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 // WebP encoder: internal header. 11 // 12 // Author: Skal (pascal.massimino (at) gmail.com) 13 14 #ifndef WEBP_ENC_VP8ENCI_H_ 15 #define WEBP_ENC_VP8ENCI_H_ 16 17 #include <string.h> // for memcpy() 18 #include "webp/encode.h" 19 #include "../dsp/dsp.h" 20 #include "../utils/bit_writer.h" 21 #include "../utils/thread.h" 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 //------------------------------------------------------------------------------ 28 // Various defines and enums 29 30 // version numbers 31 #define ENC_MAJ_VERSION 0 32 #define ENC_MIN_VERSION 4 33 #define ENC_REV_VERSION 2 34 35 // intra prediction modes 36 enum { B_DC_PRED = 0, // 4x4 modes 37 B_TM_PRED = 1, 38 B_VE_PRED = 2, 39 B_HE_PRED = 3, 40 B_RD_PRED = 4, 41 B_VR_PRED = 5, 42 B_LD_PRED = 6, 43 B_VL_PRED = 7, 44 B_HD_PRED = 8, 45 B_HU_PRED = 9, 46 NUM_BMODES = B_HU_PRED + 1 - B_DC_PRED, // = 10 47 48 // Luma16 or UV modes 49 DC_PRED = B_DC_PRED, V_PRED = B_VE_PRED, 50 H_PRED = B_HE_PRED, TM_PRED = B_TM_PRED, 51 NUM_PRED_MODES = 4 52 }; 53 54 enum { NUM_MB_SEGMENTS = 4, 55 MAX_NUM_PARTITIONS = 8, 56 NUM_TYPES = 4, // 0: i16-AC, 1: i16-DC, 2:chroma-AC, 3:i4-AC 57 NUM_BANDS = 8, 58 NUM_CTX = 3, 59 NUM_PROBAS = 11, 60 MAX_LF_LEVELS = 64, // Maximum loop filter level 61 MAX_VARIABLE_LEVEL = 67, // last (inclusive) level with variable cost 62 MAX_LEVEL = 2047 // max level (note: max codable is 2047 + 67) 63 }; 64 65 typedef enum { // Rate-distortion optimization levels 66 RD_OPT_NONE = 0, // no rd-opt 67 RD_OPT_BASIC = 1, // basic scoring (no trellis) 68 RD_OPT_TRELLIS = 2, // perform trellis-quant on the final decision only 69 RD_OPT_TRELLIS_ALL = 3 // trellis-quant for every scoring (much slower) 70 } VP8RDLevel; 71 72 // YUV-cache parameters. Cache is 16-pixels wide. 73 // The original or reconstructed samples can be accessed using VP8Scan[] 74 // The predicted blocks can be accessed using offsets to yuv_p_ and 75 // the arrays VP8*ModeOffsets[]; 76 // +----+ YUV Samples area. See VP8Scan[] for accessing the blocks. 77 // Y_OFF |YYYY| <- original samples ('yuv_in_') 78 // |YYYY| 79 // |YYYY| 80 // |YYYY| 81 // U_OFF |UUVV| V_OFF (=U_OFF + 8) 82 // |UUVV| 83 // +----+ 84 // Y_OFF |YYYY| <- compressed/decoded samples ('yuv_out_') 85 // |YYYY| There are two buffers like this ('yuv_out_'/'yuv_out2_') 86 // |YYYY| 87 // |YYYY| 88 // U_OFF |UUVV| V_OFF 89 // |UUVV| 90 // x2 (for yuv_out2_) 91 // +----+ Prediction area ('yuv_p_', size = PRED_SIZE) 92 // I16DC16 |YYYY| Intra16 predictions (16x16 block each) 93 // |YYYY| 94 // |YYYY| 95 // |YYYY| 96 // I16TM16 |YYYY| 97 // |YYYY| 98 // |YYYY| 99 // |YYYY| 100 // I16VE16 |YYYY| 101 // |YYYY| 102 // |YYYY| 103 // |YYYY| 104 // I16HE16 |YYYY| 105 // |YYYY| 106 // |YYYY| 107 // |YYYY| 108 // +----+ Chroma U/V predictions (16x8 block each) 109 // C8DC8 |UUVV| 110 // |UUVV| 111 // C8TM8 |UUVV| 112 // |UUVV| 113 // C8VE8 |UUVV| 114 // |UUVV| 115 // C8HE8 |UUVV| 116 // |UUVV| 117 // +----+ Intra 4x4 predictions (4x4 block each) 118 // |YYYY| I4DC4 I4TM4 I4VE4 I4HE4 119 // |YYYY| I4RD4 I4VR4 I4LD4 I4VL4 120 // |YY..| I4HD4 I4HU4 I4TMP 121 // +----+ 122 #define BPS 16 // this is the common stride 123 #define Y_SIZE (BPS * 16) 124 #define UV_SIZE (BPS * 8) 125 #define YUV_SIZE (Y_SIZE + UV_SIZE) 126 #define PRED_SIZE (6 * 16 * BPS + 12 * BPS) 127 #define Y_OFF (0) 128 #define U_OFF (Y_SIZE) 129 #define V_OFF (U_OFF + 8) 130 #define ALIGN_CST 15 131 #define DO_ALIGN(PTR) ((uintptr_t)((PTR) + ALIGN_CST) & ~ALIGN_CST) 132 133 extern const int VP8Scan[16]; // in quant.c 134 extern const int VP8UVModeOffsets[4]; // in analyze.c 135 extern const int VP8I16ModeOffsets[4]; 136 extern const int VP8I4ModeOffsets[NUM_BMODES]; 137 138 // Layout of prediction blocks 139 // intra 16x16 140 #define I16DC16 (0 * 16 * BPS) 141 #define I16TM16 (1 * 16 * BPS) 142 #define I16VE16 (2 * 16 * BPS) 143 #define I16HE16 (3 * 16 * BPS) 144 // chroma 8x8, two U/V blocks side by side (hence: 16x8 each) 145 #define C8DC8 (4 * 16 * BPS) 146 #define C8TM8 (4 * 16 * BPS + 8 * BPS) 147 #define C8VE8 (5 * 16 * BPS) 148 #define C8HE8 (5 * 16 * BPS + 8 * BPS) 149 // intra 4x4 150 #define I4DC4 (6 * 16 * BPS + 0) 151 #define I4TM4 (6 * 16 * BPS + 4) 152 #define I4VE4 (6 * 16 * BPS + 8) 153 #define I4HE4 (6 * 16 * BPS + 12) 154 #define I4RD4 (6 * 16 * BPS + 4 * BPS + 0) 155 #define I4VR4 (6 * 16 * BPS + 4 * BPS + 4) 156 #define I4LD4 (6 * 16 * BPS + 4 * BPS + 8) 157 #define I4VL4 (6 * 16 * BPS + 4 * BPS + 12) 158 #define I4HD4 (6 * 16 * BPS + 8 * BPS + 0) 159 #define I4HU4 (6 * 16 * BPS + 8 * BPS + 4) 160 #define I4TMP (6 * 16 * BPS + 8 * BPS + 8) 161 162 typedef int64_t score_t; // type used for scores, rate, distortion 163 // Note that MAX_COST is not the maximum allowed by sizeof(score_t), 164 // in order to allow overflowing computations. 165 #define MAX_COST ((score_t)0x7fffffffffffffLL) 166 167 #define QFIX 17 168 #define BIAS(b) ((b) << (QFIX - 8)) 169 // Fun fact: this is the _only_ line where we're actually being lossy and 170 // discarding bits. 171 static WEBP_INLINE int QUANTDIV(uint32_t n, uint32_t iQ, uint32_t B) { 172 return (int)((n * iQ + B) >> QFIX); 173 } 174 175 // size of histogram used by CollectHistogram. 176 #define MAX_COEFF_THRESH 31 177 typedef struct VP8Histogram VP8Histogram; 178 struct VP8Histogram { 179 // TODO(skal): we only need to store the max_value and last_non_zero actually. 180 int distribution[MAX_COEFF_THRESH + 1]; 181 }; 182 183 // Uncomment the following to remove token-buffer code: 184 // #define DISABLE_TOKEN_BUFFER 185 186 //------------------------------------------------------------------------------ 187 // Headers 188 189 typedef uint32_t proba_t; // 16b + 16b 190 typedef uint8_t ProbaArray[NUM_CTX][NUM_PROBAS]; 191 typedef proba_t StatsArray[NUM_CTX][NUM_PROBAS]; 192 typedef uint16_t CostArray[NUM_CTX][MAX_VARIABLE_LEVEL + 1]; 193 typedef double LFStats[NUM_MB_SEGMENTS][MAX_LF_LEVELS]; // filter stats 194 195 typedef struct VP8Encoder VP8Encoder; 196 197 // segment features 198 typedef struct { 199 int num_segments_; // Actual number of segments. 1 segment only = unused. 200 int update_map_; // whether to update the segment map or not. 201 // must be 0 if there's only 1 segment. 202 int size_; // bit-cost for transmitting the segment map 203 } VP8SegmentHeader; 204 205 // Struct collecting all frame-persistent probabilities. 206 typedef struct { 207 uint8_t segments_[3]; // probabilities for segment tree 208 uint8_t skip_proba_; // final probability of being skipped. 209 ProbaArray coeffs_[NUM_TYPES][NUM_BANDS]; // 1056 bytes 210 StatsArray stats_[NUM_TYPES][NUM_BANDS]; // 4224 bytes 211 CostArray level_cost_[NUM_TYPES][NUM_BANDS]; // 13056 bytes 212 int dirty_; // if true, need to call VP8CalculateLevelCosts() 213 int use_skip_proba_; // Note: we always use skip_proba for now. 214 int nb_skip_; // number of skipped blocks 215 } VP8Proba; 216 217 // Filter parameters. Not actually used in the code (we don't perform 218 // the in-loop filtering), but filled from user's config 219 typedef struct { 220 int simple_; // filtering type: 0=complex, 1=simple 221 int level_; // base filter level [0..63] 222 int sharpness_; // [0..7] 223 int i4x4_lf_delta_; // delta filter level for i4x4 relative to i16x16 224 } VP8FilterHeader; 225 226 //------------------------------------------------------------------------------ 227 // Informations about the macroblocks. 228 229 typedef struct { 230 // block type 231 unsigned int type_:2; // 0=i4x4, 1=i16x16 232 unsigned int uv_mode_:2; 233 unsigned int skip_:1; 234 unsigned int segment_:2; 235 uint8_t alpha_; // quantization-susceptibility 236 } VP8MBInfo; 237 238 typedef struct VP8Matrix { 239 uint16_t q_[16]; // quantizer steps 240 uint16_t iq_[16]; // reciprocals, fixed point. 241 uint32_t bias_[16]; // rounding bias 242 uint32_t zthresh_[16]; // value below which a coefficient is zeroed 243 uint16_t sharpen_[16]; // frequency boosters for slight sharpening 244 } VP8Matrix; 245 246 typedef struct { 247 VP8Matrix y1_, y2_, uv_; // quantization matrices 248 int alpha_; // quant-susceptibility, range [-127,127]. Zero is neutral. 249 // Lower values indicate a lower risk of blurriness. 250 int beta_; // filter-susceptibility, range [0,255]. 251 int quant_; // final segment quantizer. 252 int fstrength_; // final in-loop filtering strength 253 int max_edge_; // max edge delta (for filtering strength) 254 int min_disto_; // minimum distortion required to trigger filtering record 255 // reactivities 256 int lambda_i16_, lambda_i4_, lambda_uv_; 257 int lambda_mode_, lambda_trellis_, tlambda_; 258 int lambda_trellis_i16_, lambda_trellis_i4_, lambda_trellis_uv_; 259 } VP8SegmentInfo; 260 261 // Handy transient struct to accumulate score and info during RD-optimization 262 // and mode evaluation. 263 typedef struct { 264 score_t D, SD; // Distortion, spectral distortion 265 score_t H, R, score; // header bits, rate, score. 266 int16_t y_dc_levels[16]; // Quantized levels for luma-DC, luma-AC, chroma. 267 int16_t y_ac_levels[16][16]; 268 int16_t uv_levels[4 + 4][16]; 269 int mode_i16; // mode number for intra16 prediction 270 uint8_t modes_i4[16]; // mode numbers for intra4 predictions 271 int mode_uv; // mode number of chroma prediction 272 uint32_t nz; // non-zero blocks 273 } VP8ModeScore; 274 275 // Iterator structure to iterate through macroblocks, pointing to the 276 // right neighbouring data (samples, predictions, contexts, ...) 277 typedef struct { 278 int x_, y_; // current macroblock 279 int y_stride_, uv_stride_; // respective strides 280 uint8_t* yuv_in_; // input samples 281 uint8_t* yuv_out_; // output samples 282 uint8_t* yuv_out2_; // secondary buffer swapped with yuv_out_. 283 uint8_t* yuv_p_; // scratch buffer for prediction 284 VP8Encoder* enc_; // back-pointer 285 VP8MBInfo* mb_; // current macroblock 286 VP8BitWriter* bw_; // current bit-writer 287 uint8_t* preds_; // intra mode predictors (4x4 blocks) 288 uint32_t* nz_; // non-zero pattern 289 uint8_t i4_boundary_[37]; // 32+5 boundary samples needed by intra4x4 290 uint8_t* i4_top_; // pointer to the current top boundary sample 291 int i4_; // current intra4x4 mode being tested 292 int top_nz_[9]; // top-non-zero context. 293 int left_nz_[9]; // left-non-zero. left_nz[8] is independent. 294 uint64_t bit_count_[4][3]; // bit counters for coded levels. 295 uint64_t luma_bits_; // macroblock bit-cost for luma 296 uint64_t uv_bits_; // macroblock bit-cost for chroma 297 LFStats* lf_stats_; // filter stats (borrowed from enc_) 298 int do_trellis_; // if true, perform extra level optimisation 299 int count_down_; // number of mb still to be processed 300 int count_down0_; // starting counter value (for progress) 301 int percent0_; // saved initial progress percent 302 303 uint8_t* y_left_; // left luma samples (addressable from index -1 to 15). 304 uint8_t* u_left_; // left u samples (addressable from index -1 to 7) 305 uint8_t* v_left_; // left v samples (addressable from index -1 to 7) 306 307 uint8_t* y_top_; // top luma samples at position 'x_' 308 uint8_t* uv_top_; // top u/v samples at position 'x_', packed as 16 bytes 309 310 // memory for storing y/u/v_left_ and yuv_in_/out_* 311 uint8_t yuv_left_mem_[17 + 16 + 16 + 8 + ALIGN_CST]; // memory for *_left_ 312 uint8_t yuv_mem_[3 * YUV_SIZE + PRED_SIZE + ALIGN_CST]; // memory for yuv_* 313 } VP8EncIterator; 314 315 // in iterator.c 316 // must be called first 317 void VP8IteratorInit(VP8Encoder* const enc, VP8EncIterator* const it); 318 // restart a scan 319 void VP8IteratorReset(VP8EncIterator* const it); 320 // reset iterator position to row 'y' 321 void VP8IteratorSetRow(VP8EncIterator* const it, int y); 322 // set count down (=number of iterations to go) 323 void VP8IteratorSetCountDown(VP8EncIterator* const it, int count_down); 324 // return true if iteration is finished 325 int VP8IteratorIsDone(const VP8EncIterator* const it); 326 // Import uncompressed samples from source. 327 // If tmp_32 is not NULL, import boundary samples too. 328 // tmp_32 is a 32-bytes scratch buffer that must be aligned in memory. 329 void VP8IteratorImport(VP8EncIterator* const it, uint8_t* tmp_32); 330 // export decimated samples 331 void VP8IteratorExport(const VP8EncIterator* const it); 332 // go to next macroblock. Returns false if not finished. 333 int VP8IteratorNext(VP8EncIterator* const it); 334 // save the yuv_out_ boundary values to top_/left_ arrays for next iterations. 335 void VP8IteratorSaveBoundary(VP8EncIterator* const it); 336 // Report progression based on macroblock rows. Return 0 for user-abort request. 337 int VP8IteratorProgress(const VP8EncIterator* const it, 338 int final_delta_percent); 339 // Intra4x4 iterations 340 void VP8IteratorStartI4(VP8EncIterator* const it); 341 // returns true if not done. 342 int VP8IteratorRotateI4(VP8EncIterator* const it, 343 const uint8_t* const yuv_out); 344 345 // Non-zero context setup/teardown 346 void VP8IteratorNzToBytes(VP8EncIterator* const it); 347 void VP8IteratorBytesToNz(VP8EncIterator* const it); 348 349 // Helper functions to set mode properties 350 void VP8SetIntra16Mode(const VP8EncIterator* const it, int mode); 351 void VP8SetIntra4Mode(const VP8EncIterator* const it, const uint8_t* modes); 352 void VP8SetIntraUVMode(const VP8EncIterator* const it, int mode); 353 void VP8SetSkip(const VP8EncIterator* const it, int skip); 354 void VP8SetSegment(const VP8EncIterator* const it, int segment); 355 356 //------------------------------------------------------------------------------ 357 // Paginated token buffer 358 359 typedef struct VP8Tokens VP8Tokens; // struct details in token.c 360 361 typedef struct { 362 #if !defined(DISABLE_TOKEN_BUFFER) 363 VP8Tokens* pages_; // first page 364 VP8Tokens** last_page_; // last page 365 uint16_t* tokens_; // set to (*last_page_)->tokens_ 366 int left_; // how many free tokens left before the page is full 367 int page_size_; // number of tokens per page 368 #endif 369 int error_; // true in case of malloc error 370 } VP8TBuffer; 371 372 // initialize an empty buffer 373 void VP8TBufferInit(VP8TBuffer* const b, int page_size); 374 void VP8TBufferClear(VP8TBuffer* const b); // de-allocate pages memory 375 376 #if !defined(DISABLE_TOKEN_BUFFER) 377 378 // Finalizes bitstream when probabilities are known. 379 // Deletes the allocated token memory if final_pass is true. 380 int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw, 381 const uint8_t* const probas, int final_pass); 382 383 // record the coding of coefficients without knowing the probabilities yet 384 int VP8RecordCoeffTokens(int ctx, int coeff_type, int first, int last, 385 const int16_t* const coeffs, 386 VP8TBuffer* const tokens); 387 388 // Estimate the final coded size given a set of 'probas'. 389 size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas); 390 391 // unused for now 392 void VP8TokenToStats(const VP8TBuffer* const b, proba_t* const stats); 393 394 #endif // !DISABLE_TOKEN_BUFFER 395 396 //------------------------------------------------------------------------------ 397 // VP8Encoder 398 399 struct VP8Encoder { 400 const WebPConfig* config_; // user configuration and parameters 401 WebPPicture* pic_; // input / output picture 402 403 // headers 404 VP8FilterHeader filter_hdr_; // filtering information 405 VP8SegmentHeader segment_hdr_; // segment information 406 407 int profile_; // VP8's profile, deduced from Config. 408 409 // dimension, in macroblock units. 410 int mb_w_, mb_h_; 411 int preds_w_; // stride of the *preds_ prediction plane (=4*mb_w + 1) 412 413 // number of partitions (1, 2, 4 or 8 = MAX_NUM_PARTITIONS) 414 int num_parts_; 415 416 // per-partition boolean decoders. 417 VP8BitWriter bw_; // part0 418 VP8BitWriter parts_[MAX_NUM_PARTITIONS]; // token partitions 419 VP8TBuffer tokens_; // token buffer 420 421 int percent_; // for progress 422 423 // transparency blob 424 int has_alpha_; 425 uint8_t* alpha_data_; // non-NULL if transparency is present 426 uint32_t alpha_data_size_; 427 WebPWorker alpha_worker_; 428 429 // quantization info (one set of DC/AC dequant factor per segment) 430 VP8SegmentInfo dqm_[NUM_MB_SEGMENTS]; 431 int base_quant_; // nominal quantizer value. Only used 432 // for relative coding of segments' quant. 433 int alpha_; // global susceptibility (<=> complexity) 434 int uv_alpha_; // U/V quantization susceptibility 435 // global offset of quantizers, shared by all segments 436 int dq_y1_dc_; 437 int dq_y2_dc_, dq_y2_ac_; 438 int dq_uv_dc_, dq_uv_ac_; 439 440 // probabilities and statistics 441 VP8Proba proba_; 442 uint64_t sse_[4]; // sum of Y/U/V/A squared errors for all macroblocks 443 uint64_t sse_count_; // pixel count for the sse_[] stats 444 int coded_size_; 445 int residual_bytes_[3][4]; 446 int block_count_[3]; 447 448 // quality/speed settings 449 int method_; // 0=fastest, 6=best/slowest. 450 VP8RDLevel rd_opt_level_; // Deduced from method_. 451 int max_i4_header_bits_; // partition #0 safeness factor 452 int thread_level_; // derived from config->thread_level 453 int do_search_; // derived from config->target_XXX 454 int use_tokens_; // if true, use token buffer 455 456 // Memory 457 VP8MBInfo* mb_info_; // contextual macroblock infos (mb_w_ + 1) 458 uint8_t* preds_; // predictions modes: (4*mb_w+1) * (4*mb_h+1) 459 uint32_t* nz_; // non-zero bit context: mb_w+1 460 uint8_t* y_top_; // top luma samples. 461 uint8_t* uv_top_; // top u/v samples. 462 // U and V are packed into 16 bytes (8 U + 8 V) 463 LFStats* lf_stats_; // autofilter stats (if NULL, autofilter is off) 464 }; 465 466 //------------------------------------------------------------------------------ 467 // internal functions. Not public. 468 469 // in tree.c 470 extern const uint8_t VP8CoeffsProba0[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS]; 471 extern const uint8_t 472 VP8CoeffsUpdateProba[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS]; 473 // Reset the token probabilities to their initial (default) values 474 void VP8DefaultProbas(VP8Encoder* const enc); 475 // Write the token probabilities 476 void VP8WriteProbas(VP8BitWriter* const bw, const VP8Proba* const probas); 477 // Writes the partition #0 modes (that is: all intra modes) 478 void VP8CodeIntraModes(VP8Encoder* const enc); 479 480 // in syntax.c 481 // Generates the final bitstream by coding the partition0 and headers, 482 // and appending an assembly of all the pre-coded token partitions. 483 // Return true if everything is ok. 484 int VP8EncWrite(VP8Encoder* const enc); 485 // Release memory allocated for bit-writing in VP8EncLoop & seq. 486 void VP8EncFreeBitWriters(VP8Encoder* const enc); 487 488 // in frame.c 489 extern const uint8_t VP8EncBands[16 + 1]; 490 extern const uint8_t VP8Cat3[]; 491 extern const uint8_t VP8Cat4[]; 492 extern const uint8_t VP8Cat5[]; 493 extern const uint8_t VP8Cat6[]; 494 495 // Form all the four Intra16x16 predictions in the yuv_p_ cache 496 void VP8MakeLuma16Preds(const VP8EncIterator* const it); 497 // Form all the four Chroma8x8 predictions in the yuv_p_ cache 498 void VP8MakeChroma8Preds(const VP8EncIterator* const it); 499 // Form all the ten Intra4x4 predictions in the yuv_p_ cache 500 // for the 4x4 block it->i4_ 501 void VP8MakeIntra4Preds(const VP8EncIterator* const it); 502 // Rate calculation 503 int VP8GetCostLuma16(VP8EncIterator* const it, const VP8ModeScore* const rd); 504 int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]); 505 int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd); 506 // Main coding calls 507 int VP8EncLoop(VP8Encoder* const enc); 508 int VP8EncTokenLoop(VP8Encoder* const enc); 509 510 // in webpenc.c 511 // Assign an error code to a picture. Return false for convenience. 512 int WebPEncodingSetError(const WebPPicture* const pic, WebPEncodingError error); 513 int WebPReportProgress(const WebPPicture* const pic, 514 int percent, int* const percent_store); 515 516 // in analysis.c 517 // Main analysis loop. Decides the segmentations and complexity. 518 // Assigns a first guess for Intra16 and uvmode_ prediction modes. 519 int VP8EncAnalyze(VP8Encoder* const enc); 520 521 // in quant.c 522 // Sets up segment's quantization values, base_quant_ and filter strengths. 523 void VP8SetSegmentParams(VP8Encoder* const enc, float quality); 524 // Pick best modes and fills the levels. Returns true if skipped. 525 int VP8Decimate(VP8EncIterator* const it, VP8ModeScore* const rd, 526 VP8RDLevel rd_opt); 527 528 // in alpha.c 529 void VP8EncInitAlpha(VP8Encoder* const enc); // initialize alpha compression 530 int VP8EncStartAlpha(VP8Encoder* const enc); // start alpha coding process 531 int VP8EncFinishAlpha(VP8Encoder* const enc); // finalize compressed data 532 int VP8EncDeleteAlpha(VP8Encoder* const enc); // delete compressed data 533 534 // in filter.c 535 536 // SSIM utils 537 typedef struct { 538 double w, xm, ym, xxm, xym, yym; 539 } DistoStats; 540 void VP8SSIMAddStats(const DistoStats* const src, DistoStats* const dst); 541 void VP8SSIMAccumulatePlane(const uint8_t* src1, int stride1, 542 const uint8_t* src2, int stride2, 543 int W, int H, DistoStats* const stats); 544 double VP8SSIMGet(const DistoStats* const stats); 545 double VP8SSIMGetSquaredError(const DistoStats* const stats); 546 547 // autofilter 548 void VP8InitFilter(VP8EncIterator* const it); 549 void VP8StoreFilterStats(VP8EncIterator* const it); 550 void VP8AdjustFilterStrength(VP8EncIterator* const it); 551 552 // returns the approximate filtering strength needed to smooth a edge 553 // step of 'delta', given a sharpness parameter 'sharpness'. 554 int VP8FilterStrengthFromDelta(int sharpness, int delta); 555 556 // misc utils for picture_*.c: 557 558 // Remove reference to the ARGB/YUVA buffer (doesn't free anything). 559 void WebPPictureResetBuffers(WebPPicture* const picture); 560 561 // Allocates ARGB buffer of given dimension (previous one is always free'd). 562 // Preserves the YUV(A) buffer. Returns false in case of error (invalid param, 563 // out-of-memory). 564 int WebPPictureAllocARGB(WebPPicture* const picture, int width, int height); 565 566 // Allocates YUVA buffer of given dimension (previous one is always free'd). 567 // Uses picture->csp to determine whether an alpha buffer is needed. 568 // Preserves the ARGB buffer. 569 // Returns false in case of error (invalid param, out-of-memory). 570 int WebPPictureAllocYUVA(WebPPicture* const picture, int width, int height); 571 572 //------------------------------------------------------------------------------ 573 574 #if WEBP_ENCODER_ABI_VERSION <= 0x0203 575 void WebPMemoryWriterClear(WebPMemoryWriter* writer); 576 #endif 577 578 #ifdef __cplusplus 579 } // extern "C" 580 #endif 581 582 #endif /* WEBP_ENC_VP8ENCI_H_ */ 583
