// Copyright 2011 Google Inc. All Rights Reserved. // // Use of this source code is governed by a BSD-style license // that can be found in the COPYING file in the root of the source // tree. An additional intellectual property rights grant can be found // in the file PATENTS. All contributing project authors may // be found in the AUTHORS file in the root of the source tree. // ----------------------------------------------------------------------------- // // WebP encoder: internal header. // // Author: Skal (pascal.massimino@gmail.com) #ifndef WEBP_ENC_VP8I_ENC_H_ #define WEBP_ENC_VP8I_ENC_H_ #include // for memcpy() #include "src/dec/common_dec.h" #include "src/dsp/dsp.h" #include "src/utils/bit_writer_utils.h" #include "src/utils/thread_utils.h" #include "src/utils/utils.h" #include "src/webp/encode.h" #ifdef __cplusplus extern "C" { #endif //------------------------------------------------------------------------------ // Various defines and enums // version numbers #define ENC_MAJ_VERSION 1 #define ENC_MIN_VERSION 2 #define ENC_REV_VERSION 4 enum { MAX_LF_LEVELS = 64, // Maximum loop filter level MAX_VARIABLE_LEVEL = 67, // last (inclusive) level with variable cost MAX_LEVEL = 2047 // max level (note: max codable is 2047 + 67) }; typedef enum { // Rate-distortion optimization levels RD_OPT_NONE = 0, // no rd-opt RD_OPT_BASIC = 1, // basic scoring (no trellis) RD_OPT_TRELLIS = 2, // perform trellis-quant on the final decision only RD_OPT_TRELLIS_ALL = 3 // trellis-quant for every scoring (much slower) } VP8RDLevel; // YUV-cache parameters. Cache is 32-bytes wide (= one cacheline). // The original or reconstructed samples can be accessed using VP8Scan[]. // The predicted blocks can be accessed using offsets to yuv_p_ and // the arrays VP8*ModeOffsets[]. // * YUV Samples area (yuv_in_/yuv_out_/yuv_out2_) // (see VP8Scan[] for accessing the blocks, along with // Y_OFF_ENC/U_OFF_ENC/V_OFF_ENC): // +----+----+ // Y_OFF_ENC |YYYY|UUVV| // U_OFF_ENC |YYYY|UUVV| // V_OFF_ENC |YYYY|....| <- 25% wasted U/V area // |YYYY|....| // +----+----+ // * Prediction area ('yuv_p_', size = PRED_SIZE_ENC) // Intra16 predictions (16x16 block each, two per row): // |I16DC16|I16TM16| // |I16VE16|I16HE16| // Chroma U/V predictions (16x8 block each, two per row): // |C8DC8|C8TM8| // |C8VE8|C8HE8| // Intra 4x4 predictions (4x4 block each) // |I4DC4 I4TM4 I4VE4 I4HE4|I4RD4 I4VR4 I4LD4 I4VL4| // |I4HD4 I4HU4 I4TMP .....|.......................| <- ~31% wasted #define YUV_SIZE_ENC (BPS * 16) #define PRED_SIZE_ENC (32 * BPS + 16 * BPS + 8 * BPS) // I16+Chroma+I4 preds #define Y_OFF_ENC (0) #define U_OFF_ENC (16) #define V_OFF_ENC (16 + 8) extern const uint16_t VP8Scan[16]; extern const uint16_t VP8UVModeOffsets[4]; extern const uint16_t VP8I16ModeOffsets[4]; extern const uint16_t VP8I4ModeOffsets[NUM_BMODES]; // Layout of prediction blocks // intra 16x16 #define I16DC16 (0 * 16 * BPS) #define I16TM16 (I16DC16 + 16) #define I16VE16 (1 * 16 * BPS) #define I16HE16 (I16VE16 + 16) // chroma 8x8, two U/V blocks side by side (hence: 16x8 each) #define C8DC8 (2 * 16 * BPS) #define C8TM8 (C8DC8 + 1 * 16) #define C8VE8 (2 * 16 * BPS + 8 * BPS) #define C8HE8 (C8VE8 + 1 * 16) // intra 4x4 #define I4DC4 (3 * 16 * BPS + 0) #define I4TM4 (I4DC4 + 4) #define I4VE4 (I4DC4 + 8) #define I4HE4 (I4DC4 + 12) #define I4RD4 (I4DC4 + 16) #define I4VR4 (I4DC4 + 20) #define I4LD4 (I4DC4 + 24) #define I4VL4 (I4DC4 + 28) #define I4HD4 (3 * 16 * BPS + 4 * BPS) #define I4HU4 (I4HD4 + 4) #define I4TMP (I4HD4 + 8) typedef int64_t score_t; // type used for scores, rate, distortion // Note that MAX_COST is not the maximum allowed by sizeof(score_t), // in order to allow overflowing computations. #define MAX_COST ((score_t)0x7fffffffffffffLL) #define QFIX 17 #define BIAS(b) ((b) << (QFIX - 8)) // Fun fact: this is the _only_ line where we're actually being lossy and // discarding bits. static WEBP_INLINE int QUANTDIV(uint32_t n, uint32_t iQ, uint32_t B) { return (int)((n * iQ + B) >> QFIX); } // Uncomment the following to remove token-buffer code: // #define DISABLE_TOKEN_BUFFER // quality below which error-diffusion is enabled #define ERROR_DIFFUSION_QUALITY 98 //------------------------------------------------------------------------------ // Headers typedef uint32_t proba_t; // 16b + 16b typedef uint8_t ProbaArray[NUM_CTX][NUM_PROBAS]; typedef proba_t StatsArray[NUM_CTX][NUM_PROBAS]; typedef uint16_t CostArray[NUM_CTX][MAX_VARIABLE_LEVEL + 1]; typedef const uint16_t* (*CostArrayPtr)[NUM_CTX]; // for easy casting typedef const uint16_t* CostArrayMap[16][NUM_CTX]; typedef double LFStats[NUM_MB_SEGMENTS][MAX_LF_LEVELS]; // filter stats typedef struct VP8Encoder VP8Encoder; // segment features typedef struct { int num_segments_; // Actual number of segments. 1 segment only = unused. int update_map_; // whether to update the segment map or not. // must be 0 if there's only 1 segment. int size_; // bit-cost for transmitting the segment map } VP8EncSegmentHeader; // Struct collecting all frame-persistent probabilities. typedef struct { uint8_t segments_[3]; // probabilities for segment tree uint8_t skip_proba_; // final probability of being skipped. ProbaArray coeffs_[NUM_TYPES][NUM_BANDS]; // 1056 bytes StatsArray stats_[NUM_TYPES][NUM_BANDS]; // 4224 bytes CostArray level_cost_[NUM_TYPES][NUM_BANDS]; // 13056 bytes CostArrayMap remapped_costs_[NUM_TYPES]; // 1536 bytes int dirty_; // if true, need to call VP8CalculateLevelCosts() int use_skip_proba_; // Note: we always use skip_proba for now. int nb_skip_; // number of skipped blocks } VP8EncProba; // Filter parameters. Not actually used in the code (we don't perform // the in-loop filtering), but filled from user's config typedef struct { int simple_; // filtering type: 0=complex, 1=simple int level_; // base filter level [0..63] int sharpness_; // [0..7] int i4x4_lf_delta_; // delta filter level for i4x4 relative to i16x16 } VP8EncFilterHeader; //------------------------------------------------------------------------------ // Informations about the macroblocks. typedef struct { // block type unsigned int type_:2; // 0=i4x4, 1=i16x16 unsigned int uv_mode_:2; unsigned int skip_:1; unsigned int segment_:2; uint8_t alpha_; // quantization-susceptibility } VP8MBInfo; typedef struct VP8Matrix { uint16_t q_[16]; // quantizer steps uint16_t iq_[16]; // reciprocals, fixed point. uint32_t bias_[16]; // rounding bias uint32_t zthresh_[16]; // value below which a coefficient is zeroed uint16_t sharpen_[16]; // frequency boosters for slight sharpening } VP8Matrix; typedef struct { VP8Matrix y1_, y2_, uv_; // quantization matrices int alpha_; // quant-susceptibility, range [-127,127]. Zero is neutral. // Lower values indicate a lower risk of blurriness. int beta_; // filter-susceptibility, range [0,255]. int quant_; // final segment quantizer. int fstrength_; // final in-loop filtering strength int max_edge_; // max edge delta (for filtering strength) int min_disto_; // minimum distortion required to trigger filtering record // reactivities int lambda_i16_, lambda_i4_, lambda_uv_; int lambda_mode_, lambda_trellis_, tlambda_; int lambda_trellis_i16_, lambda_trellis_i4_, lambda_trellis_uv_; // lambda values for distortion-based evaluation score_t i4_penalty_; // penalty for using Intra4 } VP8SegmentInfo; typedef int8_t DError[2 /* u/v */][2 /* top or left */]; // Handy transient struct to accumulate score and info during RD-optimization // and mode evaluation. typedef struct { score_t D, SD; // Distortion, spectral distortion score_t H, R, score; // header bits, rate, score. int16_t y_dc_levels[16]; // Quantized levels for luma-DC, luma-AC, chroma. int16_t y_ac_levels[16][16]; int16_t uv_levels[4 + 4][16]; int mode_i16; // mode number for intra16 prediction uint8_t modes_i4[16]; // mode numbers for intra4 predictions int mode_uv; // mode number of chroma prediction uint32_t nz; // non-zero blocks int8_t derr[2][3]; // DC diffusion errors for U/V for blocks #1/2/3 } VP8ModeScore; // Iterator structure to iterate through macroblocks, pointing to the // right neighbouring data (samples, predictions, contexts, ...) typedef struct { int x_, y_; // current macroblock uint8_t* yuv_in_; // input samples uint8_t* yuv_out_; // output samples uint8_t* yuv_out2_; // secondary buffer swapped with yuv_out_. uint8_t* yuv_p_; // scratch buffer for prediction VP8Encoder* enc_; // back-pointer VP8MBInfo* mb_; // current macroblock VP8BitWriter* bw_; // current bit-writer uint8_t* preds_; // intra mode predictors (4x4 blocks) uint32_t* nz_; // non-zero pattern uint8_t i4_boundary_[37]; // 32+5 boundary samples needed by intra4x4 uint8_t* i4_top_; // pointer to the current top boundary sample int i4_; // current intra4x4 mode being tested int top_nz_[9]; // top-non-zero context. int left_nz_[9]; // left-non-zero. left_nz[8] is independent. uint64_t bit_count_[4][3]; // bit counters for coded levels. uint64_t luma_bits_; // macroblock bit-cost for luma uint64_t uv_bits_; // macroblock bit-cost for chroma LFStats* lf_stats_; // filter stats (borrowed from enc_) int do_trellis_; // if true, perform extra level optimisation int count_down_; // number of mb still to be processed int count_down0_; // starting counter value (for progress) int percent0_; // saved initial progress percent DError left_derr_; // left error diffusion (u/v) DError* top_derr_; // top diffusion error - NULL if disabled uint8_t* y_left_; // left luma samples (addressable from index -1 to 15). uint8_t* u_left_; // left u samples (addressable from index -1 to 7) uint8_t* v_left_; // left v samples (addressable from index -1 to 7) uint8_t* y_top_; // top luma samples at position 'x_' uint8_t* uv_top_; // top u/v samples at position 'x_', packed as 16 bytes // memory for storing y/u/v_left_ uint8_t yuv_left_mem_[17 + 16 + 16 + 8 + WEBP_ALIGN_CST]; // memory for yuv_* uint8_t yuv_mem_[3 * YUV_SIZE_ENC + PRED_SIZE_ENC + WEBP_ALIGN_CST]; } VP8EncIterator; // in iterator.c // must be called first void VP8IteratorInit(VP8Encoder* const enc, VP8EncIterator* const it); // restart a scan void VP8IteratorReset(VP8EncIterator* const it); // reset iterator position to row 'y' void VP8IteratorSetRow(VP8EncIterator* const it, int y); // set count down (=number of iterations to go) void VP8IteratorSetCountDown(VP8EncIterator* const it, int count_down); // return true if iteration is finished int VP8IteratorIsDone(const VP8EncIterator* const it); // Import uncompressed samples from source. // If tmp_32 is not NULL, import boundary samples too. // tmp_32 is a 32-bytes scratch buffer that must be aligned in memory. void VP8IteratorImport(VP8EncIterator* const it, uint8_t* const tmp_32); // export decimated samples void VP8IteratorExport(const VP8EncIterator* const it); // go to next macroblock. Returns false if not finished. int VP8IteratorNext(VP8EncIterator* const it); // save the yuv_out_ boundary values to top_/left_ arrays for next iterations. void VP8IteratorSaveBoundary(VP8EncIterator* const it); // Report progression based on macroblock rows. Return 0 for user-abort request. int VP8IteratorProgress(const VP8EncIterator* const it, int delta); // Intra4x4 iterations void VP8IteratorStartI4(VP8EncIterator* const it); // returns true if not done. int VP8IteratorRotateI4(VP8EncIterator* const it, const uint8_t* const yuv_out); // Non-zero context setup/teardown void VP8IteratorNzToBytes(VP8EncIterator* const it); void VP8IteratorBytesToNz(VP8EncIterator* const it); // Helper functions to set mode properties void VP8SetIntra16Mode(const VP8EncIterator* const it, int mode); void VP8SetIntra4Mode(const VP8EncIterator* const it, const uint8_t* modes); void VP8SetIntraUVMode(const VP8EncIterator* const it, int mode); void VP8SetSkip(const VP8EncIterator* const it, int skip); void VP8SetSegment(const VP8EncIterator* const it, int segment); //------------------------------------------------------------------------------ // Paginated token buffer typedef struct VP8Tokens VP8Tokens; // struct details in token.c typedef struct { #if !defined(DISABLE_TOKEN_BUFFER) VP8Tokens* pages_; // first page VP8Tokens** last_page_; // last page uint16_t* tokens_; // set to (*last_page_)->tokens_ int left_; // how many free tokens left before the page is full int page_size_; // number of tokens per page #endif int error_; // true in case of malloc error } VP8TBuffer; // initialize an empty buffer void VP8TBufferInit(VP8TBuffer* const b, int page_size); void VP8TBufferClear(VP8TBuffer* const b); // de-allocate pages memory #if !defined(DISABLE_TOKEN_BUFFER) // Finalizes bitstream when probabilities are known. // Deletes the allocated token memory if final_pass is true. int VP8EmitTokens(VP8TBuffer* const b, VP8BitWriter* const bw, const uint8_t* const probas, int final_pass); // record the coding of coefficients without knowing the probabilities yet int VP8RecordCoeffTokens(int ctx, const struct VP8Residual* const res, VP8TBuffer* const tokens); // Estimate the final coded size given a set of 'probas'. size_t VP8EstimateTokenSize(VP8TBuffer* const b, const uint8_t* const probas); #endif // !DISABLE_TOKEN_BUFFER //------------------------------------------------------------------------------ // VP8Encoder struct VP8Encoder { const WebPConfig* config_; // user configuration and parameters WebPPicture* pic_; // input / output picture // headers VP8EncFilterHeader filter_hdr_; // filtering information VP8EncSegmentHeader segment_hdr_; // segment information int profile_; // VP8's profile, deduced from Config. // dimension, in macroblock units. int mb_w_, mb_h_; int preds_w_; // stride of the *preds_ prediction plane (=4*mb_w + 1) // number of partitions (1, 2, 4 or 8 = MAX_NUM_PARTITIONS) int num_parts_; // per-partition boolean decoders. VP8BitWriter bw_; // part0 VP8BitWriter parts_[MAX_NUM_PARTITIONS]; // token partitions VP8TBuffer tokens_; // token buffer int percent_; // for progress // transparency blob int has_alpha_; uint8_t* alpha_data_; // non-NULL if transparency is present uint32_t alpha_data_size_; WebPWorker alpha_worker_; // quantization info (one set of DC/AC dequant factor per segment) VP8SegmentInfo dqm_[NUM_MB_SEGMENTS]; int base_quant_; // nominal quantizer value. Only used // for relative coding of segments' quant. int alpha_; // global susceptibility (<=> complexity) int uv_alpha_; // U/V quantization susceptibility // global offset of quantizers, shared by all segments int dq_y1_dc_; int dq_y2_dc_, dq_y2_ac_; int dq_uv_dc_, dq_uv_ac_; // probabilities and statistics VP8EncProba proba_; uint64_t sse_[4]; // sum of Y/U/V/A squared errors for all macroblocks uint64_t sse_count_; // pixel count for the sse_[] stats int coded_size_; int residual_bytes_[3][4]; int block_count_[3]; // quality/speed settings int method_; // 0=fastest, 6=best/slowest. VP8RDLevel rd_opt_level_; // Deduced from method_. int max_i4_header_bits_; // partition #0 safeness factor int mb_header_limit_; // rough limit for header bits per MB int thread_level_; // derived from config->thread_level int do_search_; // derived from config->target_XXX int use_tokens_; // if true, use token buffer // Memory VP8MBInfo* mb_info_; // contextual macroblock infos (mb_w_ + 1) uint8_t* preds_; // predictions modes: (4*mb_w+1) * (4*mb_h+1) uint32_t* nz_; // non-zero bit context: mb_w+1 uint8_t* y_top_; // top luma samples. uint8_t* uv_top_; // top u/v samples. // U and V are packed into 16 bytes (8 U + 8 V) LFStats* lf_stats_; // autofilter stats (if NULL, autofilter is off) DError* top_derr_; // diffusion error (NULL if disabled) }; //------------------------------------------------------------------------------ // internal functions. Not public. // in tree.c extern const uint8_t VP8CoeffsProba0[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS]; extern const uint8_t VP8CoeffsUpdateProba[NUM_TYPES][NUM_BANDS][NUM_CTX][NUM_PROBAS]; // Reset the token probabilities to their initial (default) values void VP8DefaultProbas(VP8Encoder* const enc); // Write the token probabilities void VP8WriteProbas(VP8BitWriter* const bw, const VP8EncProba* const probas); // Writes the partition #0 modes (that is: all intra modes) void VP8CodeIntraModes(VP8Encoder* const enc); // in syntax.c // Generates the final bitstream by coding the partition0 and headers, // and appending an assembly of all the pre-coded token partitions. // Return true if everything is ok. int VP8EncWrite(VP8Encoder* const enc); // Release memory allocated for bit-writing in VP8EncLoop & seq. void VP8EncFreeBitWriters(VP8Encoder* const enc); // in frame.c extern const uint8_t VP8Cat3[]; extern const uint8_t VP8Cat4[]; extern const uint8_t VP8Cat5[]; extern const uint8_t VP8Cat6[]; // Form all the four Intra16x16 predictions in the yuv_p_ cache void VP8MakeLuma16Preds(const VP8EncIterator* const it); // Form all the four Chroma8x8 predictions in the yuv_p_ cache void VP8MakeChroma8Preds(const VP8EncIterator* const it); // Form all the ten Intra4x4 predictions in the yuv_p_ cache // for the 4x4 block it->i4_ void VP8MakeIntra4Preds(const VP8EncIterator* const it); // Rate calculation int VP8GetCostLuma16(VP8EncIterator* const it, const VP8ModeScore* const rd); int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]); int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd); // Main coding calls int VP8EncLoop(VP8Encoder* const enc); int VP8EncTokenLoop(VP8Encoder* const enc); // in webpenc.c // Assign an error code to a picture. Return false for convenience. int WebPEncodingSetError(const WebPPicture* const pic, WebPEncodingError error); int WebPReportProgress(const WebPPicture* const pic, int percent, int* const percent_store); // in analysis.c // Main analysis loop. Decides the segmentations and complexity. // Assigns a first guess for Intra16 and uvmode_ prediction modes. int VP8EncAnalyze(VP8Encoder* const enc); // in quant.c // Sets up segment's quantization values, base_quant_ and filter strengths. void VP8SetSegmentParams(VP8Encoder* const enc, float quality); // Pick best modes and fills the levels. Returns true if skipped. int VP8Decimate(VP8EncIterator* WEBP_RESTRICT const it, VP8ModeScore* WEBP_RESTRICT const rd, VP8RDLevel rd_opt); // in alpha.c void VP8EncInitAlpha(VP8Encoder* const enc); // initialize alpha compression int VP8EncStartAlpha(VP8Encoder* const enc); // start alpha coding process int VP8EncFinishAlpha(VP8Encoder* const enc); // finalize compressed data int VP8EncDeleteAlpha(VP8Encoder* const enc); // delete compressed data // autofilter void VP8InitFilter(VP8EncIterator* const it); void VP8StoreFilterStats(VP8EncIterator* const it); void VP8AdjustFilterStrength(VP8EncIterator* const it); // returns the approximate filtering strength needed to smooth a edge // step of 'delta', given a sharpness parameter 'sharpness'. int VP8FilterStrengthFromDelta(int sharpness, int delta); // misc utils for picture_*.c: // Returns true if 'picture' is non-NULL and dimensions/colorspace are within // their valid ranges. If returning false, the 'error_code' in 'picture' is // updated. int WebPValidatePicture(const WebPPicture* const picture); // Remove reference to the ARGB/YUVA buffer (doesn't free anything). void WebPPictureResetBuffers(WebPPicture* const picture); // Allocates ARGB buffer according to set width/height (previous one is // always free'd). Preserves the YUV(A) buffer. Returns false in case of error // (invalid param, out-of-memory). int WebPPictureAllocARGB(WebPPicture* const picture); // Allocates YUVA buffer according to set width/height (previous one is always // free'd). Uses picture->csp to determine whether an alpha buffer is needed. // Preserves the ARGB buffer. // Returns false in case of error (invalid param, out-of-memory). int WebPPictureAllocYUVA(WebPPicture* const picture); // Replace samples that are fully transparent by 'color' to help compressibility // (no guarantee, though). Assumes pic->use_argb is true. void WebPReplaceTransparentPixels(WebPPicture* const pic, uint32_t color); //------------------------------------------------------------------------------ #ifdef __cplusplus } // extern "C" #endif #endif // WEBP_ENC_VP8I_ENC_H_