1// Copyright 2011 Google Inc. All Rights Reserved. 2// 3// Use of this source code is governed by a BSD-style license 4// that can be found in the COPYING file in the root of the source 5// tree. An additional intellectual property rights grant can be found 6// in the file PATENTS. All contributing project authors may 7// be found in the AUTHORS file in the root of the source tree. 8// ----------------------------------------------------------------------------- 9// 10// Speed-critical functions. 11// 12// Author: Skal (pascal.massimino@gmail.com) 13 14#ifndef WEBP_DSP_DSP_H_ 15#define WEBP_DSP_DSP_H_ 16 17#ifdef HAVE_CONFIG_H 18#include "src/webp/config.h" 19#endif 20 21#include "src/webp/types.h" 22 23#ifdef __cplusplus 24extern "C" { 25#endif 26 27#define BPS 32 // this is the common stride for enc/dec 28 29//------------------------------------------------------------------------------ 30// CPU detection 31 32#if defined(__GNUC__) 33# define LOCAL_GCC_VERSION ((__GNUC__ << 8) | __GNUC_MINOR__) 34# define LOCAL_GCC_PREREQ(maj, min) \ 35 (LOCAL_GCC_VERSION >= (((maj) << 8) | (min))) 36#else 37# define LOCAL_GCC_VERSION 0 38# define LOCAL_GCC_PREREQ(maj, min) 0 39#endif 40 41#if defined(__clang__) 42# define LOCAL_CLANG_VERSION ((__clang_major__ << 8) | __clang_minor__) 43# define LOCAL_CLANG_PREREQ(maj, min) \ 44 (LOCAL_CLANG_VERSION >= (((maj) << 8) | (min))) 45#else 46# define LOCAL_CLANG_VERSION 0 47# define LOCAL_CLANG_PREREQ(maj, min) 0 48#endif 49 50#ifndef __has_builtin 51# define __has_builtin(x) 0 52#endif 53 54// for now, none of the optimizations below are available in emscripten 55#if !defined(EMSCRIPTEN) 56 57#if defined(_MSC_VER) && _MSC_VER > 1310 && \ 58 (defined(_M_X64) || defined(_M_IX86)) 59#define WEBP_MSC_SSE2 // Visual C++ SSE2 targets 60#endif 61 62#if defined(_MSC_VER) && _MSC_VER >= 1500 && \ 63 (defined(_M_X64) || defined(_M_IX86)) 64#define WEBP_MSC_SSE41 // Visual C++ SSE4.1 targets 65#endif 66 67// WEBP_HAVE_* are used to indicate the presence of the instruction set in dsp 68// files without intrinsics, allowing the corresponding Init() to be called. 69// Files containing intrinsics will need to be built targeting the instruction 70// set so should succeed on one of the earlier tests. 71#if defined(__SSE2__) || defined(WEBP_MSC_SSE2) || defined(WEBP_HAVE_SSE2) 72#define WEBP_USE_SSE2 73#endif 74 75#if defined(__SSE4_1__) || defined(WEBP_MSC_SSE41) || defined(WEBP_HAVE_SSE41) 76#define WEBP_USE_SSE41 77#endif 78 79#if defined(__AVX2__) || defined(WEBP_HAVE_AVX2) 80#define WEBP_USE_AVX2 81#endif 82 83// The intrinsics currently cause compiler errors with arm-nacl-gcc and the 84// inline assembly would need to be modified for use with Native Client. 85#if (defined(__ARM_NEON__) || \ 86 defined(__aarch64__) || defined(WEBP_HAVE_NEON)) && \ 87 !defined(__native_client__) 88#define WEBP_USE_NEON 89#endif 90 91#if !defined(WEBP_USE_NEON) && defined(__ANDROID__) && \ 92 defined(__ARM_ARCH_7A__) && defined(HAVE_CPU_FEATURES_H) 93#define WEBP_ANDROID_NEON // Android targets that may have NEON 94#define WEBP_USE_NEON 95#endif 96 97#if defined(_MSC_VER) && _MSC_VER >= 1700 && defined(_M_ARM) 98#define WEBP_USE_NEON 99#define WEBP_USE_INTRINSICS 100#endif 101 102#if defined(__mips__) && !defined(__mips64) && \ 103 defined(__mips_isa_rev) && (__mips_isa_rev >= 1) && (__mips_isa_rev < 6) 104#define WEBP_USE_MIPS32 105#if (__mips_isa_rev >= 2) 106#define WEBP_USE_MIPS32_R2 107#if defined(__mips_dspr2) || (defined(__mips_dsp_rev) && __mips_dsp_rev >= 2) 108#define WEBP_USE_MIPS_DSP_R2 109#endif 110#endif 111#endif 112 113#if defined(__mips_msa) && defined(__mips_isa_rev) && (__mips_isa_rev >= 5) 114#define WEBP_USE_MSA 115#endif 116 117#endif /* EMSCRIPTEN */ 118 119#ifndef WEBP_DSP_OMIT_C_CODE 120#define WEBP_DSP_OMIT_C_CODE 1 121#endif 122 123#if (defined(__aarch64__) || defined(__ARM_NEON__)) && WEBP_DSP_OMIT_C_CODE 124#define WEBP_NEON_OMIT_C_CODE 1 125#else 126#define WEBP_NEON_OMIT_C_CODE 0 127#endif 128 129#if !(LOCAL_CLANG_PREREQ(3,8) || LOCAL_GCC_PREREQ(4,8) || defined(__aarch64__)) 130#define WEBP_NEON_WORK_AROUND_GCC 1 131#else 132#define WEBP_NEON_WORK_AROUND_GCC 0 133#endif 134 135// This macro prevents thread_sanitizer from reporting known concurrent writes. 136#define WEBP_TSAN_IGNORE_FUNCTION 137#if defined(__has_feature) 138#if __has_feature(thread_sanitizer) 139#undef WEBP_TSAN_IGNORE_FUNCTION 140#define WEBP_TSAN_IGNORE_FUNCTION __attribute__((no_sanitize_thread)) 141#endif 142#endif 143 144#define WEBP_UBSAN_IGNORE_UNDEF 145#define WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW 146#if defined(__clang__) && defined(__has_attribute) 147#if __has_attribute(no_sanitize) 148// This macro prevents the undefined behavior sanitizer from reporting 149// failures. This is only meant to silence unaligned loads on platforms that 150// are known to support them. 151#undef WEBP_UBSAN_IGNORE_UNDEF 152#define WEBP_UBSAN_IGNORE_UNDEF \ 153 __attribute__((no_sanitize("undefined"))) 154 155// This macro prevents the undefined behavior sanitizer from reporting 156// failures related to unsigned integer overflows. This is only meant to 157// silence cases where this well defined behavior is expected. 158#undef WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW 159#define WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW \ 160 __attribute__((no_sanitize("unsigned-integer-overflow"))) 161#endif 162#endif 163 164// Regularize the definition of WEBP_SWAP_16BIT_CSP (backward compatibility) 165#if !defined(WEBP_SWAP_16BIT_CSP) 166#define WEBP_SWAP_16BIT_CSP 0 167#endif 168 169typedef enum { 170 kSSE2, 171 kSSE3, 172 kSlowSSSE3, // special feature for slow SSSE3 architectures 173 kSSE4_1, 174 kAVX, 175 kAVX2, 176 kNEON, 177 kMIPS32, 178 kMIPSdspR2, 179 kMSA 180} CPUFeature; 181// returns true if the CPU supports the feature. 182typedef int (*VP8CPUInfo)(CPUFeature feature); 183WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo; 184 185//------------------------------------------------------------------------------ 186// Init stub generator 187 188// Defines an init function stub to ensure each module exposes a symbol, 189// avoiding a compiler warning. 190#define WEBP_DSP_INIT_STUB(func) \ 191 extern void func(void); \ 192 WEBP_TSAN_IGNORE_FUNCTION void func(void) {} 193 194//------------------------------------------------------------------------------ 195// Encoding 196 197// Transforms 198// VP8Idct: Does one of two inverse transforms. If do_two is set, the transforms 199// will be done for (ref, in, dst) and (ref + 4, in + 16, dst + 4). 200typedef void (*VP8Idct)(const uint8_t* ref, const int16_t* in, uint8_t* dst, 201 int do_two); 202typedef void (*VP8Fdct)(const uint8_t* src, const uint8_t* ref, int16_t* out); 203typedef void (*VP8WHT)(const int16_t* in, int16_t* out); 204extern VP8Idct VP8ITransform; 205extern VP8Fdct VP8FTransform; 206extern VP8Fdct VP8FTransform2; // performs two transforms at a time 207extern VP8WHT VP8FTransformWHT; 208// Predictions 209// *dst is the destination block. *top and *left can be NULL. 210typedef void (*VP8IntraPreds)(uint8_t *dst, const uint8_t* left, 211 const uint8_t* top); 212typedef void (*VP8Intra4Preds)(uint8_t *dst, const uint8_t* top); 213extern VP8Intra4Preds VP8EncPredLuma4; 214extern VP8IntraPreds VP8EncPredLuma16; 215extern VP8IntraPreds VP8EncPredChroma8; 216 217typedef int (*VP8Metric)(const uint8_t* pix, const uint8_t* ref); 218extern VP8Metric VP8SSE16x16, VP8SSE16x8, VP8SSE8x8, VP8SSE4x4; 219typedef int (*VP8WMetric)(const uint8_t* pix, const uint8_t* ref, 220 const uint16_t* const weights); 221// The weights for VP8TDisto4x4 and VP8TDisto16x16 contain a row-major 222// 4 by 4 symmetric matrix. 223extern VP8WMetric VP8TDisto4x4, VP8TDisto16x16; 224 225// Compute the average (DC) of four 4x4 blocks. 226// Each sub-4x4 block #i sum is stored in dc[i]. 227typedef void (*VP8MeanMetric)(const uint8_t* ref, uint32_t dc[4]); 228extern VP8MeanMetric VP8Mean16x4; 229 230typedef void (*VP8BlockCopy)(const uint8_t* src, uint8_t* dst); 231extern VP8BlockCopy VP8Copy4x4; 232extern VP8BlockCopy VP8Copy16x8; 233// Quantization 234struct VP8Matrix; // forward declaration 235typedef int (*VP8QuantizeBlock)(int16_t in[16], int16_t out[16], 236 const struct VP8Matrix* const mtx); 237// Same as VP8QuantizeBlock, but quantizes two consecutive blocks. 238typedef int (*VP8Quantize2Blocks)(int16_t in[32], int16_t out[32], 239 const struct VP8Matrix* const mtx); 240 241extern VP8QuantizeBlock VP8EncQuantizeBlock; 242extern VP8Quantize2Blocks VP8EncQuantize2Blocks; 243 244// specific to 2nd transform: 245typedef int (*VP8QuantizeBlockWHT)(int16_t in[16], int16_t out[16], 246 const struct VP8Matrix* const mtx); 247extern VP8QuantizeBlockWHT VP8EncQuantizeBlockWHT; 248 249extern const int VP8DspScan[16 + 4 + 4]; 250 251// Collect histogram for susceptibility calculation. 252#define MAX_COEFF_THRESH 31 // size of histogram used by CollectHistogram. 253typedef struct { 254 // We only need to store max_value and last_non_zero, not the distribution. 255 int max_value; 256 int last_non_zero; 257} VP8Histogram; 258typedef void (*VP8CHisto)(const uint8_t* ref, const uint8_t* pred, 259 int start_block, int end_block, 260 VP8Histogram* const histo); 261extern VP8CHisto VP8CollectHistogram; 262// General-purpose util function to help VP8CollectHistogram(). 263void VP8SetHistogramData(const int distribution[MAX_COEFF_THRESH + 1], 264 VP8Histogram* const histo); 265 266// must be called before using any of the above 267void VP8EncDspInit(void); 268 269//------------------------------------------------------------------------------ 270// cost functions (encoding) 271 272extern const uint16_t VP8EntropyCost[256]; // 8bit fixed-point log(p) 273// approximate cost per level: 274extern const uint16_t VP8LevelFixedCosts[2047 /*MAX_LEVEL*/ + 1]; 275extern const uint8_t VP8EncBands[16 + 1]; 276 277struct VP8Residual; 278typedef void (*VP8SetResidualCoeffsFunc)(const int16_t* const coeffs, 279 struct VP8Residual* const res); 280extern VP8SetResidualCoeffsFunc VP8SetResidualCoeffs; 281 282// Cost calculation function. 283typedef int (*VP8GetResidualCostFunc)(int ctx0, 284 const struct VP8Residual* const res); 285extern VP8GetResidualCostFunc VP8GetResidualCost; 286 287// must be called before anything using the above 288void VP8EncDspCostInit(void); 289 290//------------------------------------------------------------------------------ 291// SSIM / PSNR utils 292 293// struct for accumulating statistical moments 294typedef struct { 295 uint32_t w; // sum(w_i) : sum of weights 296 uint32_t xm, ym; // sum(w_i * x_i), sum(w_i * y_i) 297 uint32_t xxm, xym, yym; // sum(w_i * x_i * x_i), etc. 298} VP8DistoStats; 299 300// Compute the final SSIM value 301// The non-clipped version assumes stats->w = (2 * VP8_SSIM_KERNEL + 1)^2. 302double VP8SSIMFromStats(const VP8DistoStats* const stats); 303double VP8SSIMFromStatsClipped(const VP8DistoStats* const stats); 304 305#define VP8_SSIM_KERNEL 3 // total size of the kernel: 2 * VP8_SSIM_KERNEL + 1 306typedef double (*VP8SSIMGetClippedFunc)(const uint8_t* src1, int stride1, 307 const uint8_t* src2, int stride2, 308 int xo, int yo, // center position 309 int W, int H); // plane dimension 310 311#if !defined(WEBP_REDUCE_SIZE) 312// This version is called with the guarantee that you can load 8 bytes and 313// 8 rows at offset src1 and src2 314typedef double (*VP8SSIMGetFunc)(const uint8_t* src1, int stride1, 315 const uint8_t* src2, int stride2); 316 317extern VP8SSIMGetFunc VP8SSIMGet; // unclipped / unchecked 318extern VP8SSIMGetClippedFunc VP8SSIMGetClipped; // with clipping 319#endif 320 321#if !defined(WEBP_DISABLE_STATS) 322typedef uint32_t (*VP8AccumulateSSEFunc)(const uint8_t* src1, 323 const uint8_t* src2, int len); 324extern VP8AccumulateSSEFunc VP8AccumulateSSE; 325#endif 326 327// must be called before using any of the above directly 328void VP8SSIMDspInit(void); 329 330//------------------------------------------------------------------------------ 331// Decoding 332 333typedef void (*VP8DecIdct)(const int16_t* coeffs, uint8_t* dst); 334// when doing two transforms, coeffs is actually int16_t[2][16]. 335typedef void (*VP8DecIdct2)(const int16_t* coeffs, uint8_t* dst, int do_two); 336extern VP8DecIdct2 VP8Transform; 337extern VP8DecIdct VP8TransformAC3; 338extern VP8DecIdct VP8TransformUV; 339extern VP8DecIdct VP8TransformDC; 340extern VP8DecIdct VP8TransformDCUV; 341extern VP8WHT VP8TransformWHT; 342 343// *dst is the destination block, with stride BPS. Boundary samples are 344// assumed accessible when needed. 345typedef void (*VP8PredFunc)(uint8_t* dst); 346extern VP8PredFunc VP8PredLuma16[/* NUM_B_DC_MODES */]; 347extern VP8PredFunc VP8PredChroma8[/* NUM_B_DC_MODES */]; 348extern VP8PredFunc VP8PredLuma4[/* NUM_BMODES */]; 349 350// clipping tables (for filtering) 351extern const int8_t* const VP8ksclip1; // clips [-1020, 1020] to [-128, 127] 352extern const int8_t* const VP8ksclip2; // clips [-112, 112] to [-16, 15] 353extern const uint8_t* const VP8kclip1; // clips [-255,511] to [0,255] 354extern const uint8_t* const VP8kabs0; // abs(x) for x in [-255,255] 355// must be called first 356void VP8InitClipTables(void); 357 358// simple filter (only for luma) 359typedef void (*VP8SimpleFilterFunc)(uint8_t* p, int stride, int thresh); 360extern VP8SimpleFilterFunc VP8SimpleVFilter16; 361extern VP8SimpleFilterFunc VP8SimpleHFilter16; 362extern VP8SimpleFilterFunc VP8SimpleVFilter16i; // filter 3 inner edges 363extern VP8SimpleFilterFunc VP8SimpleHFilter16i; 364 365// regular filter (on both macroblock edges and inner edges) 366typedef void (*VP8LumaFilterFunc)(uint8_t* luma, int stride, 367 int thresh, int ithresh, int hev_t); 368typedef void (*VP8ChromaFilterFunc)(uint8_t* u, uint8_t* v, int stride, 369 int thresh, int ithresh, int hev_t); 370// on outer edge 371extern VP8LumaFilterFunc VP8VFilter16; 372extern VP8LumaFilterFunc VP8HFilter16; 373extern VP8ChromaFilterFunc VP8VFilter8; 374extern VP8ChromaFilterFunc VP8HFilter8; 375 376// on inner edge 377extern VP8LumaFilterFunc VP8VFilter16i; // filtering 3 inner edges altogether 378extern VP8LumaFilterFunc VP8HFilter16i; 379extern VP8ChromaFilterFunc VP8VFilter8i; // filtering u and v altogether 380extern VP8ChromaFilterFunc VP8HFilter8i; 381 382// Dithering. Combines dithering values (centered around 128) with dst[], 383// according to: dst[] = clip(dst[] + (((dither[]-128) + 8) >> 4) 384#define VP8_DITHER_DESCALE 4 385#define VP8_DITHER_DESCALE_ROUNDER (1 << (VP8_DITHER_DESCALE - 1)) 386#define VP8_DITHER_AMP_BITS 7 387#define VP8_DITHER_AMP_CENTER (1 << VP8_DITHER_AMP_BITS) 388extern void (*VP8DitherCombine8x8)(const uint8_t* dither, uint8_t* dst, 389 int dst_stride); 390 391// must be called before anything using the above 392void VP8DspInit(void); 393 394//------------------------------------------------------------------------------ 395// WebP I/O 396 397#define FANCY_UPSAMPLING // undefined to remove fancy upsampling support 398 399// Convert a pair of y/u/v lines together to the output rgb/a colorspace. 400// bottom_y can be NULL if only one line of output is needed (at top/bottom). 401typedef void (*WebPUpsampleLinePairFunc)( 402 const uint8_t* top_y, const uint8_t* bottom_y, 403 const uint8_t* top_u, const uint8_t* top_v, 404 const uint8_t* cur_u, const uint8_t* cur_v, 405 uint8_t* top_dst, uint8_t* bottom_dst, int len); 406 407#ifdef FANCY_UPSAMPLING 408 409// Fancy upsampling functions to convert YUV to RGB(A) modes 410extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */]; 411 412#endif // FANCY_UPSAMPLING 413 414// Per-row point-sampling methods. 415typedef void (*WebPSamplerRowFunc)(const uint8_t* y, 416 const uint8_t* u, const uint8_t* v, 417 uint8_t* dst, int len); 418// Generic function to apply 'WebPSamplerRowFunc' to the whole plane: 419void WebPSamplerProcessPlane(const uint8_t* y, int y_stride, 420 const uint8_t* u, const uint8_t* v, int uv_stride, 421 uint8_t* dst, int dst_stride, 422 int width, int height, WebPSamplerRowFunc func); 423 424// Sampling functions to convert rows of YUV to RGB(A) 425extern WebPSamplerRowFunc WebPSamplers[/* MODE_LAST */]; 426 427// General function for converting two lines of ARGB or RGBA. 428// 'alpha_is_last' should be true if 0xff000000 is stored in memory as 429// as 0x00, 0x00, 0x00, 0xff (little endian). 430WebPUpsampleLinePairFunc WebPGetLinePairConverter(int alpha_is_last); 431 432// YUV444->RGB converters 433typedef void (*WebPYUV444Converter)(const uint8_t* y, 434 const uint8_t* u, const uint8_t* v, 435 uint8_t* dst, int len); 436 437extern WebPYUV444Converter WebPYUV444Converters[/* MODE_LAST */]; 438 439// Must be called before using the WebPUpsamplers[] (and for premultiplied 440// colorspaces like rgbA, rgbA4444, etc) 441void WebPInitUpsamplers(void); 442// Must be called before using WebPSamplers[] 443void WebPInitSamplers(void); 444// Must be called before using WebPYUV444Converters[] 445void WebPInitYUV444Converters(void); 446 447//------------------------------------------------------------------------------ 448// ARGB -> YUV converters 449 450// Convert ARGB samples to luma Y. 451extern void (*WebPConvertARGBToY)(const uint32_t* argb, uint8_t* y, int width); 452// Convert ARGB samples to U/V with downsampling. do_store should be '1' for 453// even lines and '0' for odd ones. 'src_width' is the original width, not 454// the U/V one. 455extern void (*WebPConvertARGBToUV)(const uint32_t* argb, uint8_t* u, uint8_t* v, 456 int src_width, int do_store); 457 458// Convert a row of accumulated (four-values) of rgba32 toward U/V 459extern void (*WebPConvertRGBA32ToUV)(const uint16_t* rgb, 460 uint8_t* u, uint8_t* v, int width); 461 462// Convert RGB or BGR to Y 463extern void (*WebPConvertRGB24ToY)(const uint8_t* rgb, uint8_t* y, int width); 464extern void (*WebPConvertBGR24ToY)(const uint8_t* bgr, uint8_t* y, int width); 465 466// used for plain-C fallback. 467extern void WebPConvertARGBToUV_C(const uint32_t* argb, uint8_t* u, uint8_t* v, 468 int src_width, int do_store); 469extern void WebPConvertRGBA32ToUV_C(const uint16_t* rgb, 470 uint8_t* u, uint8_t* v, int width); 471 472// utilities for accurate RGB->YUV conversion 473extern uint64_t (*WebPSharpYUVUpdateY)(const uint16_t* src, const uint16_t* ref, 474 uint16_t* dst, int len); 475extern void (*WebPSharpYUVUpdateRGB)(const int16_t* src, const int16_t* ref, 476 int16_t* dst, int len); 477extern void (*WebPSharpYUVFilterRow)(const int16_t* A, const int16_t* B, 478 int len, 479 const uint16_t* best_y, uint16_t* out); 480 481// Must be called before using the above. 482void WebPInitConvertARGBToYUV(void); 483 484//------------------------------------------------------------------------------ 485// Rescaler 486 487struct WebPRescaler; 488 489// Import a row of data and save its contribution in the rescaler. 490// 'channel' denotes the channel number to be imported. 'Expand' corresponds to 491// the wrk->x_expand case. Otherwise, 'Shrink' is to be used. 492typedef void (*WebPRescalerImportRowFunc)(struct WebPRescaler* const wrk, 493 const uint8_t* src); 494 495extern WebPRescalerImportRowFunc WebPRescalerImportRowExpand; 496extern WebPRescalerImportRowFunc WebPRescalerImportRowShrink; 497 498// Export one row (starting at x_out position) from rescaler. 499// 'Expand' corresponds to the wrk->y_expand case. 500// Otherwise 'Shrink' is to be used 501typedef void (*WebPRescalerExportRowFunc)(struct WebPRescaler* const wrk); 502extern WebPRescalerExportRowFunc WebPRescalerExportRowExpand; 503extern WebPRescalerExportRowFunc WebPRescalerExportRowShrink; 504 505// Plain-C implementation, as fall-back. 506extern void WebPRescalerImportRowExpand_C(struct WebPRescaler* const wrk, 507 const uint8_t* src); 508extern void WebPRescalerImportRowShrink_C(struct WebPRescaler* const wrk, 509 const uint8_t* src); 510extern void WebPRescalerExportRowExpand_C(struct WebPRescaler* const wrk); 511extern void WebPRescalerExportRowShrink_C(struct WebPRescaler* const wrk); 512 513// Main entry calls: 514extern void WebPRescalerImportRow(struct WebPRescaler* const wrk, 515 const uint8_t* src); 516// Export one row (starting at x_out position) from rescaler. 517extern void WebPRescalerExportRow(struct WebPRescaler* const wrk); 518 519// Must be called first before using the above. 520void WebPRescalerDspInit(void); 521 522//------------------------------------------------------------------------------ 523// Utilities for processing transparent channel. 524 525// Apply alpha pre-multiply on an rgba, bgra or argb plane of size w * h. 526// alpha_first should be 0 for argb, 1 for rgba or bgra (where alpha is last). 527extern void (*WebPApplyAlphaMultiply)( 528 uint8_t* rgba, int alpha_first, int w, int h, int stride); 529 530// Same, buf specifically for RGBA4444 format 531extern void (*WebPApplyAlphaMultiply4444)( 532 uint8_t* rgba4444, int w, int h, int stride); 533 534// Dispatch the values from alpha[] plane to the ARGB destination 'dst'. 535// Returns true if alpha[] plane has non-trivial values different from 0xff. 536extern int (*WebPDispatchAlpha)(const uint8_t* alpha, int alpha_stride, 537 int width, int height, 538 uint8_t* dst, int dst_stride); 539 540// Transfer packed 8b alpha[] values to green channel in dst[], zero'ing the 541// A/R/B values. 'dst_stride' is the stride for dst[] in uint32_t units. 542extern void (*WebPDispatchAlphaToGreen)(const uint8_t* alpha, int alpha_stride, 543 int width, int height, 544 uint32_t* dst, int dst_stride); 545 546// Extract the alpha values from 32b values in argb[] and pack them into alpha[] 547// (this is the opposite of WebPDispatchAlpha). 548// Returns true if there's only trivial 0xff alpha values. 549extern int (*WebPExtractAlpha)(const uint8_t* argb, int argb_stride, 550 int width, int height, 551 uint8_t* alpha, int alpha_stride); 552 553// Extract the green values from 32b values in argb[] and pack them into alpha[] 554// (this is the opposite of WebPDispatchAlphaToGreen). 555extern void (*WebPExtractGreen)(const uint32_t* argb, uint8_t* alpha, int size); 556 557// Pre-Multiply operation transforms x into x * A / 255 (where x=Y,R,G or B). 558// Un-Multiply operation transforms x into x * 255 / A. 559 560// Pre-Multiply or Un-Multiply (if 'inverse' is true) argb values in a row. 561extern void (*WebPMultARGBRow)(uint32_t* const ptr, int width, int inverse); 562 563// Same a WebPMultARGBRow(), but for several rows. 564void WebPMultARGBRows(uint8_t* ptr, int stride, int width, int num_rows, 565 int inverse); 566 567// Same for a row of single values, with side alpha values. 568extern void (*WebPMultRow)(uint8_t* const ptr, const uint8_t* const alpha, 569 int width, int inverse); 570 571// Same a WebPMultRow(), but for several 'num_rows' rows. 572void WebPMultRows(uint8_t* ptr, int stride, 573 const uint8_t* alpha, int alpha_stride, 574 int width, int num_rows, int inverse); 575 576// Plain-C versions, used as fallback by some implementations. 577void WebPMultRow_C(uint8_t* const ptr, const uint8_t* const alpha, 578 int width, int inverse); 579void WebPMultARGBRow_C(uint32_t* const ptr, int width, int inverse); 580 581// RGB packing function. 'step' can be 3 or 4. r/g/b input is rgb or bgr order. 582extern void (*WebPPackRGB)(const uint8_t* r, const uint8_t* g, const uint8_t* b, 583 int len, int step, uint32_t* out); 584 585// This function returns true if src[i] contains a value different from 0xff. 586extern int (*WebPHasAlpha8b)(const uint8_t* src, int length); 587// This function returns true if src[4*i] contains a value different from 0xff. 588extern int (*WebPHasAlpha32b)(const uint8_t* src, int length); 589 590// To be called first before using the above. 591void WebPInitAlphaProcessing(void); 592 593//------------------------------------------------------------------------------ 594// Filter functions 595 596typedef enum { // Filter types. 597 WEBP_FILTER_NONE = 0, 598 WEBP_FILTER_HORIZONTAL, 599 WEBP_FILTER_VERTICAL, 600 WEBP_FILTER_GRADIENT, 601 WEBP_FILTER_LAST = WEBP_FILTER_GRADIENT + 1, // end marker 602 WEBP_FILTER_BEST, // meta-types 603 WEBP_FILTER_FAST 604} WEBP_FILTER_TYPE; 605 606typedef void (*WebPFilterFunc)(const uint8_t* in, int width, int height, 607 int stride, uint8_t* out); 608// In-place un-filtering. 609// Warning! 'prev_line' pointer can be equal to 'cur_line' or 'preds'. 610typedef void (*WebPUnfilterFunc)(const uint8_t* prev_line, const uint8_t* preds, 611 uint8_t* cur_line, int width); 612 613// Filter the given data using the given predictor. 614// 'in' corresponds to a 2-dimensional pixel array of size (stride * height) 615// in raster order. 616// 'stride' is number of bytes per scan line (with possible padding). 617// 'out' should be pre-allocated. 618extern WebPFilterFunc WebPFilters[WEBP_FILTER_LAST]; 619 620// In-place reconstruct the original data from the given filtered data. 621// The reconstruction will be done for 'num_rows' rows starting from 'row' 622// (assuming rows upto 'row - 1' are already reconstructed). 623extern WebPUnfilterFunc WebPUnfilters[WEBP_FILTER_LAST]; 624 625// To be called first before using the above. 626void VP8FiltersInit(void); 627 628#ifdef __cplusplus 629} // extern "C" 630#endif 631 632#endif /* WEBP_DSP_DSP_H_ */ 633