1 // Copyright 2011 Google Inc. All Rights Reserved. 2 // 3 // This code is licensed under the same terms as WebM: 4 // Software License Agreement: http://www.webmproject.org/license/software/ 5 // Additional IP Rights Grant: http://www.webmproject.org/license/additional/ 6 // ----------------------------------------------------------------------------- 7 // 8 // WebPPicture utils: colorspace conversion, crop, ... 9 // 10 // Author: Skal (pascal.massimino (at) gmail.com) 11 12 #include <assert.h> 13 #include <stdlib.h> 14 #include <math.h> 15 16 #include "./vp8enci.h" 17 #include "../utils/rescaler.h" 18 #include "../utils/utils.h" 19 #include "../dsp/dsp.h" 20 #include "../dsp/yuv.h" 21 22 #if defined(__cplusplus) || defined(c_plusplus) 23 extern "C" { 24 #endif 25 26 #define HALVE(x) (((x) + 1) >> 1) 27 #define IS_YUV_CSP(csp, YUV_CSP) (((csp) & WEBP_CSP_UV_MASK) == (YUV_CSP)) 28 29 static const union { 30 uint32_t argb; 31 uint8_t bytes[4]; 32 } test_endian = { 0xff000000u }; 33 #define ALPHA_IS_LAST (test_endian.bytes[3] == 0xff) 34 35 //------------------------------------------------------------------------------ 36 // WebPPicture 37 //------------------------------------------------------------------------------ 38 39 int WebPPictureAlloc(WebPPicture* picture) { 40 if (picture != NULL) { 41 const WebPEncCSP uv_csp = picture->colorspace & WEBP_CSP_UV_MASK; 42 const int has_alpha = picture->colorspace & WEBP_CSP_ALPHA_BIT; 43 const int width = picture->width; 44 const int height = picture->height; 45 46 if (!picture->use_argb) { 47 const int y_stride = width; 48 const int uv_width = HALVE(width); 49 const int uv_height = HALVE(height); 50 const int uv_stride = uv_width; 51 int uv0_stride = 0; 52 int a_width, a_stride; 53 uint64_t y_size, uv_size, uv0_size, a_size, total_size; 54 uint8_t* mem; 55 56 // U/V 57 switch (uv_csp) { 58 case WEBP_YUV420: 59 break; 60 #ifdef WEBP_EXPERIMENTAL_FEATURES 61 case WEBP_YUV400: // for now, we'll just reset the U/V samples 62 break; 63 case WEBP_YUV422: 64 uv0_stride = uv_width; 65 break; 66 case WEBP_YUV444: 67 uv0_stride = width; 68 break; 69 #endif 70 default: 71 return 0; 72 } 73 uv0_size = height * uv0_stride; 74 75 // alpha 76 a_width = has_alpha ? width : 0; 77 a_stride = a_width; 78 y_size = (uint64_t)y_stride * height; 79 uv_size = (uint64_t)uv_stride * uv_height; 80 a_size = (uint64_t)a_stride * height; 81 82 total_size = y_size + a_size + 2 * uv_size + 2 * uv0_size; 83 84 // Security and validation checks 85 if (width <= 0 || height <= 0 || // luma/alpha param error 86 uv_width < 0 || uv_height < 0) { // u/v param error 87 return 0; 88 } 89 // Clear previous buffer and allocate a new one. 90 WebPPictureFree(picture); // erase previous buffer 91 mem = (uint8_t*)WebPSafeMalloc(total_size, sizeof(*mem)); 92 if (mem == NULL) return 0; 93 94 // From now on, we're in the clear, we can no longer fail... 95 picture->memory_ = (void*)mem; 96 picture->y_stride = y_stride; 97 picture->uv_stride = uv_stride; 98 picture->a_stride = a_stride; 99 picture->uv0_stride = uv0_stride; 100 // TODO(skal): we could align the y/u/v planes and adjust stride. 101 picture->y = mem; 102 mem += y_size; 103 104 picture->u = mem; 105 mem += uv_size; 106 picture->v = mem; 107 mem += uv_size; 108 109 if (a_size) { 110 picture->a = mem; 111 mem += a_size; 112 } 113 if (uv0_size) { 114 picture->u0 = mem; 115 mem += uv0_size; 116 picture->v0 = mem; 117 mem += uv0_size; 118 } 119 } else { 120 void* memory; 121 const uint64_t argb_size = (uint64_t)width * height; 122 if (width <= 0 || height <= 0) { 123 return 0; 124 } 125 // Clear previous buffer and allocate a new one. 126 WebPPictureFree(picture); // erase previous buffer 127 memory = WebPSafeMalloc(argb_size, sizeof(*picture->argb)); 128 if (memory == NULL) return 0; 129 130 // TODO(skal): align plane to cache line? 131 picture->memory_argb_ = memory; 132 picture->argb = (uint32_t*)memory; 133 picture->argb_stride = width; 134 } 135 } 136 return 1; 137 } 138 139 // Remove reference to the ARGB buffer (doesn't free anything). 140 static void PictureResetARGB(WebPPicture* const picture) { 141 picture->memory_argb_ = NULL; 142 picture->argb = NULL; 143 picture->argb_stride = 0; 144 } 145 146 // Remove reference to the YUVA buffer (doesn't free anything). 147 static void PictureResetYUVA(WebPPicture* const picture) { 148 picture->memory_ = NULL; 149 picture->y = picture->u = picture->v = picture->a = NULL; 150 picture->u0 = picture->v0 = NULL; 151 picture->y_stride = picture->uv_stride = 0; 152 picture->a_stride = 0; 153 picture->uv0_stride = 0; 154 } 155 156 // Grab the 'specs' (writer, *opaque, width, height...) from 'src' and copy them 157 // into 'dst'. Mark 'dst' as not owning any memory. 158 static void WebPPictureGrabSpecs(const WebPPicture* const src, 159 WebPPicture* const dst) { 160 assert(src != NULL && dst != NULL); 161 *dst = *src; 162 PictureResetYUVA(dst); 163 PictureResetARGB(dst); 164 } 165 166 // Allocate a new argb buffer, discarding any existing one and preserving 167 // the other YUV(A) buffer. 168 static int PictureAllocARGB(WebPPicture* const picture) { 169 WebPPicture tmp; 170 free(picture->memory_argb_); 171 PictureResetARGB(picture); 172 picture->use_argb = 1; 173 WebPPictureGrabSpecs(picture, &tmp); 174 if (!WebPPictureAlloc(&tmp)) { 175 return WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY); 176 } 177 picture->memory_argb_ = tmp.memory_argb_; 178 picture->argb = tmp.argb; 179 picture->argb_stride = tmp.argb_stride; 180 return 1; 181 } 182 183 // Release memory owned by 'picture' (both YUV and ARGB buffers). 184 void WebPPictureFree(WebPPicture* picture) { 185 if (picture != NULL) { 186 free(picture->memory_); 187 free(picture->memory_argb_); 188 PictureResetYUVA(picture); 189 PictureResetARGB(picture); 190 } 191 } 192 193 //------------------------------------------------------------------------------ 194 // Picture copying 195 196 // Not worth moving to dsp/enc.c (only used here). 197 static void CopyPlane(const uint8_t* src, int src_stride, 198 uint8_t* dst, int dst_stride, int width, int height) { 199 while (height-- > 0) { 200 memcpy(dst, src, width); 201 src += src_stride; 202 dst += dst_stride; 203 } 204 } 205 206 // Adjust top-left corner to chroma sample position. 207 static void SnapTopLeftPosition(const WebPPicture* const pic, 208 int* const left, int* const top) { 209 if (!pic->use_argb) { 210 const int is_yuv422 = IS_YUV_CSP(pic->colorspace, WEBP_YUV422); 211 if (IS_YUV_CSP(pic->colorspace, WEBP_YUV420) || is_yuv422) { 212 *left &= ~1; 213 if (!is_yuv422) *top &= ~1; 214 } 215 } 216 } 217 218 // Adjust top-left corner and verify that the sub-rectangle is valid. 219 static int AdjustAndCheckRectangle(const WebPPicture* const pic, 220 int* const left, int* const top, 221 int width, int height) { 222 SnapTopLeftPosition(pic, left, top); 223 if ((*left) < 0 || (*top) < 0) return 0; 224 if (width <= 0 || height <= 0) return 0; 225 if ((*left) + width > pic->width) return 0; 226 if ((*top) + height > pic->height) return 0; 227 return 1; 228 } 229 230 int WebPPictureCopy(const WebPPicture* src, WebPPicture* dst) { 231 if (src == NULL || dst == NULL) return 0; 232 if (src == dst) return 1; 233 234 WebPPictureGrabSpecs(src, dst); 235 if (!WebPPictureAlloc(dst)) return 0; 236 237 if (!src->use_argb) { 238 CopyPlane(src->y, src->y_stride, 239 dst->y, dst->y_stride, dst->width, dst->height); 240 CopyPlane(src->u, src->uv_stride, 241 dst->u, dst->uv_stride, HALVE(dst->width), HALVE(dst->height)); 242 CopyPlane(src->v, src->uv_stride, 243 dst->v, dst->uv_stride, HALVE(dst->width), HALVE(dst->height)); 244 if (dst->a != NULL) { 245 CopyPlane(src->a, src->a_stride, 246 dst->a, dst->a_stride, dst->width, dst->height); 247 } 248 #ifdef WEBP_EXPERIMENTAL_FEATURES 249 if (dst->u0 != NULL) { 250 int uv0_width = src->width; 251 if (IS_YUV_CSP(dst->colorspace, WEBP_YUV422)) { 252 uv0_width = HALVE(uv0_width); 253 } 254 CopyPlane(src->u0, src->uv0_stride, 255 dst->u0, dst->uv0_stride, uv0_width, dst->height); 256 CopyPlane(src->v0, src->uv0_stride, 257 dst->v0, dst->uv0_stride, uv0_width, dst->height); 258 } 259 #endif 260 } else { 261 CopyPlane((const uint8_t*)src->argb, 4 * src->argb_stride, 262 (uint8_t*)dst->argb, 4 * dst->argb_stride, 263 4 * dst->width, dst->height); 264 } 265 return 1; 266 } 267 268 int WebPPictureIsView(const WebPPicture* picture) { 269 if (picture == NULL) return 0; 270 if (picture->use_argb) { 271 return (picture->memory_argb_ == NULL); 272 } 273 return (picture->memory_ == NULL); 274 } 275 276 int WebPPictureView(const WebPPicture* src, 277 int left, int top, int width, int height, 278 WebPPicture* dst) { 279 if (src == NULL || dst == NULL) return 0; 280 281 // verify rectangle position. 282 if (!AdjustAndCheckRectangle(src, &left, &top, width, height)) return 0; 283 284 if (src != dst) { // beware of aliasing! We don't want to leak 'memory_'. 285 WebPPictureGrabSpecs(src, dst); 286 } 287 dst->width = width; 288 dst->height = height; 289 if (!src->use_argb) { 290 dst->y = src->y + top * src->y_stride + left; 291 dst->u = src->u + (top >> 1) * src->uv_stride + (left >> 1); 292 dst->v = src->v + (top >> 1) * src->uv_stride + (left >> 1); 293 if (src->a != NULL) { 294 dst->a = src->a + top * src->a_stride + left; 295 } 296 #ifdef WEBP_EXPERIMENTAL_FEATURES 297 if (src->u0 != NULL) { 298 const int left_pos = 299 IS_YUV_CSP(dst->colorspace, WEBP_YUV422) ? (left >> 1) : left; 300 dst->u0 = src->u0 + top * src->uv0_stride + left_pos; 301 dst->v0 = src->v0 + top * src->uv0_stride + left_pos; 302 } 303 #endif 304 } else { 305 dst->argb = src->argb + top * src->argb_stride + left; 306 } 307 return 1; 308 } 309 310 //------------------------------------------------------------------------------ 311 // Picture cropping 312 313 int WebPPictureCrop(WebPPicture* pic, 314 int left, int top, int width, int height) { 315 WebPPicture tmp; 316 317 if (pic == NULL) return 0; 318 if (!AdjustAndCheckRectangle(pic, &left, &top, width, height)) return 0; 319 320 WebPPictureGrabSpecs(pic, &tmp); 321 tmp.width = width; 322 tmp.height = height; 323 if (!WebPPictureAlloc(&tmp)) return 0; 324 325 if (!pic->use_argb) { 326 const int y_offset = top * pic->y_stride + left; 327 const int uv_offset = (top / 2) * pic->uv_stride + left / 2; 328 CopyPlane(pic->y + y_offset, pic->y_stride, 329 tmp.y, tmp.y_stride, width, height); 330 CopyPlane(pic->u + uv_offset, pic->uv_stride, 331 tmp.u, tmp.uv_stride, HALVE(width), HALVE(height)); 332 CopyPlane(pic->v + uv_offset, pic->uv_stride, 333 tmp.v, tmp.uv_stride, HALVE(width), HALVE(height)); 334 335 if (tmp.a != NULL) { 336 const int a_offset = top * pic->a_stride + left; 337 CopyPlane(pic->a + a_offset, pic->a_stride, 338 tmp.a, tmp.a_stride, width, height); 339 } 340 #ifdef WEBP_EXPERIMENTAL_FEATURES 341 if (tmp.u0 != NULL) { 342 int w = width; 343 int left_pos = left; 344 if (IS_YUV_CSP(tmp.colorspace, WEBP_YUV422)) { 345 w = HALVE(w); 346 left_pos = HALVE(left_pos); 347 } 348 CopyPlane(pic->u0 + top * pic->uv0_stride + left_pos, pic->uv0_stride, 349 tmp.u0, tmp.uv0_stride, w, height); 350 CopyPlane(pic->v0 + top * pic->uv0_stride + left_pos, pic->uv0_stride, 351 tmp.v0, tmp.uv0_stride, w, height); 352 } 353 #endif 354 } else { 355 const uint8_t* const src = 356 (const uint8_t*)(pic->argb + top * pic->argb_stride + left); 357 CopyPlane(src, pic->argb_stride * 4, 358 (uint8_t*)tmp.argb, tmp.argb_stride * 4, 359 width * 4, height); 360 } 361 WebPPictureFree(pic); 362 *pic = tmp; 363 return 1; 364 } 365 366 //------------------------------------------------------------------------------ 367 // Simple picture rescaler 368 369 static void RescalePlane(const uint8_t* src, 370 int src_width, int src_height, int src_stride, 371 uint8_t* dst, 372 int dst_width, int dst_height, int dst_stride, 373 int32_t* const work, 374 int num_channels) { 375 WebPRescaler rescaler; 376 int y = 0; 377 WebPRescalerInit(&rescaler, src_width, src_height, 378 dst, dst_width, dst_height, dst_stride, 379 num_channels, 380 src_width, dst_width, 381 src_height, dst_height, 382 work); 383 memset(work, 0, 2 * dst_width * num_channels * sizeof(*work)); 384 while (y < src_height) { 385 y += WebPRescalerImport(&rescaler, src_height - y, 386 src + y * src_stride, src_stride); 387 WebPRescalerExport(&rescaler); 388 } 389 } 390 391 int WebPPictureRescale(WebPPicture* pic, int width, int height) { 392 WebPPicture tmp; 393 int prev_width, prev_height; 394 int32_t* work; 395 396 if (pic == NULL) return 0; 397 prev_width = pic->width; 398 prev_height = pic->height; 399 // if width is unspecified, scale original proportionally to height ratio. 400 if (width == 0) { 401 width = (prev_width * height + prev_height / 2) / prev_height; 402 } 403 // if height is unspecified, scale original proportionally to width ratio. 404 if (height == 0) { 405 height = (prev_height * width + prev_width / 2) / prev_width; 406 } 407 // Check if the overall dimensions still make sense. 408 if (width <= 0 || height <= 0) return 0; 409 410 WebPPictureGrabSpecs(pic, &tmp); 411 tmp.width = width; 412 tmp.height = height; 413 if (!WebPPictureAlloc(&tmp)) return 0; 414 415 if (!pic->use_argb) { 416 work = (int32_t*)WebPSafeMalloc(2ULL * width, sizeof(*work)); 417 if (work == NULL) { 418 WebPPictureFree(&tmp); 419 return 0; 420 } 421 422 RescalePlane(pic->y, prev_width, prev_height, pic->y_stride, 423 tmp.y, width, height, tmp.y_stride, work, 1); 424 RescalePlane(pic->u, 425 HALVE(prev_width), HALVE(prev_height), pic->uv_stride, 426 tmp.u, 427 HALVE(width), HALVE(height), tmp.uv_stride, work, 1); 428 RescalePlane(pic->v, 429 HALVE(prev_width), HALVE(prev_height), pic->uv_stride, 430 tmp.v, 431 HALVE(width), HALVE(height), tmp.uv_stride, work, 1); 432 433 if (tmp.a != NULL) { 434 RescalePlane(pic->a, prev_width, prev_height, pic->a_stride, 435 tmp.a, width, height, tmp.a_stride, work, 1); 436 } 437 #ifdef WEBP_EXPERIMENTAL_FEATURES 438 if (tmp.u0 != NULL) { 439 const int s = IS_YUV_CSP(tmp.colorspace, WEBP_YUV422) ? 2 : 1; 440 RescalePlane( 441 pic->u0, (prev_width + s / 2) / s, prev_height, pic->uv0_stride, 442 tmp.u0, (width + s / 2) / s, height, tmp.uv0_stride, work, 1); 443 RescalePlane( 444 pic->v0, (prev_width + s / 2) / s, prev_height, pic->uv0_stride, 445 tmp.v0, (width + s / 2) / s, height, tmp.uv0_stride, work, 1); 446 } 447 #endif 448 } else { 449 work = (int32_t*)WebPSafeMalloc(2ULL * width * 4, sizeof(*work)); 450 if (work == NULL) { 451 WebPPictureFree(&tmp); 452 return 0; 453 } 454 455 RescalePlane((const uint8_t*)pic->argb, prev_width, prev_height, 456 pic->argb_stride * 4, 457 (uint8_t*)tmp.argb, width, height, 458 tmp.argb_stride * 4, 459 work, 4); 460 461 } 462 WebPPictureFree(pic); 463 free(work); 464 *pic = tmp; 465 return 1; 466 } 467 468 //------------------------------------------------------------------------------ 469 // WebPMemoryWriter: Write-to-memory 470 471 void WebPMemoryWriterInit(WebPMemoryWriter* writer) { 472 writer->mem = NULL; 473 writer->size = 0; 474 writer->max_size = 0; 475 } 476 477 int WebPMemoryWrite(const uint8_t* data, size_t data_size, 478 const WebPPicture* picture) { 479 WebPMemoryWriter* const w = (WebPMemoryWriter*)picture->custom_ptr; 480 uint64_t next_size; 481 if (w == NULL) { 482 return 1; 483 } 484 next_size = (uint64_t)w->size + data_size; 485 if (next_size > w->max_size) { 486 uint8_t* new_mem; 487 uint64_t next_max_size = 2ULL * w->max_size; 488 if (next_max_size < next_size) next_max_size = next_size; 489 if (next_max_size < 8192ULL) next_max_size = 8192ULL; 490 new_mem = (uint8_t*)WebPSafeMalloc(next_max_size, 1); 491 if (new_mem == NULL) { 492 return 0; 493 } 494 if (w->size > 0) { 495 memcpy(new_mem, w->mem, w->size); 496 } 497 free(w->mem); 498 w->mem = new_mem; 499 // down-cast is ok, thanks to WebPSafeMalloc 500 w->max_size = (size_t)next_max_size; 501 } 502 if (data_size > 0) { 503 memcpy(w->mem + w->size, data, data_size); 504 w->size += data_size; 505 } 506 return 1; 507 } 508 509 //------------------------------------------------------------------------------ 510 // Detection of non-trivial transparency 511 512 // Returns true if alpha[] has non-0xff values. 513 static int CheckNonOpaque(const uint8_t* alpha, int width, int height, 514 int x_step, int y_step) { 515 if (alpha == NULL) return 0; 516 while (height-- > 0) { 517 int x; 518 for (x = 0; x < width * x_step; x += x_step) { 519 if (alpha[x] != 0xff) return 1; // TODO(skal): check 4/8 bytes at a time. 520 } 521 alpha += y_step; 522 } 523 return 0; 524 } 525 526 // Checking for the presence of non-opaque alpha. 527 int WebPPictureHasTransparency(const WebPPicture* picture) { 528 if (picture == NULL) return 0; 529 if (!picture->use_argb) { 530 return CheckNonOpaque(picture->a, picture->width, picture->height, 531 1, picture->a_stride); 532 } else { 533 int x, y; 534 const uint32_t* argb = picture->argb; 535 if (argb == NULL) return 0; 536 for (y = 0; y < picture->height; ++y) { 537 for (x = 0; x < picture->width; ++x) { 538 if (argb[x] < 0xff000000u) return 1; // test any alpha values != 0xff 539 } 540 argb += picture->argb_stride; 541 } 542 } 543 return 0; 544 } 545 546 //------------------------------------------------------------------------------ 547 // RGB -> YUV conversion 548 549 // TODO: we can do better than simply 2x2 averaging on U/V samples. 550 #define SUM4(ptr) ((ptr)[0] + (ptr)[step] + \ 551 (ptr)[rgb_stride] + (ptr)[rgb_stride + step]) 552 #define SUM2H(ptr) (2 * (ptr)[0] + 2 * (ptr)[step]) 553 #define SUM2V(ptr) (2 * (ptr)[0] + 2 * (ptr)[rgb_stride]) 554 #define SUM1(ptr) (4 * (ptr)[0]) 555 #define RGB_TO_UV(x, y, SUM) { \ 556 const int src = (2 * (step * (x) + (y) * rgb_stride)); \ 557 const int dst = (x) + (y) * picture->uv_stride; \ 558 const int r = SUM(r_ptr + src); \ 559 const int g = SUM(g_ptr + src); \ 560 const int b = SUM(b_ptr + src); \ 561 picture->u[dst] = VP8RGBToU(r, g, b); \ 562 picture->v[dst] = VP8RGBToV(r, g, b); \ 563 } 564 565 #define RGB_TO_UV0(x_in, x_out, y, SUM) { \ 566 const int src = (step * (x_in) + (y) * rgb_stride); \ 567 const int dst = (x_out) + (y) * picture->uv0_stride; \ 568 const int r = SUM(r_ptr + src); \ 569 const int g = SUM(g_ptr + src); \ 570 const int b = SUM(b_ptr + src); \ 571 picture->u0[dst] = VP8RGBToU(r, g, b); \ 572 picture->v0[dst] = VP8RGBToV(r, g, b); \ 573 } 574 575 static void MakeGray(WebPPicture* const picture) { 576 int y; 577 const int uv_width = HALVE(picture->width); 578 const int uv_height = HALVE(picture->height); 579 for (y = 0; y < uv_height; ++y) { 580 memset(picture->u + y * picture->uv_stride, 128, uv_width); 581 memset(picture->v + y * picture->uv_stride, 128, uv_width); 582 } 583 } 584 585 static int ImportYUVAFromRGBA(const uint8_t* const r_ptr, 586 const uint8_t* const g_ptr, 587 const uint8_t* const b_ptr, 588 const uint8_t* const a_ptr, 589 int step, // bytes per pixel 590 int rgb_stride, // bytes per scanline 591 WebPPicture* const picture) { 592 const WebPEncCSP uv_csp = picture->colorspace & WEBP_CSP_UV_MASK; 593 int x, y; 594 const int width = picture->width; 595 const int height = picture->height; 596 const int has_alpha = CheckNonOpaque(a_ptr, width, height, step, rgb_stride); 597 598 picture->colorspace = uv_csp; 599 picture->use_argb = 0; 600 if (has_alpha) { 601 picture->colorspace |= WEBP_CSP_ALPHA_BIT; 602 } 603 if (!WebPPictureAlloc(picture)) return 0; 604 605 // Import luma plane 606 for (y = 0; y < height; ++y) { 607 for (x = 0; x < width; ++x) { 608 const int offset = step * x + y * rgb_stride; 609 picture->y[x + y * picture->y_stride] = 610 VP8RGBToY(r_ptr[offset], g_ptr[offset], b_ptr[offset]); 611 } 612 } 613 614 // Downsample U/V plane 615 if (uv_csp != WEBP_YUV400) { 616 for (y = 0; y < (height >> 1); ++y) { 617 for (x = 0; x < (width >> 1); ++x) { 618 RGB_TO_UV(x, y, SUM4); 619 } 620 if (width & 1) { 621 RGB_TO_UV(x, y, SUM2V); 622 } 623 } 624 if (height & 1) { 625 for (x = 0; x < (width >> 1); ++x) { 626 RGB_TO_UV(x, y, SUM2H); 627 } 628 if (width & 1) { 629 RGB_TO_UV(x, y, SUM1); 630 } 631 } 632 633 #ifdef WEBP_EXPERIMENTAL_FEATURES 634 // Store original U/V samples too 635 if (uv_csp == WEBP_YUV422) { 636 for (y = 0; y < height; ++y) { 637 for (x = 0; x < (width >> 1); ++x) { 638 RGB_TO_UV0(2 * x, x, y, SUM2H); 639 } 640 if (width & 1) { 641 RGB_TO_UV0(2 * x, x, y, SUM1); 642 } 643 } 644 } else if (uv_csp == WEBP_YUV444) { 645 for (y = 0; y < height; ++y) { 646 for (x = 0; x < width; ++x) { 647 RGB_TO_UV0(x, x, y, SUM1); 648 } 649 } 650 } 651 #endif 652 } else { 653 MakeGray(picture); 654 } 655 656 if (has_alpha) { 657 assert(step >= 4); 658 for (y = 0; y < height; ++y) { 659 for (x = 0; x < width; ++x) { 660 picture->a[x + y * picture->a_stride] = 661 a_ptr[step * x + y * rgb_stride]; 662 } 663 } 664 } 665 return 1; 666 } 667 668 static int Import(WebPPicture* const picture, 669 const uint8_t* const rgb, int rgb_stride, 670 int step, int swap_rb, int import_alpha) { 671 const uint8_t* const r_ptr = rgb + (swap_rb ? 2 : 0); 672 const uint8_t* const g_ptr = rgb + 1; 673 const uint8_t* const b_ptr = rgb + (swap_rb ? 0 : 2); 674 const uint8_t* const a_ptr = import_alpha ? rgb + 3 : NULL; 675 const int width = picture->width; 676 const int height = picture->height; 677 678 if (!picture->use_argb) { 679 return ImportYUVAFromRGBA(r_ptr, g_ptr, b_ptr, a_ptr, step, rgb_stride, 680 picture); 681 } 682 if (import_alpha) { 683 picture->colorspace |= WEBP_CSP_ALPHA_BIT; 684 } else { 685 picture->colorspace &= ~WEBP_CSP_ALPHA_BIT; 686 } 687 if (!WebPPictureAlloc(picture)) return 0; 688 689 if (!import_alpha) { 690 int x, y; 691 for (y = 0; y < height; ++y) { 692 for (x = 0; x < width; ++x) { 693 const int offset = step * x + y * rgb_stride; 694 const uint32_t argb = 695 0xff000000u | 696 (r_ptr[offset] << 16) | 697 (g_ptr[offset] << 8) | 698 (b_ptr[offset]); 699 picture->argb[x + y * picture->argb_stride] = argb; 700 } 701 } 702 } else { 703 int x, y; 704 assert(step >= 4); 705 for (y = 0; y < height; ++y) { 706 for (x = 0; x < width; ++x) { 707 const int offset = step * x + y * rgb_stride; 708 const uint32_t argb = (a_ptr[offset] << 24) | 709 (r_ptr[offset] << 16) | 710 (g_ptr[offset] << 8) | 711 (b_ptr[offset]); 712 picture->argb[x + y * picture->argb_stride] = argb; 713 } 714 } 715 } 716 return 1; 717 } 718 #undef SUM4 719 #undef SUM2V 720 #undef SUM2H 721 #undef SUM1 722 #undef RGB_TO_UV 723 724 int WebPPictureImportRGB(WebPPicture* picture, 725 const uint8_t* rgb, int rgb_stride) { 726 return Import(picture, rgb, rgb_stride, 3, 0, 0); 727 } 728 729 int WebPPictureImportBGR(WebPPicture* picture, 730 const uint8_t* rgb, int rgb_stride) { 731 return Import(picture, rgb, rgb_stride, 3, 1, 0); 732 } 733 734 int WebPPictureImportRGBA(WebPPicture* picture, 735 const uint8_t* rgba, int rgba_stride) { 736 return Import(picture, rgba, rgba_stride, 4, 0, 1); 737 } 738 739 int WebPPictureImportBGRA(WebPPicture* picture, 740 const uint8_t* rgba, int rgba_stride) { 741 return Import(picture, rgba, rgba_stride, 4, 1, 1); 742 } 743 744 int WebPPictureImportRGBX(WebPPicture* picture, 745 const uint8_t* rgba, int rgba_stride) { 746 return Import(picture, rgba, rgba_stride, 4, 0, 0); 747 } 748 749 int WebPPictureImportBGRX(WebPPicture* picture, 750 const uint8_t* rgba, int rgba_stride) { 751 return Import(picture, rgba, rgba_stride, 4, 1, 0); 752 } 753 754 //------------------------------------------------------------------------------ 755 // Automatic YUV <-> ARGB conversions. 756 757 int WebPPictureYUVAToARGB(WebPPicture* picture) { 758 if (picture == NULL) return 0; 759 if (picture->memory_ == NULL || picture->y == NULL || 760 picture->u == NULL || picture->v == NULL) { 761 return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER); 762 } 763 if ((picture->colorspace & WEBP_CSP_ALPHA_BIT) && picture->a == NULL) { 764 return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER); 765 } 766 if ((picture->colorspace & WEBP_CSP_UV_MASK) != WEBP_YUV420) { 767 return WebPEncodingSetError(picture, VP8_ENC_ERROR_INVALID_CONFIGURATION); 768 } 769 // Allocate a new argb buffer (discarding the previous one). 770 if (!PictureAllocARGB(picture)) return 0; 771 772 // Convert 773 { 774 int y; 775 const int width = picture->width; 776 const int height = picture->height; 777 const int argb_stride = 4 * picture->argb_stride; 778 uint8_t* dst = (uint8_t*)picture->argb; 779 const uint8_t *cur_u = picture->u, *cur_v = picture->v, *cur_y = picture->y; 780 WebPUpsampleLinePairFunc upsample = WebPGetLinePairConverter(ALPHA_IS_LAST); 781 782 // First row, with replicated top samples. 783 upsample(NULL, cur_y, cur_u, cur_v, cur_u, cur_v, NULL, dst, width); 784 cur_y += picture->y_stride; 785 dst += argb_stride; 786 // Center rows. 787 for (y = 1; y + 1 < height; y += 2) { 788 const uint8_t* const top_u = cur_u; 789 const uint8_t* const top_v = cur_v; 790 cur_u += picture->uv_stride; 791 cur_v += picture->uv_stride; 792 upsample(cur_y, cur_y + picture->y_stride, top_u, top_v, cur_u, cur_v, 793 dst, dst + argb_stride, width); 794 cur_y += 2 * picture->y_stride; 795 dst += 2 * argb_stride; 796 } 797 // Last row (if needed), with replicated bottom samples. 798 if (height > 1 && !(height & 1)) { 799 upsample(cur_y, NULL, cur_u, cur_v, cur_u, cur_v, dst, NULL, width); 800 } 801 // Insert alpha values if needed, in replacement for the default 0xff ones. 802 if (picture->colorspace & WEBP_CSP_ALPHA_BIT) { 803 for (y = 0; y < height; ++y) { 804 uint32_t* const dst = picture->argb + y * picture->argb_stride; 805 const uint8_t* const src = picture->a + y * picture->a_stride; 806 int x; 807 for (x = 0; x < width; ++x) { 808 dst[x] = (dst[x] & 0x00ffffffu) | (src[x] << 24); 809 } 810 } 811 } 812 } 813 return 1; 814 } 815 816 int WebPPictureARGBToYUVA(WebPPicture* picture, WebPEncCSP colorspace) { 817 if (picture == NULL) return 0; 818 if (picture->argb == NULL) { 819 return WebPEncodingSetError(picture, VP8_ENC_ERROR_NULL_PARAMETER); 820 } else { 821 const uint8_t* const argb = (const uint8_t*)picture->argb; 822 const uint8_t* const r = ALPHA_IS_LAST ? argb + 2 : argb + 1; 823 const uint8_t* const g = ALPHA_IS_LAST ? argb + 1 : argb + 2; 824 const uint8_t* const b = ALPHA_IS_LAST ? argb + 0 : argb + 3; 825 const uint8_t* const a = ALPHA_IS_LAST ? argb + 3 : argb + 0; 826 // We work on a tmp copy of 'picture', because ImportYUVAFromRGBA() 827 // would be calling WebPPictureFree(picture) otherwise. 828 WebPPicture tmp = *picture; 829 PictureResetARGB(&tmp); // reset ARGB buffer so that it's not free()'d. 830 tmp.use_argb = 0; 831 tmp.colorspace = colorspace & WEBP_CSP_UV_MASK; 832 if (!ImportYUVAFromRGBA(r, g, b, a, 4, 4 * picture->argb_stride, &tmp)) { 833 return WebPEncodingSetError(picture, VP8_ENC_ERROR_OUT_OF_MEMORY); 834 } 835 // Copy back the YUV specs into 'picture'. 836 tmp.argb = picture->argb; 837 tmp.argb_stride = picture->argb_stride; 838 tmp.memory_argb_ = picture->memory_argb_; 839 *picture = tmp; 840 } 841 return 1; 842 } 843 844 //------------------------------------------------------------------------------ 845 // Helper: clean up fully transparent area to help compressibility. 846 847 #define SIZE 8 848 #define SIZE2 (SIZE / 2) 849 static int is_transparent_area(const uint8_t* ptr, int stride, int size) { 850 int y, x; 851 for (y = 0; y < size; ++y) { 852 for (x = 0; x < size; ++x) { 853 if (ptr[x]) { 854 return 0; 855 } 856 } 857 ptr += stride; 858 } 859 return 1; 860 } 861 862 static WEBP_INLINE void flatten(uint8_t* ptr, int v, int stride, int size) { 863 int y; 864 for (y = 0; y < size; ++y) { 865 memset(ptr, v, size); 866 ptr += stride; 867 } 868 } 869 870 void WebPCleanupTransparentArea(WebPPicture* pic) { 871 int x, y, w, h; 872 const uint8_t* a_ptr; 873 int values[3] = { 0 }; 874 875 if (pic == NULL) return; 876 877 a_ptr = pic->a; 878 if (a_ptr == NULL) return; // nothing to do 879 880 w = pic->width / SIZE; 881 h = pic->height / SIZE; 882 for (y = 0; y < h; ++y) { 883 int need_reset = 1; 884 for (x = 0; x < w; ++x) { 885 const int off_a = (y * pic->a_stride + x) * SIZE; 886 const int off_y = (y * pic->y_stride + x) * SIZE; 887 const int off_uv = (y * pic->uv_stride + x) * SIZE2; 888 if (is_transparent_area(a_ptr + off_a, pic->a_stride, SIZE)) { 889 if (need_reset) { 890 values[0] = pic->y[off_y]; 891 values[1] = pic->u[off_uv]; 892 values[2] = pic->v[off_uv]; 893 need_reset = 0; 894 } 895 flatten(pic->y + off_y, values[0], pic->y_stride, SIZE); 896 flatten(pic->u + off_uv, values[1], pic->uv_stride, SIZE2); 897 flatten(pic->v + off_uv, values[2], pic->uv_stride, SIZE2); 898 } else { 899 need_reset = 1; 900 } 901 } 902 // ignore the left-overs on right/bottom 903 } 904 } 905 906 #undef SIZE 907 #undef SIZE2 908 909 910 //------------------------------------------------------------------------------ 911 // Distortion 912 913 // Max value returned in case of exact similarity. 914 static const double kMinDistortion_dB = 99.; 915 916 int WebPPictureDistortion(const WebPPicture* pic1, const WebPPicture* pic2, 917 int type, float result[5]) { 918 int c; 919 DistoStats stats[5]; 920 int has_alpha; 921 922 if (pic1 == NULL || pic2 == NULL || 923 pic1->width != pic2->width || pic1->height != pic2->height || 924 pic1->y == NULL || pic2->y == NULL || 925 pic1->u == NULL || pic2->u == NULL || 926 pic1->v == NULL || pic2->v == NULL || 927 result == NULL) { 928 return 0; 929 } 930 // TODO(skal): provide distortion for ARGB too. 931 if (pic1->use_argb == 1 || pic1->use_argb != pic2->use_argb) { 932 return 0; 933 } 934 935 has_alpha = !!(pic1->colorspace & WEBP_CSP_ALPHA_BIT); 936 if (has_alpha != !!(pic2->colorspace & WEBP_CSP_ALPHA_BIT) || 937 (has_alpha && (pic1->a == NULL || pic2->a == NULL))) { 938 return 0; 939 } 940 941 memset(stats, 0, sizeof(stats)); 942 VP8SSIMAccumulatePlane(pic1->y, pic1->y_stride, 943 pic2->y, pic2->y_stride, 944 pic1->width, pic1->height, &stats[0]); 945 VP8SSIMAccumulatePlane(pic1->u, pic1->uv_stride, 946 pic2->u, pic2->uv_stride, 947 (pic1->width + 1) >> 1, (pic1->height + 1) >> 1, 948 &stats[1]); 949 VP8SSIMAccumulatePlane(pic1->v, pic1->uv_stride, 950 pic2->v, pic2->uv_stride, 951 (pic1->width + 1) >> 1, (pic1->height + 1) >> 1, 952 &stats[2]); 953 if (has_alpha) { 954 VP8SSIMAccumulatePlane(pic1->a, pic1->a_stride, 955 pic2->a, pic2->a_stride, 956 pic1->width, pic1->height, &stats[3]); 957 } 958 for (c = 0; c <= 4; ++c) { 959 if (type == 1) { 960 const double v = VP8SSIMGet(&stats[c]); 961 result[c] = (float)((v < 1.) ? -10.0 * log10(1. - v) 962 : kMinDistortion_dB); 963 } else { 964 const double v = VP8SSIMGetSquaredError(&stats[c]); 965 result[c] = (float)((v > 0.) ? -4.3429448 * log(v / (255 * 255.)) 966 : kMinDistortion_dB); 967 } 968 // Accumulate forward 969 if (c < 4) VP8SSIMAddStats(&stats[c], &stats[4]); 970 } 971 return 1; 972 } 973 974 //------------------------------------------------------------------------------ 975 // Simplest high-level calls: 976 977 typedef int (*Importer)(WebPPicture* const, const uint8_t* const, int); 978 979 static size_t Encode(const uint8_t* rgba, int width, int height, int stride, 980 Importer import, float quality_factor, int lossless, 981 uint8_t** output) { 982 WebPPicture pic; 983 WebPConfig config; 984 WebPMemoryWriter wrt; 985 int ok; 986 987 if (!WebPConfigPreset(&config, WEBP_PRESET_DEFAULT, quality_factor) || 988 !WebPPictureInit(&pic)) { 989 return 0; // shouldn't happen, except if system installation is broken 990 } 991 992 config.lossless = !!lossless; 993 pic.use_argb = !!lossless; 994 pic.width = width; 995 pic.height = height; 996 pic.writer = WebPMemoryWrite; 997 pic.custom_ptr = &wrt; 998 WebPMemoryWriterInit(&wrt); 999 1000 ok = import(&pic, rgba, stride) && WebPEncode(&config, &pic); 1001 WebPPictureFree(&pic); 1002 if (!ok) { 1003 free(wrt.mem); 1004 *output = NULL; 1005 return 0; 1006 } 1007 *output = wrt.mem; 1008 return wrt.size; 1009 } 1010 1011 #define ENCODE_FUNC(NAME, IMPORTER) \ 1012 size_t NAME(const uint8_t* in, int w, int h, int bps, float q, \ 1013 uint8_t** out) { \ 1014 return Encode(in, w, h, bps, IMPORTER, q, 0, out); \ 1015 } 1016 1017 ENCODE_FUNC(WebPEncodeRGB, WebPPictureImportRGB); 1018 ENCODE_FUNC(WebPEncodeBGR, WebPPictureImportBGR); 1019 ENCODE_FUNC(WebPEncodeRGBA, WebPPictureImportRGBA); 1020 ENCODE_FUNC(WebPEncodeBGRA, WebPPictureImportBGRA); 1021 1022 #undef ENCODE_FUNC 1023 1024 #define LOSSLESS_DEFAULT_QUALITY 70. 1025 #define LOSSLESS_ENCODE_FUNC(NAME, IMPORTER) \ 1026 size_t NAME(const uint8_t* in, int w, int h, int bps, uint8_t** out) { \ 1027 return Encode(in, w, h, bps, IMPORTER, LOSSLESS_DEFAULT_QUALITY, 1, out); \ 1028 } 1029 1030 LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessRGB, WebPPictureImportRGB); 1031 LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessBGR, WebPPictureImportBGR); 1032 LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessRGBA, WebPPictureImportRGBA); 1033 LOSSLESS_ENCODE_FUNC(WebPEncodeLosslessBGRA, WebPPictureImportBGRA); 1034 1035 #undef LOSSLESS_ENCODE_FUNC 1036 1037 //------------------------------------------------------------------------------ 1038 1039 #if defined(__cplusplus) || defined(c_plusplus) 1040 } // extern "C" 1041 #endif 1042
