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 (at) gmail.com) 13 14 #ifndef WEBP_DSP_DSP_H_ 15 #define WEBP_DSP_DSP_H_ 16 17 #ifdef HAVE_CONFIG_H 18 #include "../webp/config.h" 19 #endif 20 21 #include "../webp/types.h" 22 23 #ifdef __cplusplus 24 extern "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 #ifndef __has_builtin 42 # define __has_builtin(x) 0 43 #endif 44 45 #if defined(_MSC_VER) && _MSC_VER > 1310 && \ 46 (defined(_M_X64) || defined(_M_IX86)) 47 #define WEBP_MSC_SSE2 // Visual C++ SSE2 targets 48 #endif 49 50 #if defined(_MSC_VER) && _MSC_VER >= 1500 && \ 51 (defined(_M_X64) || defined(_M_IX86)) 52 #define WEBP_MSC_SSE41 // Visual C++ SSE4.1 targets 53 #endif 54 55 // WEBP_HAVE_* are used to indicate the presence of the instruction set in dsp 56 // files without intrinsics, allowing the corresponding Init() to be called. 57 // Files containing intrinsics will need to be built targeting the instruction 58 // set so should succeed on one of the earlier tests. 59 #if defined(__SSE2__) || defined(WEBP_MSC_SSE2) || defined(WEBP_HAVE_SSE2) 60 #define WEBP_USE_SSE2 61 #endif 62 63 #if defined(__SSE4_1__) || defined(WEBP_MSC_SSE41) || defined(WEBP_HAVE_SSE41) 64 #define WEBP_USE_SSE41 65 #endif 66 67 #if defined(__AVX2__) || defined(WEBP_HAVE_AVX2) 68 #define WEBP_USE_AVX2 69 #endif 70 71 #if defined(__ANDROID__) && defined(__ARM_ARCH_7A__) 72 #define WEBP_ANDROID_NEON // Android targets that might support NEON 73 #endif 74 75 // The intrinsics currently cause compiler errors with arm-nacl-gcc and the 76 // inline assembly would need to be modified for use with Native Client. 77 #if (defined(__ARM_NEON__) || \ 78 defined(__aarch64__) || defined(WEBP_HAVE_NEON)) && \ 79 !defined(__native_client__) 80 #define WEBP_USE_NEON 81 #endif 82 83 #if defined(_MSC_VER) && _MSC_VER >= 1700 && defined(_M_ARM) 84 #define WEBP_USE_NEON 85 #define WEBP_USE_INTRINSICS 86 #endif 87 88 #if defined(__mips__) && !defined(__mips64) && \ 89 defined(__mips_isa_rev) && (__mips_isa_rev >= 1) && (__mips_isa_rev < 6) 90 #define WEBP_USE_MIPS32 91 #if (__mips_isa_rev >= 2) 92 #define WEBP_USE_MIPS32_R2 93 #if defined(__mips_dspr2) || (__mips_dsp_rev >= 2) 94 #define WEBP_USE_MIPS_DSP_R2 95 #endif 96 #endif 97 #endif 98 99 #if defined(__mips_msa) && defined(__mips_isa_rev) && (__mips_isa_rev >= 5) 100 #define WEBP_USE_MSA 101 #endif 102 103 // This macro prevents thread_sanitizer from reporting known concurrent writes. 104 #define WEBP_TSAN_IGNORE_FUNCTION 105 #if defined(__has_feature) 106 #if __has_feature(thread_sanitizer) 107 #undef WEBP_TSAN_IGNORE_FUNCTION 108 #define WEBP_TSAN_IGNORE_FUNCTION __attribute__((no_sanitize_thread)) 109 #endif 110 #endif 111 112 #define WEBP_UBSAN_IGNORE_UNDEF 113 #define WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW 114 #if defined(__clang__) && defined(__has_attribute) 115 #if __has_attribute(no_sanitize) 116 // This macro prevents the undefined behavior sanitizer from reporting 117 // failures. This is only meant to silence unaligned loads on platforms that 118 // are known to support them. 119 #undef WEBP_UBSAN_IGNORE_UNDEF 120 #define WEBP_UBSAN_IGNORE_UNDEF \ 121 __attribute__((no_sanitize("undefined"))) 122 123 // This macro prevents the undefined behavior sanitizer from reporting 124 // failures related to unsigned integer overflows. This is only meant to 125 // silence cases where this well defined behavior is expected. 126 #undef WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW 127 #define WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW \ 128 __attribute__((no_sanitize("unsigned-integer-overflow"))) 129 #endif 130 #endif 131 132 typedef enum { 133 kSSE2, 134 kSSE3, 135 kSlowSSSE3, // special feature for slow SSSE3 architectures 136 kSSE4_1, 137 kAVX, 138 kAVX2, 139 kNEON, 140 kMIPS32, 141 kMIPSdspR2, 142 kMSA 143 } CPUFeature; 144 // returns true if the CPU supports the feature. 145 typedef int (*VP8CPUInfo)(CPUFeature feature); 146 WEBP_EXTERN(VP8CPUInfo) VP8GetCPUInfo; 147 148 //------------------------------------------------------------------------------ 149 // Init stub generator 150 151 // Defines an init function stub to ensure each module exposes a symbol, 152 // avoiding a compiler warning. 153 #define WEBP_DSP_INIT_STUB(func) \ 154 extern void func(void); \ 155 WEBP_TSAN_IGNORE_FUNCTION void func(void) {} 156 157 //------------------------------------------------------------------------------ 158 // Encoding 159 160 // Transforms 161 // VP8Idct: Does one of two inverse transforms. If do_two is set, the transforms 162 // will be done for (ref, in, dst) and (ref + 4, in + 16, dst + 4). 163 typedef void (*VP8Idct)(const uint8_t* ref, const int16_t* in, uint8_t* dst, 164 int do_two); 165 typedef void (*VP8Fdct)(const uint8_t* src, const uint8_t* ref, int16_t* out); 166 typedef void (*VP8WHT)(const int16_t* in, int16_t* out); 167 extern VP8Idct VP8ITransform; 168 extern VP8Fdct VP8FTransform; 169 extern VP8Fdct VP8FTransform2; // performs two transforms at a time 170 extern VP8WHT VP8FTransformWHT; 171 // Predictions 172 // *dst is the destination block. *top and *left can be NULL. 173 typedef void (*VP8IntraPreds)(uint8_t *dst, const uint8_t* left, 174 const uint8_t* top); 175 typedef void (*VP8Intra4Preds)(uint8_t *dst, const uint8_t* top); 176 extern VP8Intra4Preds VP8EncPredLuma4; 177 extern VP8IntraPreds VP8EncPredLuma16; 178 extern VP8IntraPreds VP8EncPredChroma8; 179 180 typedef int (*VP8Metric)(const uint8_t* pix, const uint8_t* ref); 181 extern VP8Metric VP8SSE16x16, VP8SSE16x8, VP8SSE8x8, VP8SSE4x4; 182 typedef int (*VP8WMetric)(const uint8_t* pix, const uint8_t* ref, 183 const uint16_t* const weights); 184 // The weights for VP8TDisto4x4 and VP8TDisto16x16 contain a row-major 185 // 4 by 4 symmetric matrix. 186 extern VP8WMetric VP8TDisto4x4, VP8TDisto16x16; 187 188 // Compute the average (DC) of four 4x4 blocks. 189 // Each sub-4x4 block #i sum is stored in dc[i]. 190 typedef void (*VP8MeanMetric)(const uint8_t* ref, uint32_t dc[4]); 191 extern VP8MeanMetric VP8Mean16x4; 192 193 typedef void (*VP8BlockCopy)(const uint8_t* src, uint8_t* dst); 194 extern VP8BlockCopy VP8Copy4x4; 195 extern VP8BlockCopy VP8Copy16x8; 196 // Quantization 197 struct VP8Matrix; // forward declaration 198 typedef int (*VP8QuantizeBlock)(int16_t in[16], int16_t out[16], 199 const struct VP8Matrix* const mtx); 200 // Same as VP8QuantizeBlock, but quantizes two consecutive blocks. 201 typedef int (*VP8Quantize2Blocks)(int16_t in[32], int16_t out[32], 202 const struct VP8Matrix* const mtx); 203 204 extern VP8QuantizeBlock VP8EncQuantizeBlock; 205 extern VP8Quantize2Blocks VP8EncQuantize2Blocks; 206 207 // specific to 2nd transform: 208 typedef int (*VP8QuantizeBlockWHT)(int16_t in[16], int16_t out[16], 209 const struct VP8Matrix* const mtx); 210 extern VP8QuantizeBlockWHT VP8EncQuantizeBlockWHT; 211 212 extern const int VP8DspScan[16 + 4 + 4]; 213 214 // Collect histogram for susceptibility calculation. 215 #define MAX_COEFF_THRESH 31 // size of histogram used by CollectHistogram. 216 typedef struct { 217 // We only need to store max_value and last_non_zero, not the distribution. 218 int max_value; 219 int last_non_zero; 220 } VP8Histogram; 221 typedef void (*VP8CHisto)(const uint8_t* ref, const uint8_t* pred, 222 int start_block, int end_block, 223 VP8Histogram* const histo); 224 extern VP8CHisto VP8CollectHistogram; 225 // General-purpose util function to help VP8CollectHistogram(). 226 void VP8SetHistogramData(const int distribution[MAX_COEFF_THRESH + 1], 227 VP8Histogram* const histo); 228 229 // must be called before using any of the above 230 void VP8EncDspInit(void); 231 232 //------------------------------------------------------------------------------ 233 // cost functions (encoding) 234 235 extern const uint16_t VP8EntropyCost[256]; // 8bit fixed-point log(p) 236 // approximate cost per level: 237 extern const uint16_t VP8LevelFixedCosts[2047 /*MAX_LEVEL*/ + 1]; 238 extern const uint8_t VP8EncBands[16 + 1]; 239 240 struct VP8Residual; 241 typedef void (*VP8SetResidualCoeffsFunc)(const int16_t* const coeffs, 242 struct VP8Residual* const res); 243 extern VP8SetResidualCoeffsFunc VP8SetResidualCoeffs; 244 245 // Cost calculation function. 246 typedef int (*VP8GetResidualCostFunc)(int ctx0, 247 const struct VP8Residual* const res); 248 extern VP8GetResidualCostFunc VP8GetResidualCost; 249 250 // must be called before anything using the above 251 void VP8EncDspCostInit(void); 252 253 //------------------------------------------------------------------------------ 254 // SSIM / PSNR utils 255 256 // struct for accumulating statistical moments 257 typedef struct { 258 uint32_t w; // sum(w_i) : sum of weights 259 uint32_t xm, ym; // sum(w_i * x_i), sum(w_i * y_i) 260 uint32_t xxm, xym, yym; // sum(w_i * x_i * x_i), etc. 261 } VP8DistoStats; 262 263 // Compute the final SSIM value 264 // The non-clipped version assumes stats->w = (2 * VP8_SSIM_KERNEL + 1)^2. 265 double VP8SSIMFromStats(const VP8DistoStats* const stats); 266 double VP8SSIMFromStatsClipped(const VP8DistoStats* const stats); 267 268 #define VP8_SSIM_KERNEL 3 // total size of the kernel: 2 * VP8_SSIM_KERNEL + 1 269 typedef double (*VP8SSIMGetClippedFunc)(const uint8_t* src1, int stride1, 270 const uint8_t* src2, int stride2, 271 int xo, int yo, // center position 272 int W, int H); // plane dimension 273 274 // This version is called with the guarantee that you can load 8 bytes and 275 // 8 rows at offset src1 and src2 276 typedef double (*VP8SSIMGetFunc)(const uint8_t* src1, int stride1, 277 const uint8_t* src2, int stride2); 278 279 extern VP8SSIMGetFunc VP8SSIMGet; // unclipped / unchecked 280 extern VP8SSIMGetClippedFunc VP8SSIMGetClipped; // with clipping 281 282 typedef uint32_t (*VP8AccumulateSSEFunc)(const uint8_t* src1, 283 const uint8_t* src2, int len); 284 extern VP8AccumulateSSEFunc VP8AccumulateSSE; 285 286 // must be called before using any of the above directly 287 void VP8SSIMDspInit(void); 288 289 //------------------------------------------------------------------------------ 290 // Decoding 291 292 typedef void (*VP8DecIdct)(const int16_t* coeffs, uint8_t* dst); 293 // when doing two transforms, coeffs is actually int16_t[2][16]. 294 typedef void (*VP8DecIdct2)(const int16_t* coeffs, uint8_t* dst, int do_two); 295 extern VP8DecIdct2 VP8Transform; 296 extern VP8DecIdct VP8TransformAC3; 297 extern VP8DecIdct VP8TransformUV; 298 extern VP8DecIdct VP8TransformDC; 299 extern VP8DecIdct VP8TransformDCUV; 300 extern VP8WHT VP8TransformWHT; 301 302 // *dst is the destination block, with stride BPS. Boundary samples are 303 // assumed accessible when needed. 304 typedef void (*VP8PredFunc)(uint8_t* dst); 305 extern VP8PredFunc VP8PredLuma16[/* NUM_B_DC_MODES */]; 306 extern VP8PredFunc VP8PredChroma8[/* NUM_B_DC_MODES */]; 307 extern VP8PredFunc VP8PredLuma4[/* NUM_BMODES */]; 308 309 // clipping tables (for filtering) 310 extern const int8_t* const VP8ksclip1; // clips [-1020, 1020] to [-128, 127] 311 extern const int8_t* const VP8ksclip2; // clips [-112, 112] to [-16, 15] 312 extern const uint8_t* const VP8kclip1; // clips [-255,511] to [0,255] 313 extern const uint8_t* const VP8kabs0; // abs(x) for x in [-255,255] 314 // must be called first 315 void VP8InitClipTables(void); 316 317 // simple filter (only for luma) 318 typedef void (*VP8SimpleFilterFunc)(uint8_t* p, int stride, int thresh); 319 extern VP8SimpleFilterFunc VP8SimpleVFilter16; 320 extern VP8SimpleFilterFunc VP8SimpleHFilter16; 321 extern VP8SimpleFilterFunc VP8SimpleVFilter16i; // filter 3 inner edges 322 extern VP8SimpleFilterFunc VP8SimpleHFilter16i; 323 324 // regular filter (on both macroblock edges and inner edges) 325 typedef void (*VP8LumaFilterFunc)(uint8_t* luma, int stride, 326 int thresh, int ithresh, int hev_t); 327 typedef void (*VP8ChromaFilterFunc)(uint8_t* u, uint8_t* v, int stride, 328 int thresh, int ithresh, int hev_t); 329 // on outer edge 330 extern VP8LumaFilterFunc VP8VFilter16; 331 extern VP8LumaFilterFunc VP8HFilter16; 332 extern VP8ChromaFilterFunc VP8VFilter8; 333 extern VP8ChromaFilterFunc VP8HFilter8; 334 335 // on inner edge 336 extern VP8LumaFilterFunc VP8VFilter16i; // filtering 3 inner edges altogether 337 extern VP8LumaFilterFunc VP8HFilter16i; 338 extern VP8ChromaFilterFunc VP8VFilter8i; // filtering u and v altogether 339 extern VP8ChromaFilterFunc VP8HFilter8i; 340 341 // Dithering. Combines dithering values (centered around 128) with dst[], 342 // according to: dst[] = clip(dst[] + (((dither[]-128) + 8) >> 4) 343 #define VP8_DITHER_DESCALE 4 344 #define VP8_DITHER_DESCALE_ROUNDER (1 << (VP8_DITHER_DESCALE - 1)) 345 #define VP8_DITHER_AMP_BITS 7 346 #define VP8_DITHER_AMP_CENTER (1 << VP8_DITHER_AMP_BITS) 347 extern void (*VP8DitherCombine8x8)(const uint8_t* dither, uint8_t* dst, 348 int dst_stride); 349 350 // must be called before anything using the above 351 void VP8DspInit(void); 352 353 //------------------------------------------------------------------------------ 354 // WebP I/O 355 356 #define FANCY_UPSAMPLING // undefined to remove fancy upsampling support 357 358 // Convert a pair of y/u/v lines together to the output rgb/a colorspace. 359 // bottom_y can be NULL if only one line of output is needed (at top/bottom). 360 typedef void (*WebPUpsampleLinePairFunc)( 361 const uint8_t* top_y, const uint8_t* bottom_y, 362 const uint8_t* top_u, const uint8_t* top_v, 363 const uint8_t* cur_u, const uint8_t* cur_v, 364 uint8_t* top_dst, uint8_t* bottom_dst, int len); 365 366 #ifdef FANCY_UPSAMPLING 367 368 // Fancy upsampling functions to convert YUV to RGB(A) modes 369 extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */]; 370 371 #endif // FANCY_UPSAMPLING 372 373 // Per-row point-sampling methods. 374 typedef void (*WebPSamplerRowFunc)(const uint8_t* y, 375 const uint8_t* u, const uint8_t* v, 376 uint8_t* dst, int len); 377 // Generic function to apply 'WebPSamplerRowFunc' to the whole plane: 378 void WebPSamplerProcessPlane(const uint8_t* y, int y_stride, 379 const uint8_t* u, const uint8_t* v, int uv_stride, 380 uint8_t* dst, int dst_stride, 381 int width, int height, WebPSamplerRowFunc func); 382 383 // Sampling functions to convert rows of YUV to RGB(A) 384 extern WebPSamplerRowFunc WebPSamplers[/* MODE_LAST */]; 385 386 // General function for converting two lines of ARGB or RGBA. 387 // 'alpha_is_last' should be true if 0xff000000 is stored in memory as 388 // as 0x00, 0x00, 0x00, 0xff (little endian). 389 WebPUpsampleLinePairFunc WebPGetLinePairConverter(int alpha_is_last); 390 391 // YUV444->RGB converters 392 typedef void (*WebPYUV444Converter)(const uint8_t* y, 393 const uint8_t* u, const uint8_t* v, 394 uint8_t* dst, int len); 395 396 extern WebPYUV444Converter WebPYUV444Converters[/* MODE_LAST */]; 397 398 // Must be called before using the WebPUpsamplers[] (and for premultiplied 399 // colorspaces like rgbA, rgbA4444, etc) 400 void WebPInitUpsamplers(void); 401 // Must be called before using WebPSamplers[] 402 void WebPInitSamplers(void); 403 // Must be called before using WebPYUV444Converters[] 404 void WebPInitYUV444Converters(void); 405 406 //------------------------------------------------------------------------------ 407 // ARGB -> YUV converters 408 409 // Convert ARGB samples to luma Y. 410 extern void (*WebPConvertARGBToY)(const uint32_t* argb, uint8_t* y, int width); 411 // Convert ARGB samples to U/V with downsampling. do_store should be '1' for 412 // even lines and '0' for odd ones. 'src_width' is the original width, not 413 // the U/V one. 414 extern void (*WebPConvertARGBToUV)(const uint32_t* argb, uint8_t* u, uint8_t* v, 415 int src_width, int do_store); 416 417 // Convert a row of accumulated (four-values) of rgba32 toward U/V 418 extern void (*WebPConvertRGBA32ToUV)(const uint16_t* rgb, 419 uint8_t* u, uint8_t* v, int width); 420 421 // Convert RGB or BGR to Y 422 extern void (*WebPConvertRGB24ToY)(const uint8_t* rgb, uint8_t* y, int width); 423 extern void (*WebPConvertBGR24ToY)(const uint8_t* bgr, uint8_t* y, int width); 424 425 // used for plain-C fallback. 426 extern void WebPConvertARGBToUV_C(const uint32_t* argb, uint8_t* u, uint8_t* v, 427 int src_width, int do_store); 428 extern void WebPConvertRGBA32ToUV_C(const uint16_t* rgb, 429 uint8_t* u, uint8_t* v, int width); 430 431 // utilities for accurate RGB->YUV conversion 432 extern uint64_t (*WebPSharpYUVUpdateY)(const uint16_t* src, const uint16_t* ref, 433 uint16_t* dst, int len); 434 extern void (*WebPSharpYUVUpdateRGB)(const int16_t* src, const int16_t* ref, 435 int16_t* dst, int len); 436 extern void (*WebPSharpYUVFilterRow)(const int16_t* A, const int16_t* B, 437 int len, 438 const uint16_t* best_y, uint16_t* out); 439 440 // Must be called before using the above. 441 void WebPInitConvertARGBToYUV(void); 442 443 //------------------------------------------------------------------------------ 444 // Rescaler 445 446 struct WebPRescaler; 447 448 // Import a row of data and save its contribution in the rescaler. 449 // 'channel' denotes the channel number to be imported. 'Expand' corresponds to 450 // the wrk->x_expand case. Otherwise, 'Shrink' is to be used. 451 typedef void (*WebPRescalerImportRowFunc)(struct WebPRescaler* const wrk, 452 const uint8_t* src); 453 454 extern WebPRescalerImportRowFunc WebPRescalerImportRowExpand; 455 extern WebPRescalerImportRowFunc WebPRescalerImportRowShrink; 456 457 // Export one row (starting at x_out position) from rescaler. 458 // 'Expand' corresponds to the wrk->y_expand case. 459 // Otherwise 'Shrink' is to be used 460 typedef void (*WebPRescalerExportRowFunc)(struct WebPRescaler* const wrk); 461 extern WebPRescalerExportRowFunc WebPRescalerExportRowExpand; 462 extern WebPRescalerExportRowFunc WebPRescalerExportRowShrink; 463 464 // Plain-C implementation, as fall-back. 465 extern void WebPRescalerImportRowExpandC(struct WebPRescaler* const wrk, 466 const uint8_t* src); 467 extern void WebPRescalerImportRowShrinkC(struct WebPRescaler* const wrk, 468 const uint8_t* src); 469 extern void WebPRescalerExportRowExpandC(struct WebPRescaler* const wrk); 470 extern void WebPRescalerExportRowShrinkC(struct WebPRescaler* const wrk); 471 472 // Main entry calls: 473 extern void WebPRescalerImportRow(struct WebPRescaler* const wrk, 474 const uint8_t* src); 475 // Export one row (starting at x_out position) from rescaler. 476 extern void WebPRescalerExportRow(struct WebPRescaler* const wrk); 477 478 // Must be called first before using the above. 479 void WebPRescalerDspInit(void); 480 481 //------------------------------------------------------------------------------ 482 // Utilities for processing transparent channel. 483 484 // Apply alpha pre-multiply on an rgba, bgra or argb plane of size w * h. 485 // alpha_first should be 0 for argb, 1 for rgba or bgra (where alpha is last). 486 extern void (*WebPApplyAlphaMultiply)( 487 uint8_t* rgba, int alpha_first, int w, int h, int stride); 488 489 // Same, buf specifically for RGBA4444 format 490 extern void (*WebPApplyAlphaMultiply4444)( 491 uint8_t* rgba4444, int w, int h, int stride); 492 493 // Dispatch the values from alpha[] plane to the ARGB destination 'dst'. 494 // Returns true if alpha[] plane has non-trivial values different from 0xff. 495 extern int (*WebPDispatchAlpha)(const uint8_t* alpha, int alpha_stride, 496 int width, int height, 497 uint8_t* dst, int dst_stride); 498 499 // Transfer packed 8b alpha[] values to green channel in dst[], zero'ing the 500 // A/R/B values. 'dst_stride' is the stride for dst[] in uint32_t units. 501 extern void (*WebPDispatchAlphaToGreen)(const uint8_t* alpha, int alpha_stride, 502 int width, int height, 503 uint32_t* dst, int dst_stride); 504 505 // Extract the alpha values from 32b values in argb[] and pack them into alpha[] 506 // (this is the opposite of WebPDispatchAlpha). 507 // Returns true if there's only trivial 0xff alpha values. 508 extern int (*WebPExtractAlpha)(const uint8_t* argb, int argb_stride, 509 int width, int height, 510 uint8_t* alpha, int alpha_stride); 511 512 // Extract the green values from 32b values in argb[] and pack them into alpha[] 513 // (this is the opposite of WebPDispatchAlphaToGreen). 514 extern void (*WebPExtractGreen)(const uint32_t* argb, uint8_t* alpha, int size); 515 516 // Pre-Multiply operation transforms x into x * A / 255 (where x=Y,R,G or B). 517 // Un-Multiply operation transforms x into x * 255 / A. 518 519 // Pre-Multiply or Un-Multiply (if 'inverse' is true) argb values in a row. 520 extern void (*WebPMultARGBRow)(uint32_t* const ptr, int width, int inverse); 521 522 // Same a WebPMultARGBRow(), but for several rows. 523 void WebPMultARGBRows(uint8_t* ptr, int stride, int width, int num_rows, 524 int inverse); 525 526 // Same for a row of single values, with side alpha values. 527 extern void (*WebPMultRow)(uint8_t* const ptr, const uint8_t* const alpha, 528 int width, int inverse); 529 530 // Same a WebPMultRow(), but for several 'num_rows' rows. 531 void WebPMultRows(uint8_t* ptr, int stride, 532 const uint8_t* alpha, int alpha_stride, 533 int width, int num_rows, int inverse); 534 535 // Plain-C versions, used as fallback by some implementations. 536 void WebPMultRowC(uint8_t* const ptr, const uint8_t* const alpha, 537 int width, int inverse); 538 void WebPMultARGBRowC(uint32_t* const ptr, int width, int inverse); 539 540 // To be called first before using the above. 541 void WebPInitAlphaProcessing(void); 542 543 // ARGB packing function: a/r/g/b input is rgba or bgra order. 544 extern void (*VP8PackARGB)(const uint8_t* a, const uint8_t* r, 545 const uint8_t* g, const uint8_t* b, int len, 546 uint32_t* out); 547 548 // RGB packing function. 'step' can be 3 or 4. r/g/b input is rgb or bgr order. 549 extern void (*VP8PackRGB)(const uint8_t* r, const uint8_t* g, const uint8_t* b, 550 int len, int step, uint32_t* out); 551 552 // To be called first before using the above. 553 void VP8EncDspARGBInit(void); 554 555 //------------------------------------------------------------------------------ 556 // Filter functions 557 558 typedef enum { // Filter types. 559 WEBP_FILTER_NONE = 0, 560 WEBP_FILTER_HORIZONTAL, 561 WEBP_FILTER_VERTICAL, 562 WEBP_FILTER_GRADIENT, 563 WEBP_FILTER_LAST = WEBP_FILTER_GRADIENT + 1, // end marker 564 WEBP_FILTER_BEST, // meta-types 565 WEBP_FILTER_FAST 566 } WEBP_FILTER_TYPE; 567 568 typedef void (*WebPFilterFunc)(const uint8_t* in, int width, int height, 569 int stride, uint8_t* out); 570 // In-place un-filtering. 571 // Warning! 'prev_line' pointer can be equal to 'cur_line' or 'preds'. 572 typedef void (*WebPUnfilterFunc)(const uint8_t* prev_line, const uint8_t* preds, 573 uint8_t* cur_line, int width); 574 575 // Filter the given data using the given predictor. 576 // 'in' corresponds to a 2-dimensional pixel array of size (stride * height) 577 // in raster order. 578 // 'stride' is number of bytes per scan line (with possible padding). 579 // 'out' should be pre-allocated. 580 extern WebPFilterFunc WebPFilters[WEBP_FILTER_LAST]; 581 582 // In-place reconstruct the original data from the given filtered data. 583 // The reconstruction will be done for 'num_rows' rows starting from 'row' 584 // (assuming rows upto 'row - 1' are already reconstructed). 585 extern WebPUnfilterFunc WebPUnfilters[WEBP_FILTER_LAST]; 586 587 // To be called first before using the above. 588 void VP8FiltersInit(void); 589 590 #ifdef __cplusplus 591 } // extern "C" 592 #endif 593 594 #endif /* WEBP_DSP_DSP_H_ */ 595
