dsp.h (23712B)
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/dsp/cpu.h" 22 #include "src/webp/types.h" 23 24 #ifdef __cplusplus 25 extern "C" { 26 #endif 27 28 #define BPS 32 // this is the common stride for enc/dec 29 30 //------------------------------------------------------------------------------ 31 // WEBP_RESTRICT 32 33 // Declares a pointer with the restrict type qualifier if available. 34 // This allows code to hint to the compiler that only this pointer references a 35 // particular object or memory region within the scope of the block in which it 36 // is declared. This may allow for improved optimizations due to the lack of 37 // pointer aliasing. See also: 38 // https://en.cppreference.com/w/c/language/restrict 39 #if defined(__GNUC__) 40 #define WEBP_RESTRICT __restrict__ 41 #elif defined(_MSC_VER) 42 #define WEBP_RESTRICT __restrict 43 #else 44 #define WEBP_RESTRICT 45 #endif 46 47 48 //------------------------------------------------------------------------------ 49 // Init stub generator 50 51 // Defines an init function stub to ensure each module exposes a symbol, 52 // avoiding a compiler warning. 53 #define WEBP_DSP_INIT_STUB(func) \ 54 extern void func(void); \ 55 void func(void) {} 56 57 //------------------------------------------------------------------------------ 58 // Encoding 59 60 // Transforms 61 // VP8Idct: Does one of two inverse transforms. If do_two is set, the transforms 62 // will be done for (ref, in, dst) and (ref + 4, in + 16, dst + 4). 63 typedef void (*VP8Idct)(const uint8_t* WEBP_RESTRICT ref, 64 const int16_t* WEBP_RESTRICT in, 65 uint8_t* WEBP_RESTRICT dst, int do_two); 66 typedef void (*VP8Fdct)(const uint8_t* WEBP_RESTRICT src, 67 const uint8_t* WEBP_RESTRICT ref, 68 int16_t* WEBP_RESTRICT out); 69 typedef void (*VP8WHT)(const int16_t* WEBP_RESTRICT in, 70 int16_t* WEBP_RESTRICT out); 71 extern VP8Idct VP8ITransform; 72 extern VP8Fdct VP8FTransform; 73 extern VP8Fdct VP8FTransform2; // performs two transforms at a time 74 extern VP8WHT VP8FTransformWHT; 75 // Predictions 76 // *dst is the destination block. *top and *left can be NULL. 77 typedef void (*VP8IntraPreds)(uint8_t* WEBP_RESTRICT dst, 78 const uint8_t* WEBP_RESTRICT left, 79 const uint8_t* WEBP_RESTRICT top); 80 typedef void (*VP8Intra4Preds)(uint8_t* WEBP_RESTRICT dst, 81 const uint8_t* WEBP_RESTRICT top); 82 extern VP8Intra4Preds VP8EncPredLuma4; 83 extern VP8IntraPreds VP8EncPredLuma16; 84 extern VP8IntraPreds VP8EncPredChroma8; 85 86 typedef int (*VP8Metric)(const uint8_t* WEBP_RESTRICT pix, 87 const uint8_t* WEBP_RESTRICT ref); 88 extern VP8Metric VP8SSE16x16, VP8SSE16x8, VP8SSE8x8, VP8SSE4x4; 89 typedef int (*VP8WMetric)(const uint8_t* WEBP_RESTRICT pix, 90 const uint8_t* WEBP_RESTRICT ref, 91 const uint16_t* WEBP_RESTRICT const weights); 92 // The weights for VP8TDisto4x4 and VP8TDisto16x16 contain a row-major 93 // 4 by 4 symmetric matrix. 94 extern VP8WMetric VP8TDisto4x4, VP8TDisto16x16; 95 96 // Compute the average (DC) of four 4x4 blocks. 97 // Each sub-4x4 block #i sum is stored in dc[i]. 98 typedef void (*VP8MeanMetric)(const uint8_t* WEBP_RESTRICT ref, 99 uint32_t dc[4]); 100 extern VP8MeanMetric VP8Mean16x4; 101 102 typedef void (*VP8BlockCopy)(const uint8_t* WEBP_RESTRICT src, 103 uint8_t* WEBP_RESTRICT dst); 104 extern VP8BlockCopy VP8Copy4x4; 105 extern VP8BlockCopy VP8Copy16x8; 106 // Quantization 107 struct VP8Matrix; // forward declaration 108 typedef int (*VP8QuantizeBlock)( 109 int16_t in[16], int16_t out[16], 110 const struct VP8Matrix* WEBP_RESTRICT const mtx); 111 // Same as VP8QuantizeBlock, but quantizes two consecutive blocks. 112 typedef int (*VP8Quantize2Blocks)( 113 int16_t in[32], int16_t out[32], 114 const struct VP8Matrix* WEBP_RESTRICT const mtx); 115 116 extern VP8QuantizeBlock VP8EncQuantizeBlock; 117 extern VP8Quantize2Blocks VP8EncQuantize2Blocks; 118 119 // specific to 2nd transform: 120 typedef int (*VP8QuantizeBlockWHT)( 121 int16_t in[16], int16_t out[16], 122 const struct VP8Matrix* WEBP_RESTRICT const mtx); 123 extern VP8QuantizeBlockWHT VP8EncQuantizeBlockWHT; 124 125 extern const int VP8DspScan[16 + 4 + 4]; 126 127 // Collect histogram for susceptibility calculation. 128 #define MAX_COEFF_THRESH 31 // size of histogram used by CollectHistogram. 129 typedef struct { 130 // We only need to store max_value and last_non_zero, not the distribution. 131 int max_value; 132 int last_non_zero; 133 } VP8Histogram; 134 typedef void (*VP8CHisto)(const uint8_t* WEBP_RESTRICT ref, 135 const uint8_t* WEBP_RESTRICT pred, 136 int start_block, int end_block, 137 VP8Histogram* WEBP_RESTRICT const histo); 138 extern VP8CHisto VP8CollectHistogram; 139 // General-purpose util function to help VP8CollectHistogram(). 140 void VP8SetHistogramData(const int distribution[MAX_COEFF_THRESH + 1], 141 VP8Histogram* const histo); 142 143 // must be called before using any of the above 144 void VP8EncDspInit(void); 145 146 //------------------------------------------------------------------------------ 147 // cost functions (encoding) 148 149 extern const uint16_t VP8EntropyCost[256]; // 8bit fixed-point log(p) 150 // approximate cost per level: 151 extern const uint16_t VP8LevelFixedCosts[2047 /*MAX_LEVEL*/ + 1]; 152 extern const uint8_t VP8EncBands[16 + 1]; 153 154 struct VP8Residual; 155 typedef void (*VP8SetResidualCoeffsFunc)( 156 const int16_t* WEBP_RESTRICT const coeffs, 157 struct VP8Residual* WEBP_RESTRICT const res); 158 extern VP8SetResidualCoeffsFunc VP8SetResidualCoeffs; 159 160 // Cost calculation function. 161 typedef int (*VP8GetResidualCostFunc)(int ctx0, 162 const struct VP8Residual* const res); 163 extern VP8GetResidualCostFunc VP8GetResidualCost; 164 165 // must be called before anything using the above 166 void VP8EncDspCostInit(void); 167 168 //------------------------------------------------------------------------------ 169 // SSIM / PSNR utils 170 171 // struct for accumulating statistical moments 172 typedef struct { 173 uint32_t w; // sum(w_i) : sum of weights 174 uint32_t xm, ym; // sum(w_i * x_i), sum(w_i * y_i) 175 uint32_t xxm, xym, yym; // sum(w_i * x_i * x_i), etc. 176 } VP8DistoStats; 177 178 // Compute the final SSIM value 179 // The non-clipped version assumes stats->w = (2 * VP8_SSIM_KERNEL + 1)^2. 180 double VP8SSIMFromStats(const VP8DistoStats* const stats); 181 double VP8SSIMFromStatsClipped(const VP8DistoStats* const stats); 182 183 #define VP8_SSIM_KERNEL 3 // total size of the kernel: 2 * VP8_SSIM_KERNEL + 1 184 typedef double (*VP8SSIMGetClippedFunc)(const uint8_t* src1, int stride1, 185 const uint8_t* src2, int stride2, 186 int xo, int yo, // center position 187 int W, int H); // plane dimension 188 189 #if !defined(WEBP_REDUCE_SIZE) 190 // This version is called with the guarantee that you can load 8 bytes and 191 // 8 rows at offset src1 and src2 192 typedef double (*VP8SSIMGetFunc)(const uint8_t* src1, int stride1, 193 const uint8_t* src2, int stride2); 194 195 extern VP8SSIMGetFunc VP8SSIMGet; // unclipped / unchecked 196 extern VP8SSIMGetClippedFunc VP8SSIMGetClipped; // with clipping 197 #endif 198 199 #if !defined(WEBP_DISABLE_STATS) 200 typedef uint32_t (*VP8AccumulateSSEFunc)(const uint8_t* src1, 201 const uint8_t* src2, int len); 202 extern VP8AccumulateSSEFunc VP8AccumulateSSE; 203 #endif 204 205 // must be called before using any of the above directly 206 void VP8SSIMDspInit(void); 207 208 //------------------------------------------------------------------------------ 209 // Decoding 210 211 typedef void (*VP8DecIdct)(const int16_t* WEBP_RESTRICT coeffs, 212 uint8_t* WEBP_RESTRICT dst); 213 // when doing two transforms, coeffs is actually int16_t[2][16]. 214 typedef void (*VP8DecIdct2)(const int16_t* WEBP_RESTRICT coeffs, 215 uint8_t* WEBP_RESTRICT dst, int do_two); 216 extern VP8DecIdct2 VP8Transform; 217 extern VP8DecIdct VP8TransformAC3; 218 extern VP8DecIdct VP8TransformUV; 219 extern VP8DecIdct VP8TransformDC; 220 extern VP8DecIdct VP8TransformDCUV; 221 extern VP8WHT VP8TransformWHT; 222 223 #define WEBP_TRANSFORM_AC3_C1 20091 224 #define WEBP_TRANSFORM_AC3_C2 35468 225 #define WEBP_TRANSFORM_AC3_MUL1(a) ((((a) * WEBP_TRANSFORM_AC3_C1) >> 16) + (a)) 226 #define WEBP_TRANSFORM_AC3_MUL2(a) (((a) * WEBP_TRANSFORM_AC3_C2) >> 16) 227 228 // *dst is the destination block, with stride BPS. Boundary samples are 229 // assumed accessible when needed. 230 typedef void (*VP8PredFunc)(uint8_t* dst); 231 extern VP8PredFunc VP8PredLuma16[/* NUM_B_DC_MODES */]; 232 extern VP8PredFunc VP8PredChroma8[/* NUM_B_DC_MODES */]; 233 extern VP8PredFunc VP8PredLuma4[/* NUM_BMODES */]; 234 235 // clipping tables (for filtering) 236 extern const int8_t* const VP8ksclip1; // clips [-1020, 1020] to [-128, 127] 237 extern const int8_t* const VP8ksclip2; // clips [-112, 112] to [-16, 15] 238 extern const uint8_t* const VP8kclip1; // clips [-255,511] to [0,255] 239 extern const uint8_t* const VP8kabs0; // abs(x) for x in [-255,255] 240 // must be called first 241 void VP8InitClipTables(void); 242 243 // simple filter (only for luma) 244 typedef void (*VP8SimpleFilterFunc)(uint8_t* p, int stride, int thresh); 245 extern VP8SimpleFilterFunc VP8SimpleVFilter16; 246 extern VP8SimpleFilterFunc VP8SimpleHFilter16; 247 extern VP8SimpleFilterFunc VP8SimpleVFilter16i; // filter 3 inner edges 248 extern VP8SimpleFilterFunc VP8SimpleHFilter16i; 249 250 // regular filter (on both macroblock edges and inner edges) 251 typedef void (*VP8LumaFilterFunc)(uint8_t* luma, int stride, 252 int thresh, int ithresh, int hev_t); 253 typedef void (*VP8ChromaFilterFunc)(uint8_t* WEBP_RESTRICT u, 254 uint8_t* WEBP_RESTRICT v, int stride, 255 int thresh, int ithresh, int hev_t); 256 // on outer edge 257 extern VP8LumaFilterFunc VP8VFilter16; 258 extern VP8LumaFilterFunc VP8HFilter16; 259 extern VP8ChromaFilterFunc VP8VFilter8; 260 extern VP8ChromaFilterFunc VP8HFilter8; 261 262 // on inner edge 263 extern VP8LumaFilterFunc VP8VFilter16i; // filtering 3 inner edges altogether 264 extern VP8LumaFilterFunc VP8HFilter16i; 265 extern VP8ChromaFilterFunc VP8VFilter8i; // filtering u and v altogether 266 extern VP8ChromaFilterFunc VP8HFilter8i; 267 268 // Dithering. Combines dithering values (centered around 128) with dst[], 269 // according to: dst[] = clip(dst[] + (((dither[]-128) + 8) >> 4) 270 #define VP8_DITHER_DESCALE 4 271 #define VP8_DITHER_DESCALE_ROUNDER (1 << (VP8_DITHER_DESCALE - 1)) 272 #define VP8_DITHER_AMP_BITS 7 273 #define VP8_DITHER_AMP_CENTER (1 << VP8_DITHER_AMP_BITS) 274 extern void (*VP8DitherCombine8x8)(const uint8_t* WEBP_RESTRICT dither, 275 uint8_t* WEBP_RESTRICT dst, int dst_stride); 276 277 // must be called before anything using the above 278 void VP8DspInit(void); 279 280 //------------------------------------------------------------------------------ 281 // WebP I/O 282 283 #define FANCY_UPSAMPLING // undefined to remove fancy upsampling support 284 285 // Convert a pair of y/u/v lines together to the output rgb/a colorspace. 286 // bottom_y can be NULL if only one line of output is needed (at top/bottom). 287 typedef void (*WebPUpsampleLinePairFunc)( 288 const uint8_t* WEBP_RESTRICT top_y, const uint8_t* WEBP_RESTRICT bottom_y, 289 const uint8_t* WEBP_RESTRICT top_u, const uint8_t* WEBP_RESTRICT top_v, 290 const uint8_t* WEBP_RESTRICT cur_u, const uint8_t* WEBP_RESTRICT cur_v, 291 uint8_t* WEBP_RESTRICT top_dst, uint8_t* WEBP_RESTRICT bottom_dst, int len); 292 293 #ifdef FANCY_UPSAMPLING 294 295 // Fancy upsampling functions to convert YUV to RGB(A) modes 296 extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */]; 297 298 #endif // FANCY_UPSAMPLING 299 300 // Per-row point-sampling methods. 301 typedef void (*WebPSamplerRowFunc)(const uint8_t* WEBP_RESTRICT y, 302 const uint8_t* WEBP_RESTRICT u, 303 const uint8_t* WEBP_RESTRICT v, 304 uint8_t* WEBP_RESTRICT dst, int len); 305 // Generic function to apply 'WebPSamplerRowFunc' to the whole plane: 306 void WebPSamplerProcessPlane(const uint8_t* WEBP_RESTRICT y, int y_stride, 307 const uint8_t* WEBP_RESTRICT u, 308 const uint8_t* WEBP_RESTRICT v, int uv_stride, 309 uint8_t* WEBP_RESTRICT dst, int dst_stride, 310 int width, int height, WebPSamplerRowFunc func); 311 312 // Sampling functions to convert rows of YUV to RGB(A) 313 extern WebPSamplerRowFunc WebPSamplers[/* MODE_LAST */]; 314 315 // General function for converting two lines of ARGB or RGBA. 316 // 'alpha_is_last' should be true if 0xff000000 is stored in memory as 317 // as 0x00, 0x00, 0x00, 0xff (little endian). 318 WebPUpsampleLinePairFunc WebPGetLinePairConverter(int alpha_is_last); 319 320 // YUV444->RGB converters 321 typedef void (*WebPYUV444Converter)(const uint8_t* WEBP_RESTRICT y, 322 const uint8_t* WEBP_RESTRICT u, 323 const uint8_t* WEBP_RESTRICT v, 324 uint8_t* WEBP_RESTRICT dst, int len); 325 326 extern WebPYUV444Converter WebPYUV444Converters[/* MODE_LAST */]; 327 328 // Must be called before using the WebPUpsamplers[] (and for premultiplied 329 // colorspaces like rgbA, rgbA4444, etc) 330 void WebPInitUpsamplers(void); 331 // Must be called before using WebPSamplers[] 332 void WebPInitSamplers(void); 333 // Must be called before using WebPYUV444Converters[] 334 void WebPInitYUV444Converters(void); 335 336 //------------------------------------------------------------------------------ 337 // ARGB -> YUV converters 338 339 // Convert ARGB samples to luma Y. 340 extern void (*WebPConvertARGBToY)(const uint32_t* WEBP_RESTRICT argb, 341 uint8_t* WEBP_RESTRICT y, int width); 342 // Convert ARGB samples to U/V with downsampling. do_store should be '1' for 343 // even lines and '0' for odd ones. 'src_width' is the original width, not 344 // the U/V one. 345 extern void (*WebPConvertARGBToUV)(const uint32_t* WEBP_RESTRICT argb, 346 uint8_t* WEBP_RESTRICT u, 347 uint8_t* WEBP_RESTRICT v, 348 int src_width, int do_store); 349 350 // Convert a row of accumulated (four-values) of rgba32 toward U/V 351 extern void (*WebPConvertRGBA32ToUV)(const uint16_t* WEBP_RESTRICT rgb, 352 uint8_t* WEBP_RESTRICT u, 353 uint8_t* WEBP_RESTRICT v, int width); 354 355 // Convert RGB or BGR to Y 356 extern void (*WebPConvertRGB24ToY)(const uint8_t* WEBP_RESTRICT rgb, 357 uint8_t* WEBP_RESTRICT y, int width); 358 extern void (*WebPConvertBGR24ToY)(const uint8_t* WEBP_RESTRICT bgr, 359 uint8_t* WEBP_RESTRICT y, int width); 360 361 // used for plain-C fallback. 362 extern void WebPConvertARGBToUV_C(const uint32_t* WEBP_RESTRICT argb, 363 uint8_t* WEBP_RESTRICT u, 364 uint8_t* WEBP_RESTRICT v, 365 int src_width, int do_store); 366 extern void WebPConvertRGBA32ToUV_C(const uint16_t* WEBP_RESTRICT rgb, 367 uint8_t* WEBP_RESTRICT u, 368 uint8_t* WEBP_RESTRICT v, int width); 369 370 // Must be called before using the above. 371 void WebPInitConvertARGBToYUV(void); 372 373 //------------------------------------------------------------------------------ 374 // Rescaler 375 376 struct WebPRescaler; 377 378 // Import a row of data and save its contribution in the rescaler. 379 // 'channel' denotes the channel number to be imported. 'Expand' corresponds to 380 // the wrk->x_expand case. Otherwise, 'Shrink' is to be used. 381 typedef void (*WebPRescalerImportRowFunc)( 382 struct WebPRescaler* WEBP_RESTRICT const wrk, 383 const uint8_t* WEBP_RESTRICT src); 384 385 extern WebPRescalerImportRowFunc WebPRescalerImportRowExpand; 386 extern WebPRescalerImportRowFunc WebPRescalerImportRowShrink; 387 388 // Export one row (starting at x_out position) from rescaler. 389 // 'Expand' corresponds to the wrk->y_expand case. 390 // Otherwise 'Shrink' is to be used 391 typedef void (*WebPRescalerExportRowFunc)(struct WebPRescaler* const wrk); 392 extern WebPRescalerExportRowFunc WebPRescalerExportRowExpand; 393 extern WebPRescalerExportRowFunc WebPRescalerExportRowShrink; 394 395 // Plain-C implementation, as fall-back. 396 extern void WebPRescalerImportRowExpand_C( 397 struct WebPRescaler* WEBP_RESTRICT const wrk, 398 const uint8_t* WEBP_RESTRICT src); 399 extern void WebPRescalerImportRowShrink_C( 400 struct WebPRescaler* WEBP_RESTRICT const wrk, 401 const uint8_t* WEBP_RESTRICT src); 402 extern void WebPRescalerExportRowExpand_C(struct WebPRescaler* const wrk); 403 extern void WebPRescalerExportRowShrink_C(struct WebPRescaler* const wrk); 404 405 // Main entry calls: 406 extern void WebPRescalerImportRow( 407 struct WebPRescaler* WEBP_RESTRICT const wrk, 408 const uint8_t* WEBP_RESTRICT src); 409 // Export one row (starting at x_out position) from rescaler. 410 extern void WebPRescalerExportRow(struct WebPRescaler* const wrk); 411 412 // Must be called first before using the above. 413 void WebPRescalerDspInit(void); 414 415 //------------------------------------------------------------------------------ 416 // Utilities for processing transparent channel. 417 418 // Apply alpha pre-multiply on an rgba, bgra or argb plane of size w * h. 419 // alpha_first should be 0 for argb, 1 for rgba or bgra (where alpha is last). 420 extern void (*WebPApplyAlphaMultiply)( 421 uint8_t* rgba, int alpha_first, int w, int h, int stride); 422 423 // Same, buf specifically for RGBA4444 format 424 extern void (*WebPApplyAlphaMultiply4444)( 425 uint8_t* rgba4444, int w, int h, int stride); 426 427 // Dispatch the values from alpha[] plane to the ARGB destination 'dst'. 428 // Returns true if alpha[] plane has non-trivial values different from 0xff. 429 extern int (*WebPDispatchAlpha)(const uint8_t* WEBP_RESTRICT alpha, 430 int alpha_stride, int width, int height, 431 uint8_t* WEBP_RESTRICT dst, int dst_stride); 432 433 // Transfer packed 8b alpha[] values to green channel in dst[], zero'ing the 434 // A/R/B values. 'dst_stride' is the stride for dst[] in uint32_t units. 435 extern void (*WebPDispatchAlphaToGreen)(const uint8_t* WEBP_RESTRICT alpha, 436 int alpha_stride, int width, int height, 437 uint32_t* WEBP_RESTRICT dst, 438 int dst_stride); 439 440 // Extract the alpha values from 32b values in argb[] and pack them into alpha[] 441 // (this is the opposite of WebPDispatchAlpha). 442 // Returns true if there's only trivial 0xff alpha values. 443 extern int (*WebPExtractAlpha)(const uint8_t* WEBP_RESTRICT argb, 444 int argb_stride, int width, int height, 445 uint8_t* WEBP_RESTRICT alpha, 446 int alpha_stride); 447 448 // Extract the green values from 32b values in argb[] and pack them into alpha[] 449 // (this is the opposite of WebPDispatchAlphaToGreen). 450 extern void (*WebPExtractGreen)(const uint32_t* WEBP_RESTRICT argb, 451 uint8_t* WEBP_RESTRICT alpha, int size); 452 453 // Pre-Multiply operation transforms x into x * A / 255 (where x=Y,R,G or B). 454 // Un-Multiply operation transforms x into x * 255 / A. 455 456 // Pre-Multiply or Un-Multiply (if 'inverse' is true) argb values in a row. 457 extern void (*WebPMultARGBRow)(uint32_t* const ptr, int width, int inverse); 458 459 // Same a WebPMultARGBRow(), but for several rows. 460 void WebPMultARGBRows(uint8_t* ptr, int stride, int width, int num_rows, 461 int inverse); 462 463 // Same for a row of single values, with side alpha values. 464 extern void (*WebPMultRow)(uint8_t* WEBP_RESTRICT const ptr, 465 const uint8_t* WEBP_RESTRICT const alpha, 466 int width, int inverse); 467 468 // Same a WebPMultRow(), but for several 'num_rows' rows. 469 void WebPMultRows(uint8_t* WEBP_RESTRICT ptr, int stride, 470 const uint8_t* WEBP_RESTRICT alpha, int alpha_stride, 471 int width, int num_rows, int inverse); 472 473 // Plain-C versions, used as fallback by some implementations. 474 void WebPMultRow_C(uint8_t* WEBP_RESTRICT const ptr, 475 const uint8_t* WEBP_RESTRICT const alpha, 476 int width, int inverse); 477 void WebPMultARGBRow_C(uint32_t* const ptr, int width, int inverse); 478 479 #ifdef WORDS_BIGENDIAN 480 // ARGB packing function: a/r/g/b input is rgba or bgra order. 481 extern void (*WebPPackARGB)(const uint8_t* WEBP_RESTRICT a, 482 const uint8_t* WEBP_RESTRICT r, 483 const uint8_t* WEBP_RESTRICT g, 484 const uint8_t* WEBP_RESTRICT b, 485 int len, uint32_t* WEBP_RESTRICT out); 486 #endif 487 488 // RGB packing function. 'step' can be 3 or 4. r/g/b input is rgb or bgr order. 489 extern void (*WebPPackRGB)(const uint8_t* WEBP_RESTRICT r, 490 const uint8_t* WEBP_RESTRICT g, 491 const uint8_t* WEBP_RESTRICT b, 492 int len, int step, uint32_t* WEBP_RESTRICT out); 493 494 // This function returns true if src[i] contains a value different from 0xff. 495 extern int (*WebPHasAlpha8b)(const uint8_t* src, int length); 496 // This function returns true if src[4*i] contains a value different from 0xff. 497 extern int (*WebPHasAlpha32b)(const uint8_t* src, int length); 498 // replaces transparent values in src[] by 'color'. 499 extern void (*WebPAlphaReplace)(uint32_t* src, int length, uint32_t color); 500 501 // To be called first before using the above. 502 void WebPInitAlphaProcessing(void); 503 504 //------------------------------------------------------------------------------ 505 // Filter functions 506 507 typedef enum { // Filter types. 508 WEBP_FILTER_NONE = 0, 509 WEBP_FILTER_HORIZONTAL, 510 WEBP_FILTER_VERTICAL, 511 WEBP_FILTER_GRADIENT, 512 WEBP_FILTER_LAST = WEBP_FILTER_GRADIENT + 1, // end marker 513 WEBP_FILTER_BEST, // meta-types 514 WEBP_FILTER_FAST 515 } WEBP_FILTER_TYPE; 516 517 typedef void (*WebPFilterFunc)(const uint8_t* WEBP_RESTRICT in, 518 int width, int height, int stride, 519 uint8_t* WEBP_RESTRICT out); 520 // In-place un-filtering. 521 // Warning! 'prev_line' pointer can be equal to 'cur_line' or 'preds'. 522 typedef void (*WebPUnfilterFunc)(const uint8_t* prev_line, const uint8_t* preds, 523 uint8_t* cur_line, int width); 524 525 // Filter the given data using the given predictor. 526 // 'in' corresponds to a 2-dimensional pixel array of size (stride * height) 527 // in raster order. 528 // 'stride' is number of bytes per scan line (with possible padding). 529 // 'out' should be pre-allocated. 530 extern WebPFilterFunc WebPFilters[WEBP_FILTER_LAST]; 531 532 // In-place reconstruct the original data from the given filtered data. 533 // The reconstruction will be done for 'num_rows' rows starting from 'row' 534 // (assuming rows upto 'row - 1' are already reconstructed). 535 extern WebPUnfilterFunc WebPUnfilters[WEBP_FILTER_LAST]; 536 537 // To be called first before using the above. 538 void VP8FiltersInit(void); 539 540 #ifdef __cplusplus 541 } // extern "C" 542 #endif 543 544 #endif // WEBP_DSP_DSP_H_