496 | for (k = n0; k <= n1; k++) 1497 | { 1498 | int in_pixel_index = k * 3; 1499 | float coefficient = horizontal_coefficients[coefficient_group + coefficient_counter++]; 1500 | STBIR_ASSERT(coefficient != 0); 1501 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1502 | output_buffer[out_pixel_index + 1] += decode_buffer[in_pixel_index + 1] * coefficient; 1503 | output_buffer[out_pixel_index + 2] += decode_buffer[in_pixel_index + 2] * coefficient; 1504 | } 1505 | break; 1506 | case 4: 1507 | for (k = n0; k <= n1; k++) 1508 | { 1509 | int in_pixel_index = k * 4; 1510 | float coefficient = horizontal_coefficients[coefficient_group + coefficient_counter++]; 1511 | STBIR_ASSERT(coefficient != 0); 1512 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1513 | output_buffer[out_pixel_index + 1] += decode_buffer[in_pixel_index + 1] * coefficient; 1514 | output_buffer[out_pixel_index + 2] += decode_buffer[in_pixel_index + 2] * coefficient; 1515 | output_buffer[out_pixel_index + 3] += decode_buffer[in_pixel_index + 3] * coefficient; 1516 | } 1517 | break; 1518 | default: 1519 | for (k = n0; k <= n1; k++) 1520 | { 1521 | int in_pixel_index = k * channels; 1522 | float coefficient = horizontal_coefficients[coefficient_group + coefficient_counter++]; 1523 | int c; 1524 | STBIR_ASSERT(coefficient != 0); 1525 | for (c = 0; c < channels; c++) 1526 | output_buffer[out_pixel_index + c] += decode_buffer[in_pixel_index + c] * coefficient; 1527 | } 1528 | break; 1529 | } 1530 | } 1531 | } 1532 | 1533 | static void stbir__resample_horizontal_downsample(stbir__info* stbir_info, float* output_buffer) 1534 | { 1535 | int x, k; 1536 | int input_w = stbir_info->input_w; 1537 | int channels = stbir_info->channels; 1538 | float* decode_buffer = stbir__get_decode_buffer(stbir_info); 1539 | stbir__contributors* horizontal_contributors = stbir_info->horizontal_contributors; 1540 | float* horizontal_coefficients = stbir_info->horizontal_coefficients; 1541 | int coefficient_width = stbir_info->horizontal_coefficient_width; 1542 | int filter_pixel_margin = stbir_info->horizontal_filter_pixel_margin; 1543 | int max_x = input_w + filter_pixel_margin * 2; 1544 | 1545 | STBIR_ASSERT(!stbir__use_width_upsampling(stbir_info)); 1546 | 1547 | switch (channels) { 1548 | case 1: 1549 | for (x = 0; x < max_x; x++) 1550 | { 1551 | int n0 = horizontal_contributors[x].n0; 1552 | int n1 = horizontal_contributors[x].n1; 1553 | 1554 | int in_x = x - filter_pixel_margin; 1555 | int in_pixel_index = in_x * 1; 1556 | int max_n = n1; 1557 | int coefficient_group = coefficient_width * x; 1558 | 1559 | for (k = n0; k <= max_n; k++) 1560 | { 1561 | int out_pixel_index = k * 1; 1562 | float coefficient = horizontal_coefficients[coefficient_group + k - n0]; 1563 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1564 | } 1565 | } 1566 | break; 1567 | 1568 | case 2: 1569 | for (x = 0; x < max_x; x++) 1570 | { 1571 | int n0 = horizontal_contributors[x].n0; 1572 | int n1 = horizontal_contributors[x].n1; 1573 | 1574 | int in_x = x - filter_pixel_margin; 1575 | int in_pixel_index = in_x * 2; 1576 | int max_n = n1; 1577 | int coefficient_group = coefficient_width * x; 1578 | 1579 | for (k = n0; k <= max_n; k++) 1580 | { 1581 | int out_pixel_index = k * 2; 1582 | float coefficient = horizontal_coefficients[coefficient_group + k - n0]; 1583 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1584 | output_buffer[out_pixel_index + 1] += decode_buffer[in_pixel_index + 1] * coefficient; 1585 | } 1586 | } 1587 | break; 1588 | 1589 | case 3: 1590 | for (x = 0; x < max_x; x++) 1591 | { 1592 | int n0 = horizontal_contributors[x].n0; 1593 | int n1 = horizontal_contributors[x].n1; 1594 | 1595 | int in_x = x - filter_pixel_margin; 1596 | int in_pixel_index = in_x * 3; 1597 | int max_n = n1; 1598 | int coefficient_group = coefficient_width * x; 1599 | 1600 | for (k = n0; k <= max_n; k++) 1601 | { 1602 | int out_pixel_index = k * 3; 1603 | float coefficient = horizontal_coefficients[coefficient_group + k - n0]; 1604 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1605 | output_buffer[out_pixel_index + 1] += decode_buffer[in_pixel_index + 1] * coefficient; 1606 | output_buffer[out_pixel_index + 2] += decode_buffer[in_pixel_index + 2] * coefficient; 1607 | } 1608 | } 1609 | break; 1610 | 1611 | case 4: 1612 | for (x = 0; x < max_x; x++) 1613 | { 1614 | int n0 = horizontal_contributors[x].n0; 1615 | int n1 = horizontal_contributors[x].n1; 1616 | 1617 | int in_x = x - filter_pixel_margin; 1618 | int in_pixel_index = in_x * 4; 1619 | int max_n = n1; 1620 | int coefficient_group = coefficient_width * x; 1621 | 1622 | for (k = n0; k <= max_n; k++) 1623 | { 1624 | int out_pixel_index = k * 4; 1625 | float coefficient = horizontal_coefficients[coefficient_group + k - n0]; 1626 | output_buffer[out_pixel_index + 0] += decode_buffer[in_pixel_index + 0] * coefficient; 1627 | output_buffer[out_pixel_index + 1] += decode_buffer[in_pixel_index + 1] * coefficient; 1628 | output_buffer[out_pixel_index + 2] += decode_buffer[in_pixel_index + 2] * coefficient; 1629 | output_buffer[out_pixel_index + 3] += decode_buffer[in_pixel_index + 3] * coefficient; 1630 | } 1631 | } 1632 | break; 1633 | 1634 | default: 1635 | for (x = 0; x < max_x; x++) 1636 | { 1637 | int n0 = horizontal_contributors[x].n0; 1638 | int n1 = horizontal_contributors[x].n1; 1639 | 1640 | int in_x = x - filter_pixel_margin; 1641 | int in_pixel_index = in_x * channels; 1642 | int max_n = n1; 1643 | int coefficient_group = coefficient_width * x; 1644 | 1645 | for (k = n0; k <= max_n; k++) 1646 | { 1647 | int c; 1648 | int out_pixel_index = k * channels; 1649 | float coefficient = horizontal_coefficients[coefficient_group + k - n0]; 1650 | for (c = 0; c < channels; c++) 1651 | output_buffer[out_pixel_index + c] += decode_buffer[in_pixel_index + c] * coefficient; 1652 | } 1653 | } 1654 | break; 1655 | } 1656 | } 1657 | 1658 | static void stbir__decode_and_resample_upsample(stbir__info* stbir_info, int n) 1659 | { 1660 | // Decode the nth scanline from the source image into the decode buffer. 1661 | stbir__decode_scanline(stbir_info, n); 1662 | 1663 | // Now resample it into the ring buffer. 1664 | if (stbir__use_width_upsampling(stbir_info)) 1665 | stbir__resample_horizontal_upsample(stbir_info, stbir__add_empty_ring_buffer_entry(stbir_info, n)); 1666 | else 1667 | stbir__resample_horizontal_downsample(stbir_info, stbir__add_empty_ring_buffer_entry(stbir_info, n)); 1668 | 1669 | // Now it's sitting in the ring buffer ready to be used as source for the vertical sampling. 1670 | } 1671 | 1672 | static void stbir__decode_and_resample_downsample(stbir__info* stbir_info, int n) 1673 | { 1674 | // Decode the nth scanline from the source image into the decode buffer. 1675 | stbir__decode_scanline(stbir_info, n); 1676 | 1677 | memset(stbir_info->horizontal_buffer, 0, stbir_info->output_w * stbir_info->channels * sizeof(float)); 1678 | 1679 | // Now resample it into the horizontal buffer. 1680 | if (stbir__use_width_upsampling(stbir_info)) 1681 | stbir__resample_horizontal_upsample(stbir_info, stbir_info->horizontal_buffer); 1682 | else 1683 | stbir__resample_horizontal_downsample(stbir_info, stbir_info->horizontal_buffer); 1684 | 1685 | // Now it's sitting in the horizontal buffer ready to be distributed into the ring buffers. 1686 | } 1687 | 1688 | // Get the specified scan line from the ring buffer. 1689 | static float* stbir__get_ring_buffer_scanline(int get_scanline, float* ring_buffer, int begin_index, int first_scanline, int ring_buffer_num_entries, int ring_buffer_length) 1690 | { 1691 | int ring_buffer_index = (begin_index + (get_scanline - first_scanline)) % ring_buffer_num_entries; 1692 | return stbir__get_ring_buffer_entry(ring_buffer, ring_buffer_index, ring_buffer_length); 1693 | } 1694 | 1695 | 1696 | static void stbir__encode_scanline(stbir__info* stbir_info, int num_pixels, void *output_buffer, float *encode_buffer, int channels, int alpha_channel, int decode) 1697 | { 1698 | int x; 1699 | int n; 1700 | int num_nonalpha; 1701 | stbir_uint16 nonalpha[STBIR_MAX_CHANNELS]; 1702 | 1703 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_PREMULTIPLIED)) 1704 | { 1705 | for (x=0; x < num_pixels; ++x) 1706 | { 1707 | int pixel_index = x*channels; 1708 | 1709 | float alpha = encode_buffer[pixel_index + alpha_channel]; 1710 | float reciprocal_alpha = alpha ? 1.0f / alpha : 0; 1711 | 1712 | // unrolling this produced a 1% slowdown upscaling a large RGBA linear-space image on my machine - stb 1713 | for (n = 0; n < channels; n++) 1714 | if (n != alpha_channel) 1715 | encode_buffer[pixel_index + n] *= reciprocal_alpha; 1716 | 1717 | // We added in a small epsilon to prevent the color channel from being deleted with zero alpha. 1718 | // Because we only add it for integer types, it will automatically be discarded on integer 1719 | // conversion, so we don't need to subtract it back out (which would be problematic for 1720 | // numeric precision reasons). 1721 | } 1722 | } 1723 | 1724 | // build a table of all channels that need colorspace correction, so 1725 | // we don't perform colorspace correction on channels that don't need it. 1726 | for (x = 0, num_nonalpha = 0; x < channels; ++x) 1727 | { 1728 | if (x != alpha_channel || (stbir_info->flags & STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1729 | { 1730 | nonalpha[num_nonalpha++] = (stbir_uint16)x; 1731 | } 1732 | } 1733 | 1734 | #define STBIR__ROUND_INT(f) ((int) ((f)+0.5)) 1735 | #define STBIR__ROUND_UINT(f) ((stbir_uint32) ((f)+0.5)) 1736 | 1737 | #ifdef STBIR__SATURATE_INT 1738 | #define STBIR__ENCODE_LINEAR8(f) stbir__saturate8 (STBIR__ROUND_INT((f) * stbir__max_uint8_as_float )) 1739 | #define STBIR__ENCODE_LINEAR16(f) stbir__saturate16(STBIR__ROUND_INT((f) * stbir__max_uint16_as_float)) 1740 | #else 1741 | #define STBIR__ENCODE_LINEAR8(f) (unsigned char ) STBIR__ROUND_INT(stbir__saturate(f) * stbir__max_uint8_as_float ) 1742 | #define STBIR__ENCODE_LINEAR16(f) (unsigned short) STBIR__ROUND_INT(stbir__saturate(f) * stbir__max_uint16_as_float) 1743 | #endif 1744 | 1745 | switch (decode) 1746 | { 1747 | case STBIR__DECODE(STBIR_TYPE_UINT8, STBIR_COLORSPACE_LINEAR): 1748 | for (x=0; x < num_pixels; ++x) 1749 | { 1750 | int pixel_index = x*channels; 1751 | 1752 | for (n = 0; n < channels; n++) 1753 | { 1754 | int index = pixel_index + n; 1755 | ((unsigned char*)output_buffer)[index] = STBIR__ENCODE_LINEAR8(encode_buffer[index]); 1756 | } 1757 | } 1758 | break; 1759 | 1760 | case STBIR__DECODE(STBIR_TYPE_UINT8, STBIR_COLORSPACE_SRGB): 1761 | for (x=0; x < num_pixels; ++x) 1762 | { 1763 | int pixel_index = x*channels; 1764 | 1765 | for (n = 0; n < num_nonalpha; n++) 1766 | { 1767 | int index = pixel_index + nonalpha[n]; 1768 | ((unsigned char*)output_buffer)[index] = stbir__linear_to_srgb_uchar(encode_buffer[index]); 1769 | } 1770 | 1771 | if (!(stbir_info->flags & STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1772 | ((unsigned char *)output_buffer)[pixel_index + alpha_channel] = STBIR__ENCODE_LINEAR8(encode_buffer[pixel_index+alpha_channel]); 1773 | } 1774 | break; 1775 | 1776 | case STBIR__DECODE(STBIR_TYPE_UINT16, STBIR_COLORSPACE_LINEAR): 1777 | for (x=0; x < num_pixels; ++x) 1778 | { 1779 | int pixel_index = x*channels; 1780 | 1781 | for (n = 0; n < channels; n++) 1782 | { 1783 | int index = pixel_index + n; 1784 | ((unsigned short*)output_buffer)[index] = STBIR__ENCODE_LINEAR16(encode_buffer[index]); 1785 | } 1786 | } 1787 | break; 1788 | 1789 | case STBIR__DECODE(STBIR_TYPE_UINT16, STBIR_COLORSPACE_SRGB): 1790 | for (x=0; x < num_pixels; ++x) 1791 | { 1792 | int pixel_index = x*channels; 1793 | 1794 | for (n = 0; n < num_nonalpha; n++) 1795 | { 1796 | int index = pixel_index + nonalpha[n]; 1797 | ((unsigned short*)output_buffer)[index] = (unsigned short)STBIR__ROUND_INT(stbir__linear_to_srgb(stbir__saturate(encode_buffer[index])) * stbir__max_uint16_as_float); 1798 | } 1799 | 1800 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1801 | ((unsigned short*)output_buffer)[pixel_index + alpha_channel] = STBIR__ENCODE_LINEAR16(encode_buffer[pixel_index + alpha_channel]); 1802 | } 1803 | 1804 | break; 1805 | 1806 | case STBIR__DECODE(STBIR_TYPE_UINT32, STBIR_COLORSPACE_LINEAR): 1807 | for (x=0; x < num_pixels; ++x) 1808 | { 1809 | int pixel_index = x*channels; 1810 | 1811 | for (n = 0; n < channels; n++) 1812 | { 1813 | int index = pixel_index + n; 1814 | ((unsigned int*)output_buffer)[index] = (unsigned int)STBIR__ROUND_UINT(((double)stbir__saturate(encode_buffer[index])) * stbir__max_uint32_as_float); 1815 | } 1816 | } 1817 | break; 1818 | 1819 | case STBIR__DECODE(STBIR_TYPE_UINT32, STBIR_COLORSPACE_SRGB): 1820 | for (x=0; x < num_pixels; ++x) 1821 | { 1822 | int pixel_index = x*channels; 1823 | 1824 | for (n = 0; n < num_nonalpha; n++) 1825 | { 1826 | int index = pixel_index + nonalpha[n]; 1827 | ((unsigned int*)output_buffer)[index] = (unsigned int)STBIR__ROUND_UINT(((double)stbir__linear_to_srgb(stbir__saturate(encode_buffer[index]))) * stbir__max_uint32_as_float); 1828 | } 1829 | 1830 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1831 | ((unsigned int*)output_buffer)[pixel_index + alpha_channel] = (unsigned int)STBIR__ROUND_INT(((double)stbir__saturate(encode_buffer[pixel_index + alpha_channel])) * stbir__max_uint32_as_float); 1832 | } 1833 | break; 1834 | 1835 | case STBIR__DECODE(STBIR_TYPE_FLOAT, STBIR_COLORSPACE_LINEAR): 1836 | for (x=0; x < num_pixels; ++x) 1837 | { 1838 | int pixel_index = x*channels; 1839 | 1840 | for (n = 0; n < channels; n++) 1841 | { 1842 | int index = pixel_index + n; 1843 | ((float*)output_buffer)[index] = encode_buffer[index]; 1844 | } 1845 | } 1846 | break; 1847 | 1848 | case STBIR__DECODE(STBIR_TYPE_FLOAT, STBIR_COLORSPACE_SRGB): 1849 | for (x=0; x < num_pixels; ++x) 1850 | { 1851 | int pixel_index = x*channels; 1852 | 1853 | for (n = 0; n < num_nonalpha; n++) 1854 | { 1855 | int index = pixel_index + nonalpha[n]; 1856 | ((float*)output_buffer)[index] = stbir__linear_to_srgb(encode_buffer[index]); 1857 | } 1858 | 1859 | if (!(stbir_info->flags&STBIR_FLAG_ALPHA_USES_COLORSPACE)) 1860 | ((float*)output_buffer)[pixel_index + alpha_channel] = encode_buffer[pixel_index + alpha_channel]; 1861 | } 1862 | break; 1863 | 1864 | default: 1865 | STBIR_ASSERT(!"Unknown type/colorspace/channels combination."); 1866 | break; 1867 | } 1868 | } 1869 | 1870 | static void stbir__resample_vertical_upsample(stbir__info* stbir_info, int n) 1871 | { 1872 | int x, k; 1873 | int output_w = stbir_info->output_w; 1874 | stbir__contributors* vertical_contributors = stbir_info->vertical_contributors; 1875 | float* vertical_coefficients = stbir_info->vertical_coefficients; 1876 | int channels = stbir_info->channels; 1877 | int alpha_channel = stbir_info->alpha_channel; 1878 | int type = stbir_info->type; 1879 | int colorspace = stbir_info->colorspace; 1880 | int ring_buffer_entries = stbir_info->ring_buffer_num_entries; 1881 | void* output_data = stbir_info->output_data; 1882 | float* encode_buffer = stbir_info->encode_buffer; 1883 | int decode = STBIR__DECODE(type, colorspace); 1884 | int coefficient_width = stbir_info->vertical_coefficient_width; 1885 | int coefficient_counter; 1886 | int contributor = n; 1887 | 1888 | float* ring_buffer = stbir_info->ring_buffer; 1889 | int ring_buffer_begin_index = stbir_info->ring_buffer_begin_index; 1890 | int ring_buffer_first_scanline = stbir_info->ring_buffer_first_scanline; 1891 | int ring_buffer_length = stbir_info->ring_buffer_length_bytes/sizeof(float); 1892 | 1893 | int n0,n1, output_row_start; 1894 | int coefficient_group = coefficient_width * contributor; 1895 | 1896 | n0 = vertical_contributors[contributor].n0; 1897 | n1 = vertical_contributors[contributor].n1; 1898 | 1899 | output_row_start = n * stbir_info->output_stride_bytes; 1900 | 1901 | STBIR_ASSERT(stbir__use_height_upsampling(stbir_info)); 1902 | 1903 | memset(encode_buffer, 0, output_w * sizeof(float) * channels); 1904 | 1905 | // I tried reblocking this for better cache usage of encode_buffer 1906 | // (using x_outer, k, x_inner), but it lost speed. -- stb 1907 | 1908 | coefficient_counter = 0; 1909 | switch (channels) { 1910 | case 1: 1911 | for (k = n0; k <= n1; k++) 1912 | { 1913 | int coefficient_index = coefficient_counter++; 1914 | float* ring_buffer_entry = stbir__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, ring_buffer_entries, ring_buffer_length); 1915 | float coefficient = vertical_coefficients[coefficient_group + coefficient_index]; 1916 | for (x = 0; x < output_w; ++x) 1917 | { 1918 | int in_pixel_index = x * 1; 1919 | encode_buffer[in_pixel_index + 0] += ring_buffer_entry[in_pixel_index + 0] * coefficient; 1920 | } 1921 | } 1922 | break; 1923 | case 2: 1924 | for (k = n0; k <= n1; k++) 1925 | { 1926 | int coefficient_index = coefficient_counter++; 1927 | float* ring_buffer_entry = stbir__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, ring_buffer_entries, ring_buffer_length); 1928 | float coefficient = vertical_coefficients[coefficient_group + coefficient_index]; 1929 | for (x = 0; x < output_w; ++x) 1930 | { 1931 | int in_pixel_index = x * 2; 1932 | encode_buffer[in_pixel_index + 0] += ring_buffer_entry[in_pixel_index + 0] * coefficient; 1933 | encode_buffer[in_pixel_index + 1] += ring_buffer_entry[in_pixel_index + 1] * coefficient; 1934 | } 1935 | } 1936 | break; 1937 | case 3: 1938 | for (k = n0; k <= n1; k++) 1939 | { 1940 | int coefficient_index = coefficient_counter++; 1941 | float* ring_buffer_entry = stbir__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, ring_buffer_entries, ring_buffer_length); 1942 | float coefficient = vertical_coefficients[coefficient_group + coefficient_index]; 1943 | for (x = 0; x < output_w; ++x) 1944 | { 1945 | int in_pixel_index = x * 3; 1946 | encode_buffer[in_pixel_index + 0] += ring_buffer_entry[in_pixel_index + 0] * coefficient; 1947 | encode_buffer[in_pixel_index + 1] += ring_buffer_entry[in_pixel_index + 1] * coefficient; 1948 | encode_buffer[in_pixel_index + 2] += ring_buffer_entry[in_pixel_index + 2] * coefficient; 1949 | } 1950 | } 1951 | break; 1952 | case 4: 1953 | for (k = n0; k <= n1; k++) 1954 | { 1955 | int coefficient_index = coefficient_counter++; 1956 | float* ring_buffer_entry = stbir__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, ring_buffer_entries, ring_buffer_length); 1957 | float coefficient = vertical_coefficients[coefficient_group + coefficient_index]; 1958 | for (x = 0; x < output_w; ++x) 1959 | { 1960 | int in_pixel_index = x * 4; 1961 | encode_buffer[in_pixel_index + 0] += ring_buffer_entry[in_pixel_index + 0] * coefficient; 1962 | encode_buffer[in_pixel_index + 1] += ring_buffer_entry[in_pixel_index + 1] * coefficient; 1963 | encode_buffer[in_pixel_index + 2] += ring_buffer_entry[in_pixel_index + 2] * coefficient; 1964 | encode_buffer[in_pixel_index + 3] += ring_buffer_entry[in_pixel_index + 3] * coefficient; 1965 | } 1966 | } 1967 | break; 1968 | default: 1969 | for (k = n0; k <= n1; k++) 1970 | { 1971 | int coefficient_index = coefficient_counter++; 1972 | float* ring_buffer_entry = stbir__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, ring_buffer_entries, ring_buffer_length); 1973 | float coefficient = vertical_coefficients[coefficient_group + coefficient_index]; 1974 | for (x = 0; x < output_w; ++x) 1975 | { 1976 | int in_pixel_index = x * channels; 1977 | int c; 1978 | for (c = 0; c < channels; c++) 1979 | encode_buffer[in_pixel_index + c] += ring_buffer_entry[in_pixel_index + c] * coefficient; 1980 | } 1981 | } 1982 | break; 1983 | } 1984 | stbir__encode_scanline(stbir_info, output_w, (char *) output_data + output_row_start, encode_buffer, channels, alpha_channel, decode); 1985 | } 1986 | 1987 | static void stbir__resample_vertical_downsample(stbir__info* stbir_info, int n) 1988 | { 1989 | int x, k; 1990 | int output_w = stbir_info->output_w; 1991 | stbir__contributors* vertical_contributors = stbir_info->vertical_contributors; 1992 | float* vertical_coefficients = stbir_info->vertical_coefficients; 1993 | int channels = stbir_info->channels; 1994 | int ring_buffer_entries = stbir_info->ring_buffer_num_entries; 1995 | float* horizontal_buffer = stbir_info->horizontal_buffer; 1996 | int coefficient_width = stbir_info->vertical_coefficient_width; 1997 | int contributor = n + stbir_info->vertical_filter_pixel_margin; 1998 | 1999 | float* ring_buffer = stbir_info->ring_buffer; 2000 | int ring_buffer_begin_index = stbir_info->ring_buffer_begin_index; 2001 | int ring_buffer_first_scanline = stbir_info->ring_buffer_first_scanline; 2002 | int ring_buffer_length = stbir_info->ring_buffer_length_bytes/sizeof(float); 2003 | int n0,n1; 2004 | 2005 | n0 = vertical_contributors[contributor].n0; 2006 | n1 = vertical_contributors[contributor].n1; 2007 | 2008 | STBIR_ASSERT(!stbir__use_height_upsampling(stbir_info)); 2009 | 2010 | for (k = n0; k <= n1; k++) 2011 | { 2012 | int coefficient_index = k - n0; 2013 | int coefficient_group = coefficient_width * contributor; 2014 | float coefficient = vertical_coefficients[coefficient_group + coefficient_index]; 2015 | 2016 | float* ring_buffer_entry = stbir__get_ring_buffer_scanline(k, ring_buffer, ring_buffer_begin_index, ring_buffer_first_scanline, ring_buffer_entries, ring_buffer_length); 2017 | 2018 | switch (channels) { 2019 | case 1: 2020 | for (x = 0; x < output_w; x++) 2021 | { 2022 | int in_pixel_index = x * 1; 2023 | ring_buffer_entry[in_pixel_index + 0] += horizontal_buffer[in_pixel_index + 0] * coefficient; 2024 | } 2025 | break; 2026 | case 2: 2027 | for (x = 0; x < output_w; x++) 2028 | { 2029 | int in_pixel_index = x * 2; 2030 | ring_buffer_entry[in_pixel_index + 0] += horizontal_buffer[in_pixel_index + 0] * coefficient; 2031 | ring_buffer_entry[in_pixel_index + 1] += horizontal_buffer[in_pixel_index + 1] * coefficient; 2032 | } 2033 | break; 2034 | case 3: 2035 | for (x = 0; x < output_w; x++) 2036 | { 2037 | int in_pixel_index = x * 3; 2038 | ring_buffer_entry[in_pixel_index + 0] += horizontal_buffer[in_pixel_index + 0] * coefficient; 2039 | ring_buffer_entry[in_pixel_index + 1] += horizontal_buffer[in_pixel_index + 1] * coefficient; 2040 | ring_buffer_entry[in_pixel_index + 2] += horizontal_buffer[in_pixel_index + 2] * coefficient; 2041 | } 2042 | break; 2043 | case 4: 2044 | for (x = 0; x < output_w; x++) 2045 | { 2046 | int in_pixel_index = x * 4; 2047 | ring_buffer_entry[in_pixel_index + 0] += horizontal_buffer[in_pixel_index + 0] * coefficient; 2048 | ring_buffer_entry[in_pixel_index + 1] += horizontal_buffer[in_pixel_index + 1] * coefficient; 2049 | ring_buffer_entry[in_pixel_index + 2] += horizontal_buffer[in_pixel_index + 2] * coefficient; 2050 | ring_buffer_entry[in_pixel_index + 3] += horizontal_buffer[in_pixel_index + 3] * coefficient; 2051 | } 2052 | break; 2053 | default: 2054 | for (x = 0; x < output_w; x++) 2055 | { 2056 | int in_pixel_index = x * channels; 2057 | 2058 | int c; 2059 | for (c = 0; c < channels; c++) 2060 | ring_buffer_entry[in_pixel_index + c] += horizontal_buffer[in_pixel_index + c] * coefficient; 2061 | } 2062 | break; 2063 | } 2064 | } 2065 | } 2066 | 2067 | static void stbir__buffer_loop_upsample(stbir__info* stbir_info) 2068 | { 2069 | int y; 2070 | float scale_ratio = stbir_info->vertical_scale; 2071 | float out_scanlines_radius = stbir__filter_info_table[stbir_info->vertical_filter].support(1/scale_ratio) * scale_ratio; 2072 | 2073 | STBIR_ASSERT(stbir__use_height_upsampling(stbir_info)); 2074 | 2075 | for (y = 0; y < stbir_info->output_h; y++) 2076 | { 2077 | float in_center_of_out = 0; // Center of the current out scanline in the in scanline space 2078 | int in_first_scanline = 0, in_last_scanline = 0; 2079 | 2080 | stbir__calculate_sample_range_upsample(y, out_scanlines_radius, scale_ratio, stbir_info->vertical_shift, &in_first_scanline, &in_last_scanline, &in_center_of_out); 2081 | 2082 | STBIR_ASSERT(in_last_scanline - in_first_scanline + 1 <= stbir_info->ring_buffer_num_entries); 2083 | 2084 | if (stbir_info->ring_buffer_begin_index >= 0) 2085 | { 2086 | // Get rid of whatever we don't need anymore. 2087 | while (in_first_scanline > stbir_info->ring_buffer_first_scanline) 2088 | { 2089 | if (stbir_info->ring_buffer_first_scanline == stbir_info->ring_buffer_last_scanline) 2090 | { 2091 | // We just popped the last scanline off the ring buffer. 2092 | // Reset it to the empty state. 2093 | stbir_info->ring_buffer_begin_index = -1; 2094 | stbir_info->ring_buffer_first_scanline = 0; 2095 | stbir_info->ring_buffer_last_scanline = 0; 2096 | break; 2097 | } 2098 | else 2099 | { 2100 | stbir_info->ring_buffer_first_scanline++; 2101 | stbir_info->ring_buffer_begin_index = (stbir_info->ring_buffer_begin_index + 1) % stbir_info->ring_buffer_num_entries; 2102 | } 2103 | } 2104 | } 2105 | 2106 | // Load in new ones. 2107 | if (stbir_info->ring_buffer_begin_index < 0) 2108 | stbir__decode_and_resample_upsample(stbir_info, in_first_scanline); 2109 | 2110 | while (in_last_scanline > stbir_info->ring_buffer_last_scanline) 2111 | stbir__decode_and_resample_upsample(stbir_info, stbir_info->ring_buffer_last_scanline + 1); 2112 | 2113 | // Now all buffers should be ready to write a row of vertical sampling. 2114 | stbir__resample_vertical_upsample(stbir_info, y); 2115 | 2116 | STBIR_PROGRESS_REPORT((float)y / stbir_info->output_h); 2117 | } 2118 | } 2119 | 2120 | static void stbir__empty_ring_buffer(stbir__info* stbir_info, int first_necessary_scanline) 2121 | { 2122 | int output_stride_bytes = stbir_info->output_stride_bytes; 2123 | int channels = stbir_info->channels; 2124 | int alpha_channel = stbir_info->alpha_channel; 2125 | int type = stbir_info->type; 2126 | int colorspace = stbir_info->colorspace; 2127 | int output_w = stbir_info->output_w; 2128 | void* output_data = stbir_info->output_data; 2129 | int decode = STBIR__DECODE(type, colorspace); 2130 | 2131 | float* ring_buffer = stbir_info->ring_buffer; 2132 | int ring_buffer_length = stbir_info->ring_buffer_length_bytes/sizeof(float); 2133 | 2134 | if (stbir_info->ring_buffer_begin_index >= 0) 2135 | { 2136 | // Get rid of whatever we don't need anymore. 2137 | while (first_necessary_scanline > stbir_info->ring_buffer_first_scanline) 2138 | { 2139 | if (stbir_info->ring_buffer_first_scanline >= 0 && stbir_info->ring_buffer_first_scanline < stbir_info->output_h) 2140 | { 2141 | int output_row_start = stbir_info->ring_buffer_first_scanline * output_stride_bytes; 2142 | float* ring_buffer_entry = stbir__get_ring_buffer_entry(ring_buffer, stbir_info->ring_buffer_begin_index, ring_buffer_length); 2143 | stbir__encode_scanline(stbir_info, output_w, (char *) output_data + output_row_start, ring_buffer_entry, channels, alpha_channel, decode); 2144 | STBIR_PROGRESS_REPORT((float)stbir_info->ring_buffer_first_scanline / stbir_info->output_h); 2145 | } 2146 | 2147 | if (stbir_info->ring_buffer_first_scanline == stbir_info->ring_buffer_last_scanline) 2148 | { 2149 | // We just popped the last scanline off the ring buffer. 2150 | // Reset it to the empty state. 2151 | stbir_info->ring_buffer_begin_index = -1; 2152 | stbir_info->ring_buffer_first_scanline = 0; 2153 | stbir_info->ring_buffer_last_scanline = 0; 2154 | break; 2155 | } 2156 | else 2157 | { 2158 | stbir_info->ring_buffer_first_scanline++; 2159 | stbir_info->ring_buffer_begin_index = (stbir_info->ring_buffer_begin_index + 1) % stbir_info->ring_buffer_num_entries; 2160 | } 2161 | } 2162 | } 2163 | } 2164 | 2165 | static void stbir__buffer_loop_downsample(stbir__info* stbir_info) 2166 | { 2167 | int y; 2168 | float scale_ratio = stbir_info->vertical_scale; 2169 | int output_h = stbir_info->output_h; 2170 | float in_pixels_radius = stbir__filter_info_table[stbir_info->vertical_filter].support(scale_ratio) / scale_ratio; 2171 | int pixel_margin = stbir_info->vertical_filter_pixel_margin; 2172 | int max_y = stbir_info->input_h + pixel_margin; 2173 | 2174 | STBIR_ASSERT(!stbir__use_height_upsampling(stbir_info)); 2175 | 2176 | for (y = -pixel_margin; y < max_y; y++) 2177 | { 2178 | float out_center_of_in; // Center of the current out scanline in the in scanline space 2179 | int out_first_scanline, out_last_scanline; 2180 | 2181 | stbir__calculate_sample_range_downsample(y, in_pixels_radius, scale_ratio, stbir_info->vertical_shift, &out_first_scanline, &out_last_scanline, &out_center_of_in); 2182 | 2183 | STBIR_ASSERT(out_last_scanline - out_first_scanline + 1 <= stbir_info->ring_buffer_num_entries); 2184 | 2185 | if (out_last_scanline < 0 || out_first_scanline >= output_h) 2186 | continue; 2187 | 2188 | stbir__empty_ring_buffer(stbir_info, out_first_scanline); 2189 | 2190 | stbir__decode_and_resample_downsample(stbir_info, y); 2191 | 2192 | // Load in new ones. 2193 | if (stbir_info->ring_buffer_begin_index < 0) 2194 | stbir__add_empty_ring_buffer_entry(stbir_info, out_first_scanline); 2195 | 2196 | while (out_last_scanline > stbir_info->ring_buffer_last_scanline) 2197 | stbir__add_empty_ring_buffer_entry(stbir_info, stbir_info->ring_buffer_last_scanline + 1); 2198 | 2199 | // Now the horizontal buffer is ready to write to all ring buffer rows. 2200 | stbir__resample_vertical_downsample(stbir_info, y); 2201 | } 2202 | 2203 | stbir__empty_ring_buffer(stbir_info, stbir_info->output_h); 2204 | } 2205 | 2206 | static void stbir__setup(stbir__info *info, int input_w, int input_h, int output_w, int output_h, int channels) 2207 | { 2208 | info->input_w = input_w; 2209 | info->input_h = input_h; 2210 | info->output_w = output_w; 2211 | info->output_h = output_h; 2212 | info->channels = channels; 2213 | } 2214 | 2215 | static void stbir__calculate_transform(stbir__info *info, float s0, float t0, float s1, float t1, float *transform) 2216 | { 2217 | info->s0 = s0; 2218 | info->t0 = t0; 2219 | info->s1 = s1; 2220 | info->t1 = t1; 2221 | 2222 | if (transform) 2223 | { 2224 | info->horizontal_scale = transform[0]; 2225 | info->vertical_scale = transform[1]; 2226 | info->horizontal_shift = transform[2]; 2227 | info->vertical_shift = transform[3]; 2228 | } 2229 | else 2230 | { 2231 | info->horizontal_scale = ((float)info->output_w / info->input_w) / (s1 - s0); 2232 | info->vertical_scale = ((float)info->output_h / info->input_h) / (t1 - t0); 2233 | 2234 | info->horizontal_shift = s0 * info->output_w / (s1 - s0); 2235 | info->vertical_shift = t0 * info->output_h / (t1 - t0); 2236 | } 2237 | } 2238 | 2239 | static void stbir__choose_filter(stbir__info *info, stbir_filter h_filter, stbir_filter v_filter) 2240 | { 2241 | if (h_filter == 0) 2242 | h_filter = stbir__use_upsampling(info->horizontal_scale) ? STBIR_DEFAULT_FILTER_UPSAMPLE : STBIR_DEFAULT_FILTER_DOWNSAMPLE; 2243 | if (v_filter == 0) 2244 | v_filter = stbir__use_upsampling(info->vertical_scale) ? STBIR_DEFAULT_FILTER_UPSAMPLE : STBIR_DEFAULT_FILTER_DOWNSAMPLE; 2245 | info->horizontal_filter = h_filter; 2246 | info->vertical_filter = v_filter; 2247 | } 2248 | 2249 | static stbir_uint32 stbir__calculate_memory(stbir__info *info) 2250 | { 2251 | int pixel_margin = stbir__get_filter_pixel_margin(info->horizontal_filter, info->horizontal_scale); 2252 | int filter_height = stbir__get_filter_pixel_width(info->vertical_filter, info->vertical_scale); 2253 | 2254 | info->horizontal_num_contributors = stbir__get_contributors(info->horizontal_scale, info->horizontal_filter, info->input_w, info->output_w); 2255 | info->vertical_num_contributors = stbir__get_contributors(info->vertical_scale , info->vertical_filter , info->input_h, info->output_h); 2256 | 2257 | // One extra entry because floating point precision problems sometimes cause an extra to be necessary. 2258 | info->ring_buffer_num_entries = filter_height + 1; 2259 | 2260 | info->horizontal_contributors_size = info->horizontal_num_contributors * sizeof(stbir__contributors); 2261 | info->horizontal_coefficients_size = stbir__get_total_horizontal_coefficients(info) * sizeof(float); 2262 | info->vertical_contributors_size = info->vertical_num_contributors * sizeof(stbir__contributors); 2263 | info->vertical_coefficients_size = stbir__get_total_vertical_coefficients(info) * sizeof(float); 2264 | info->decode_buffer_size = (info->input_w + pixel_margin * 2) * info->channels * sizeof(float); 2265 | info->horizontal_buffer_size = info->output_w * info->channels * sizeof(float); 2266 | info->ring_buffer_size = info->output_w * info->channels * info->ring_buffer_num_entries * sizeof(float); 2267 | info->encode_buffer_size = info->output_w * info->channels * sizeof(float); 2268 | 2269 | STBIR_ASSERT(info->horizontal_filter != 0); 2270 | STBIR_ASSERT(info->horizontal_filter < STBIR__ARRAY_SIZE(stbir__filter_info_table)); // this now happens too late 2271 | STBIR_ASSERT(info->vertical_filter != 0); 2272 | STBIR_ASSERT(info->vertical_filter < STBIR__ARRAY_SIZE(stbir__filter_info_table)); // this now happens too late 2273 | 2274 | if (stbir__use_height_upsampling(info)) 2275 | // The horizontal buffer is for when we're downsampling the height and we 2276 | // can't output the result of sampling the decode buffer directly into the 2277 | // ring buffers. 2278 | info->horizontal_buffer_size = 0; 2279 | else 2280 | // The encode buffer is to retain precision in the height upsampling method 2281 | // and isn't used when height downsampling. 2282 | info->encode_buffer_size = 0; 2283 | 2284 | return info->horizontal_contributors_size + info->horizontal_coefficients_size 2285 | + info->vertical_contributors_size + info->vertical_coefficients_size 2286 | + info->decode_buffer_size + info->horizontal_buffer_size 2287 | + info->ring_buffer_size + info->encode_buffer_size; 2288 | } 2289 | 2290 | static int stbir__resize_allocated(stbir__info *info, 2291 | const void* input_data, int input_stride_in_bytes, 2292 | void* output_data, int output_stride_in_bytes, 2293 | int alpha_channel, stbir_uint32 flags, stbir_datatype type, 2294 | stbir_edge edge_horizontal, stbir_edge edge_vertical, stbir_colorspace colorspace, 2295 | void* tempmem, size_t tempmem_size_in_bytes) 2296 | { 2297 | size_t memory_required = stbir__calculate_memory(info); 2298 | 2299 | int width_stride_input = input_stride_in_bytes ? input_stride_in_bytes : info->channels * info->input_w * stbir__type_size[type]; 2300 | int width_stride_output = output_stride_in_bytes ? output_stride_in_bytes : info->channels * info->output_w * stbir__type_size[type]; 2301 | 2302 | #ifdef STBIR_DEBUG_OVERWRITE_TEST 2303 | #define OVERWRITE_ARRAY_SIZE 8 2304 | unsigned char overwrite_output_before_pre[OVERWRITE_ARRAY_SIZE]; 2305 | unsigned char overwrite_tempmem_before_pre[OVERWRITE_ARRAY_SIZE]; 2306 | unsigned char overwrite_output_after_pre[OVERWRITE_ARRAY_SIZE]; 2307 | unsigned char overwrite_tempmem_after_pre[OVERWRITE_ARRAY_SIZE]; 2308 | 2309 | size_t begin_forbidden = width_stride_output * (info->output_h - 1) + info->output_w * info->channels * stbir__type_size[type]; 2310 | memcpy(overwrite_output_before_pre, &((unsigned char*)output_data)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE); 2311 | memcpy(overwrite_output_after_pre, &((unsigned char*)output_data)[begin_forbidden], OVERWRITE_ARRAY_SIZE); 2312 | memcpy(overwrite_tempmem_before_pre, &((unsigned char*)tempmem)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE); 2313 | memcpy(overwrite_tempmem_after_pre, &((unsigned char*)tempmem)[tempmem_size_in_bytes], OVERWRITE_ARRAY_SIZE); 2314 | #endif 2315 | 2316 | STBIR_ASSERT(info->channels >= 0); 2317 | STBIR_ASSERT(info->channels <= STBIR_MAX_CHANNELS); 2318 | 2319 | if (info->channels < 0 || info->channels > STBIR_MAX_CHANNELS) 2320 | return 0; 2321 | 2322 | STBIR_ASSERT(info->horizontal_filter < STBIR__ARRAY_SIZE(stbir__filter_info_table)); 2323 | STBIR_ASSERT(info->vertical_filter < STBIR__ARRAY_SIZE(stbir__filter_info_table)); 2324 | 2325 | if (info->horizontal_filter >= STBIR__ARRAY_SIZE(stbir__filter_info_table)) 2326 | return 0; 2327 | if (info->vertical_filter >= STBIR__ARRAY_SIZE(stbir__filter_info_table)) 2328 | return 0; 2329 | 2330 | if (alpha_channel < 0) 2331 | flags |= STBIR_FLAG_ALPHA_USES_COLORSPACE | STBIR_FLAG_ALPHA_PREMULTIPLIED; 2332 | 2333 | if (!(flags&STBIR_FLAG_ALPHA_USES_COLORSPACE) || !(flags&STBIR_FLAG_ALPHA_PREMULTIPLIED)) { 2334 | STBIR_ASSERT(alpha_channel >= 0 && alpha_channel < info->channels); 2335 | } 2336 | 2337 | if (alpha_channel >= info->channels) 2338 | return 0; 2339 | 2340 | STBIR_ASSERT(tempmem); 2341 | 2342 | if (!tempmem) 2343 | return 0; 2344 | 2345 | STBIR_ASSERT(tempmem_size_in_bytes >= memory_required); 2346 | 2347 | if (tempmem_size_in_bytes < memory_required) 2348 | return 0; 2349 | 2350 | memset(tempmem, 0, tempmem_size_in_bytes); 2351 | 2352 | info->input_data = input_data; 2353 | info->input_stride_bytes = width_stride_input; 2354 | 2355 | info->output_data = output_data; 2356 | info->output_stride_bytes = width_stride_output; 2357 | 2358 | info->alpha_channel = alpha_channel; 2359 | info->flags = flags; 2360 | info->type = type; 2361 | info->edge_horizontal = edge_horizontal; 2362 | info->edge_vertical = edge_vertical; 2363 | info->colorspace = colorspace; 2364 | 2365 | info->horizontal_coefficient_width = stbir__get_coefficient_width (info->horizontal_filter, info->horizontal_scale); 2366 | info->vertical_coefficient_width = stbir__get_coefficient_width (info->vertical_filter , info->vertical_scale ); 2367 | info->horizontal_filter_pixel_width = stbir__get_filter_pixel_width (info->horizontal_filter, info->horizontal_scale); 2368 | info->vertical_filter_pixel_width = stbir__get_filter_pixel_width (info->vertical_filter , info->vertical_scale ); 2369 | info->horizontal_filter_pixel_margin = stbir__get_filter_pixel_margin(info->horizontal_filter, info->horizontal_scale); 2370 | info->vertical_filter_pixel_margin = stbir__get_filter_pixel_margin(info->vertical_filter , info->vertical_scale ); 2371 | 2372 | info->ring_buffer_length_bytes = info->output_w * info->channels * sizeof(float); 2373 | info->decode_buffer_pixels = info->input_w + info->horizontal_filter_pixel_margin * 2; 2374 | 2375 | #define STBIR__NEXT_MEMPTR(current, newtype) (newtype*)(((unsigned char*)current) + current##_size) 2376 | 2377 | info->horizontal_contributors = (stbir__contributors *) tempmem; 2378 | info->horizontal_coefficients = STBIR__NEXT_MEMPTR(info->horizontal_contributors, float); 2379 | info->vertical_contributors = STBIR__NEXT_MEMPTR(info->horizontal_coefficients, stbir__contributors); 2380 | info->vertical_coefficients = STBIR__NEXT_MEMPTR(info->vertical_contributors, float); 2381 | info->decode_buffer = STBIR__NEXT_MEMPTR(info->vertical_coefficients, float); 2382 | 2383 | if (stbir__use_height_upsampling(info)) 2384 | { 2385 | info->horizontal_buffer = NULL; 2386 | info->ring_buffer = STBIR__NEXT_MEMPTR(info->decode_buffer, float); 2387 | info->encode_buffer = STBIR__NEXT_MEMPTR(info->ring_buffer, float); 2388 | 2389 | STBIR_ASSERT((size_t)STBIR__NEXT_MEMPTR(info->encode_buffer, unsigned char) == (size_t)tempmem + tempmem_size_in_bytes); 2390 | } 2391 | else 2392 | { 2393 | info->horizontal_buffer = STBIR__NEXT_MEMPTR(info->decode_buffer, float); 2394 | info->ring_buffer = STBIR__NEXT_MEMPTR(info->horizontal_buffer, float); 2395 | info->encode_buffer = NULL; 2396 | 2397 | STBIR_ASSERT((size_t)STBIR__NEXT_MEMPTR(info->ring_buffer, unsigned char) == (size_t)tempmem + tempmem_size_in_bytes); 2398 | } 2399 | 2400 | #undef STBIR__NEXT_MEMPTR 2401 | 2402 | // This signals that the ring buffer is empty 2403 | info->ring_buffer_begin_index = -1; 2404 | 2405 | stbir__calculate_filters(info->horizontal_contributors, info->horizontal_coefficients, info->horizontal_filter, info->horizontal_scale, info->horizontal_shift, info->input_w, info->output_w); 2406 | stbir__calculate_filters(info->vertical_contributors, info->vertical_coefficients, info->vertical_filter, info->vertical_scale, info->vertical_shift, info->input_h, info->output_h); 2407 | 2408 | STBIR_PROGRESS_REPORT(0); 2409 | 2410 | if (stbir__use_height_upsampling(info)) 2411 | stbir__buffer_loop_upsample(info); 2412 | else 2413 | stbir__buffer_loop_downsample(info); 2414 | 2415 | STBIR_PROGRESS_REPORT(1); 2416 | 2417 | #ifdef STBIR_DEBUG_OVERWRITE_TEST 2418 | STBIR_ASSERT(memcmp(overwrite_output_before_pre, &((unsigned char*)output_data)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE) == 0); 2419 | STBIR_ASSERT(memcmp(overwrite_output_after_pre, &((unsigned char*)output_data)[begin_forbidden], OVERWRITE_ARRAY_SIZE) == 0); 2420 | STBIR_ASSERT(memcmp(overwrite_tempmem_before_pre, &((unsigned char*)tempmem)[-OVERWRITE_ARRAY_SIZE], OVERWRITE_ARRAY_SIZE) == 0); 2421 | STBIR_ASSERT(memcmp(overwrite_tempmem_after_pre, &((unsigned char*)tempmem)[tempmem_size_in_bytes], OVERWRITE_ARRAY_SIZE) == 0); 2422 | #endif 2423 | 2424 | return 1; 2425 | } 2426 | 2427 | 2428 | static int stbir__resize_arbitrary( 2429 | void *alloc_context, 2430 | const void* input_data, int input_w, int input_h, int input_stride_in_bytes, 2431 | void* output_data, int output_w, int output_h, int output_stride_in_bytes, 2432 | float s0, float t0, float s1, float t1, float *transform, 2433 | int channels, int alpha_channel, stbir_uint32 flags, stbir_datatype type, 2434 | stbir_filter h_filter, stbir_filter v_filter, 2435 | stbir_edge edge_horizontal, stbir_edge edge_vertical, stbir_colorspace colorspace) 2436 | { 2437 | stbir__info info; 2438 | int result; 2439 | size_t memory_required; 2440 | void* extra_memory; 2441 | 2442 | stbir__setup(&info, input_w, input_h, output_w, output_h, channels); 2443 | stbir__calculate_transform(&info, s0,t0,s1,t1,transform); 2444 | stbir__choose_filter(&info, h_filter, v_filter); 2445 | memory_required = stbir__calculate_memory(&info); 2446 | extra_memory = STBIR_MALLOC(memory_required, alloc_context); 2447 | 2448 | if (!extra_memory) 2449 | return 0; 2450 | 2451 | result = stbir__resize_allocated(&info, input_data, input_stride_in_bytes, 2452 | output_data, output_stride_in_bytes, 2453 | alpha_channel, flags, type, 2454 | edge_horizontal, edge_vertical, 2455 | colorspace, extra_memory, memory_required); 2456 | 2457 | STBIR_FREE(extra_memory, alloc_context); 2458 | 2459 | return result; 2460 | } 2461 | 2462 | STBIRDEF int stbir_resize_uint8( const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2463 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2464 | int num_channels) 2465 | { 2466 | return stbir__resize_arbitrary(NULL, input_pixels, input_w, input_h, input_stride_in_bytes, 2467 | output_pixels, output_w, output_h, output_stride_in_bytes, 2468 | 0,0,1,1,NULL,num_channels,-1,0, STBIR_TYPE_UINT8, STBIR_FILTER_DEFAULT, STBIR_FILTER_DEFAULT, 2469 | STBIR_EDGE_CLAMP, STBIR_EDGE_CLAMP, STBIR_COLORSPACE_LINEAR); 2470 | } 2471 | 2472 | STBIRDEF int stbir_resize_float( const float *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2473 | float *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2474 | int num_channels) 2475 | { 2476 | return stbir__resize_arbitrary(NULL, input_pixels, input_w, input_h, input_stride_in_bytes, 2477 | output_pixels, output_w, output_h, output_stride_in_bytes, 2478 | 0,0,1,1,NULL,num_channels,-1,0, STBIR_TYPE_FLOAT, STBIR_FILTER_DEFAULT, STBIR_FILTER_DEFAULT, 2479 | STBIR_EDGE_CLAMP, STBIR_EDGE_CLAMP, STBIR_COLORSPACE_LINEAR); 2480 | } 2481 | 2482 | STBIRDEF int stbir_resize_uint8_srgb(const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2483 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2484 | int num_channels, int alpha_channel, int flags) 2485 | { 2486 | return stbir__resize_arbitrary(NULL, input_pixels, input_w, input_h, input_stride_in_bytes, 2487 | output_pixels, output_w, output_h, output_stride_in_bytes, 2488 | 0,0,1,1,NULL,num_channels,alpha_channel,flags, STBIR_TYPE_UINT8, STBIR_FILTER_DEFAULT, STBIR_FILTER_DEFAULT, 2489 | STBIR_EDGE_CLAMP, STBIR_EDGE_CLAMP, STBIR_COLORSPACE_SRGB); 2490 | } 2491 | 2492 | STBIRDEF int stbir_resize_uint8_srgb_edgemode(const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2493 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2494 | int num_channels, int alpha_channel, int flags, 2495 | stbir_edge edge_wrap_mode) 2496 | { 2497 | return stbir__resize_arbitrary(NULL, input_pixels, input_w, input_h, input_stride_in_bytes, 2498 | output_pixels, output_w, output_h, output_stride_in_bytes, 2499 | 0,0,1,1,NULL,num_channels,alpha_channel,flags, STBIR_TYPE_UINT8, STBIR_FILTER_DEFAULT, STBIR_FILTER_DEFAULT, 2500 | edge_wrap_mode, edge_wrap_mode, STBIR_COLORSPACE_SRGB); 2501 | } 2502 | 2503 | STBIRDEF int stbir_resize_uint8_generic( const unsigned char *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2504 | unsigned char *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2505 | int num_channels, int alpha_channel, int flags, 2506 | stbir_edge edge_wrap_mode, stbir_filter filter, stbir_colorspace space, 2507 | void *alloc_context) 2508 | { 2509 | return stbir__resize_arbitrary(alloc_context, input_pixels, input_w, input_h, input_stride_in_bytes, 2510 | output_pixels, output_w, output_h, output_stride_in_bytes, 2511 | 0,0,1,1,NULL,num_channels,alpha_channel,flags, STBIR_TYPE_UINT8, filter, filter, 2512 | edge_wrap_mode, edge_wrap_mode, space); 2513 | } 2514 | 2515 | STBIRDEF int stbir_resize_uint16_generic(const stbir_uint16 *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2516 | stbir_uint16 *output_pixels , int output_w, int output_h, int output_stride_in_bytes, 2517 | int num_channels, int alpha_channel, int flags, 2518 | stbir_edge edge_wrap_mode, stbir_filter filter, stbir_colorspace space, 2519 | void *alloc_context) 2520 | { 2521 | return stbir__resize_arbitrary(alloc_context, input_pixels, input_w, input_h, input_stride_in_bytes, 2522 | output_pixels, output_w, output_h, output_stride_in_bytes, 2523 | 0,0,1,1,NULL,num_channels,alpha_channel,flags, STBIR_TYPE_UINT16, filter, filter, 2524 | edge_wrap_mode, edge_wrap_mode, space); 2525 | } 2526 | 2527 | 2528 | STBIRDEF int stbir_resize_float_generic( const float *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2529 | float *output_pixels , int output_w, int output_h, int output_stride_in_bytes, 2530 | int num_channels, int alpha_channel, int flags, 2531 | stbir_edge edge_wrap_mode, stbir_filter filter, stbir_colorspace space, 2532 | void *alloc_context) 2533 | { 2534 | return stbir__resize_arbitrary(alloc_context, input_pixels, input_w, input_h, input_stride_in_bytes, 2535 | output_pixels, output_w, output_h, output_stride_in_bytes, 2536 | 0,0,1,1,NULL,num_channels,alpha_channel,flags, STBIR_TYPE_FLOAT, filter, filter, 2537 | edge_wrap_mode, edge_wrap_mode, space); 2538 | } 2539 | 2540 | 2541 | STBIRDEF int stbir_resize( const void *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2542 | void *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2543 | stbir_datatype datatype, 2544 | int num_channels, int alpha_channel, int flags, 2545 | stbir_edge edge_mode_horizontal, stbir_edge edge_mode_vertical, 2546 | stbir_filter filter_horizontal, stbir_filter filter_vertical, 2547 | stbir_colorspace space, void *alloc_context) 2548 | { 2549 | return stbir__resize_arbitrary(alloc_context, input_pixels, input_w, input_h, input_stride_in_bytes, 2550 | output_pixels, output_w, output_h, output_stride_in_bytes, 2551 | 0,0,1,1,NULL,num_channels,alpha_channel,flags, datatype, filter_horizontal, filter_vertical, 2552 | edge_mode_horizontal, edge_mode_vertical, space); 2553 | } 2554 | 2555 | 2556 | STBIRDEF int stbir_resize_subpixel(const void *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2557 | void *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2558 | stbir_datatype datatype, 2559 | int num_channels, int alpha_channel, int flags, 2560 | stbir_edge edge_mode_horizontal, stbir_edge edge_mode_vertical, 2561 | stbir_filter filter_horizontal, stbir_filter filter_vertical, 2562 | stbir_colorspace space, void *alloc_context, 2563 | float x_scale, float y_scale, 2564 | float x_offset, float y_offset) 2565 | { 2566 | float transform[4]; 2567 | transform[0] = x_scale; 2568 | transform[1] = y_scale; 2569 | transform[2] = x_offset; 2570 | transform[3] = y_offset; 2571 | return stbir__resize_arbitrary(alloc_context, input_pixels, input_w, input_h, input_stride_in_bytes, 2572 | output_pixels, output_w, output_h, output_stride_in_bytes, 2573 | 0,0,1,1,transform,num_channels,alpha_channel,flags, datatype, filter_horizontal, filter_vertical, 2574 | edge_mode_horizontal, edge_mode_vertical, space); 2575 | } 2576 | 2577 | STBIRDEF int stbir_resize_region( const void *input_pixels , int input_w , int input_h , int input_stride_in_bytes, 2578 | void *output_pixels, int output_w, int output_h, int output_stride_in_bytes, 2579 | stbir_datatype datatype, 2580 | int num_channels, int alpha_channel, int flags, 2581 | stbir_edge edge_mode_horizontal, stbir_edge edge_mode_vertical, 2582 | stbir_filter filter_horizontal, stbir_filter filter_vertical, 2583 | stbir_colorspace space, void *alloc_context, 2584 | float s0, float t0, float s1, float t1) 2585 | { 2586 | return stbir__resize_arbitrary(alloc_context, input_pixels, input_w, input_h, input_stride_in_bytes, 2587 | output_pixels, output_w, output_h, output_stride_in_bytes, 2588 | s0,t0,s1,t1,NULL,num_channels,alpha_channel,flags, datatype, filter_horizontal, filter_vertical, 2589 | edge_mode_horizontal, edge_mode_vertical, space); 2590 | } 2591 | 2592 | #endif // STB_IMAGE_RESIZE_IMPLEMENTATION 2593 | 2594 | /* 2595 | ------------------------------------------------------------------------------ 2596 | This software is available under 2 licenses -- choose whichever you prefer. 2597 | ------------------------------------------------------------------------------ 2598 | ALTERNATIVE A - MIT License 2599 | Copyright (c) 2017 Sean Barrett 2600 | Permission is hereby granted, free of charge, to any person obtaining a copy of 2601 | this software and associated documentation files (the "Software"), to deal in 2602 | the Software without restriction, including without limitation the rights to 2603 | use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 2604 | of the Software, and to permit persons to whom the Software is furnished to do 2605 | so, subject to the following conditions: 2606 | The above copyright notice and this permission notice shall be included in all 2607 | copies or substantial portions of the Software. 2608 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 2609 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 2610 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 2611 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 2612 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 2613 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 2614 | SOFTWARE. 2615 | ------------------------------------------------------------------------------ 2616 | ALTERNATIVE B - Public Domain (www.unlicense.org) 2617 | This is free and unencumbered software released into the public domain. 2618 | Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 2619 | software, either in source code form or as a compiled binary, for any purpose, 2620 | commercial or non-commercial, and by any means. 2621 | In jurisdictions that recognize copyright laws, the author or authors of this 2622 | software dedicate any and all copyright interest in the software to the public 2623 | domain. We make this dedication for the benefit of the public at large and to 2624 | the detriment of our heirs and successors. We intend this dedication to be an 2625 | overt act of relinquishment in perpetuity of all present and future rights to 2626 | this software under copyright law. 2627 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 2628 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 2629 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 2630 | AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 2631 | ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 2632 | WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 2633 | ------------------------------------------------------------------------------ 2634 | */ 2635 | --------------------------------------------------------------------------------