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Diffstat (limited to 'drivers/webpold/enc/quant.c')
| -rw-r--r-- | drivers/webpold/enc/quant.c | 930 |
1 files changed, 0 insertions, 930 deletions
diff --git a/drivers/webpold/enc/quant.c b/drivers/webpold/enc/quant.c deleted file mode 100644 index ea153849c8..0000000000 --- a/drivers/webpold/enc/quant.c +++ /dev/null @@ -1,930 +0,0 @@ -// Copyright 2011 Google Inc. All Rights Reserved. -// -// This code is licensed under the same terms as WebM: -// Software License Agreement: http://www.webmproject.org/license/software/ -// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ -// ----------------------------------------------------------------------------- -// -// Quantization -// -// Author: Skal (pascal.massimino@gmail.com) - -#include <assert.h> -#include <math.h> - -#include "./vp8enci.h" -#include "./cost.h" - -#define DO_TRELLIS_I4 1 -#define DO_TRELLIS_I16 1 // not a huge gain, but ok at low bitrate. -#define DO_TRELLIS_UV 0 // disable trellis for UV. Risky. Not worth. -#define USE_TDISTO 1 - -#define MID_ALPHA 64 // neutral value for susceptibility -#define MIN_ALPHA 30 // lowest usable value for susceptibility -#define MAX_ALPHA 100 // higher meaninful value for susceptibility - -#define SNS_TO_DQ 0.9 // Scaling constant between the sns value and the QP - // power-law modulation. Must be strictly less than 1. - -#define MULT_8B(a, b) (((a) * (b) + 128) >> 8) - -#if defined(__cplusplus) || defined(c_plusplus) -extern "C" { -#endif - -//------------------------------------------------------------------------------ - -static WEBP_INLINE int clip(int v, int m, int M) { - return v < m ? m : v > M ? M : v; -} - -static const uint8_t kZigzag[16] = { - 0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15 -}; - -static const uint8_t kDcTable[128] = { - 4, 5, 6, 7, 8, 9, 10, 10, - 11, 12, 13, 14, 15, 16, 17, 17, - 18, 19, 20, 20, 21, 21, 22, 22, - 23, 23, 24, 25, 25, 26, 27, 28, - 29, 30, 31, 32, 33, 34, 35, 36, - 37, 37, 38, 39, 40, 41, 42, 43, - 44, 45, 46, 46, 47, 48, 49, 50, - 51, 52, 53, 54, 55, 56, 57, 58, - 59, 60, 61, 62, 63, 64, 65, 66, - 67, 68, 69, 70, 71, 72, 73, 74, - 75, 76, 76, 77, 78, 79, 80, 81, - 82, 83, 84, 85, 86, 87, 88, 89, - 91, 93, 95, 96, 98, 100, 101, 102, - 104, 106, 108, 110, 112, 114, 116, 118, - 122, 124, 126, 128, 130, 132, 134, 136, - 138, 140, 143, 145, 148, 151, 154, 157 -}; - -static const uint16_t kAcTable[128] = { - 4, 5, 6, 7, 8, 9, 10, 11, - 12, 13, 14, 15, 16, 17, 18, 19, - 20, 21, 22, 23, 24, 25, 26, 27, - 28, 29, 30, 31, 32, 33, 34, 35, - 36, 37, 38, 39, 40, 41, 42, 43, - 44, 45, 46, 47, 48, 49, 50, 51, - 52, 53, 54, 55, 56, 57, 58, 60, - 62, 64, 66, 68, 70, 72, 74, 76, - 78, 80, 82, 84, 86, 88, 90, 92, - 94, 96, 98, 100, 102, 104, 106, 108, - 110, 112, 114, 116, 119, 122, 125, 128, - 131, 134, 137, 140, 143, 146, 149, 152, - 155, 158, 161, 164, 167, 170, 173, 177, - 181, 185, 189, 193, 197, 201, 205, 209, - 213, 217, 221, 225, 229, 234, 239, 245, - 249, 254, 259, 264, 269, 274, 279, 284 -}; - -static const uint16_t kAcTable2[128] = { - 8, 8, 9, 10, 12, 13, 15, 17, - 18, 20, 21, 23, 24, 26, 27, 29, - 31, 32, 34, 35, 37, 38, 40, 41, - 43, 44, 46, 48, 49, 51, 52, 54, - 55, 57, 58, 60, 62, 63, 65, 66, - 68, 69, 71, 72, 74, 75, 77, 79, - 80, 82, 83, 85, 86, 88, 89, 93, - 96, 99, 102, 105, 108, 111, 114, 117, - 120, 124, 127, 130, 133, 136, 139, 142, - 145, 148, 151, 155, 158, 161, 164, 167, - 170, 173, 176, 179, 184, 189, 193, 198, - 203, 207, 212, 217, 221, 226, 230, 235, - 240, 244, 249, 254, 258, 263, 268, 274, - 280, 286, 292, 299, 305, 311, 317, 323, - 330, 336, 342, 348, 354, 362, 370, 379, - 385, 393, 401, 409, 416, 424, 432, 440 -}; - -static const uint16_t kCoeffThresh[16] = { - 0, 10, 20, 30, - 10, 20, 30, 30, - 20, 30, 30, 30, - 30, 30, 30, 30 -}; - -// TODO(skal): tune more. Coeff thresholding? -static const uint8_t kBiasMatrices[3][16] = { // [3] = [luma-ac,luma-dc,chroma] - { 96, 96, 96, 96, - 96, 96, 96, 96, - 96, 96, 96, 96, - 96, 96, 96, 96 }, - { 96, 96, 96, 96, - 96, 96, 96, 96, - 96, 96, 96, 96, - 96, 96, 96, 96 }, - { 96, 96, 96, 96, - 96, 96, 96, 96, - 96, 96, 96, 96, - 96, 96, 96, 96 } -}; - -// Sharpening by (slightly) raising the hi-frequency coeffs (only for trellis). -// Hack-ish but helpful for mid-bitrate range. Use with care. -static const uint8_t kFreqSharpening[16] = { - 0, 30, 60, 90, - 30, 60, 90, 90, - 60, 90, 90, 90, - 90, 90, 90, 90 -}; - -//------------------------------------------------------------------------------ -// Initialize quantization parameters in VP8Matrix - -// Returns the average quantizer -static int ExpandMatrix(VP8Matrix* const m, int type) { - int i; - int sum = 0; - for (i = 2; i < 16; ++i) { - m->q_[i] = m->q_[1]; - } - for (i = 0; i < 16; ++i) { - const int j = kZigzag[i]; - const int bias = kBiasMatrices[type][j]; - m->iq_[j] = (1 << QFIX) / m->q_[j]; - m->bias_[j] = BIAS(bias); - // TODO(skal): tune kCoeffThresh[] - m->zthresh_[j] = ((256 /*+ kCoeffThresh[j]*/ - bias) * m->q_[j] + 127) >> 8; - m->sharpen_[j] = (kFreqSharpening[j] * m->q_[j]) >> 11; - sum += m->q_[j]; - } - return (sum + 8) >> 4; -} - -static void SetupMatrices(VP8Encoder* enc) { - int i; - const int tlambda_scale = - (enc->method_ >= 4) ? enc->config_->sns_strength - : 0; - const int num_segments = enc->segment_hdr_.num_segments_; - for (i = 0; i < num_segments; ++i) { - VP8SegmentInfo* const m = &enc->dqm_[i]; - const int q = m->quant_; - int q4, q16, quv; - m->y1_.q_[0] = kDcTable[clip(q + enc->dq_y1_dc_, 0, 127)]; - m->y1_.q_[1] = kAcTable[clip(q, 0, 127)]; - - m->y2_.q_[0] = kDcTable[ clip(q + enc->dq_y2_dc_, 0, 127)] * 2; - m->y2_.q_[1] = kAcTable2[clip(q + enc->dq_y2_ac_, 0, 127)]; - - m->uv_.q_[0] = kDcTable[clip(q + enc->dq_uv_dc_, 0, 117)]; - m->uv_.q_[1] = kAcTable[clip(q + enc->dq_uv_ac_, 0, 127)]; - - q4 = ExpandMatrix(&m->y1_, 0); - q16 = ExpandMatrix(&m->y2_, 1); - quv = ExpandMatrix(&m->uv_, 2); - - // TODO: Switch to kLambda*[] tables? - { - m->lambda_i4_ = (3 * q4 * q4) >> 7; - m->lambda_i16_ = (3 * q16 * q16); - m->lambda_uv_ = (3 * quv * quv) >> 6; - m->lambda_mode_ = (1 * q4 * q4) >> 7; - m->lambda_trellis_i4_ = (7 * q4 * q4) >> 3; - m->lambda_trellis_i16_ = (q16 * q16) >> 2; - m->lambda_trellis_uv_ = (quv *quv) << 1; - m->tlambda_ = (tlambda_scale * q4) >> 5; - } - } -} - -//------------------------------------------------------------------------------ -// Initialize filtering parameters - -// Very small filter-strength values have close to no visual effect. So we can -// save a little decoding-CPU by turning filtering off for these. -#define FSTRENGTH_CUTOFF 3 - -static void SetupFilterStrength(VP8Encoder* const enc) { - int i; - const int level0 = enc->config_->filter_strength; - for (i = 0; i < NUM_MB_SEGMENTS; ++i) { - // Segments with lower quantizer will be less filtered. TODO: tune (wrt SNS) - const int level = level0 * 256 * enc->dqm_[i].quant_ / 128; - const int f = level / (256 + enc->dqm_[i].beta_); - enc->dqm_[i].fstrength_ = (f < FSTRENGTH_CUTOFF) ? 0 : (f > 63) ? 63 : f; - } - // We record the initial strength (mainly for the case of 1-segment only). - enc->filter_hdr_.level_ = enc->dqm_[0].fstrength_; - enc->filter_hdr_.simple_ = (enc->config_->filter_type == 0); - enc->filter_hdr_.sharpness_ = enc->config_->filter_sharpness; -} - -//------------------------------------------------------------------------------ - -// Note: if you change the values below, remember that the max range -// allowed by the syntax for DQ_UV is [-16,16]. -#define MAX_DQ_UV (6) -#define MIN_DQ_UV (-4) - -// We want to emulate jpeg-like behaviour where the expected "good" quality -// is around q=75. Internally, our "good" middle is around c=50. So we -// map accordingly using linear piece-wise function -static double QualityToCompression(double q) { - const double c = q / 100.; - return (c < 0.75) ? c * (2. / 3.) : 2. * c - 1.; -} - -void VP8SetSegmentParams(VP8Encoder* const enc, float quality) { - int i; - int dq_uv_ac, dq_uv_dc; - const int num_segments = enc->config_->segments; - const double amp = SNS_TO_DQ * enc->config_->sns_strength / 100. / 128.; - const double c_base = QualityToCompression(quality); - for (i = 0; i < num_segments; ++i) { - // The file size roughly scales as pow(quantizer, 3.). Actually, the - // exponent is somewhere between 2.8 and 3.2, but we're mostly interested - // in the mid-quant range. So we scale the compressibility inversely to - // this power-law: quant ~= compression ^ 1/3. This law holds well for - // low quant. Finer modelling for high-quant would make use of kAcTable[] - // more explicitely. - // Additionally, we modulate the base exponent 1/3 to accommodate for the - // quantization susceptibility and allow denser segments to be quantized - // more. - const double expn = (1. - amp * enc->dqm_[i].alpha_) / 3.; - const double c = pow(c_base, expn); - const int q = (int)(127. * (1. - c)); - assert(expn > 0.); - enc->dqm_[i].quant_ = clip(q, 0, 127); - } - - // purely indicative in the bitstream (except for the 1-segment case) - enc->base_quant_ = enc->dqm_[0].quant_; - - // fill-in values for the unused segments (required by the syntax) - for (i = num_segments; i < NUM_MB_SEGMENTS; ++i) { - enc->dqm_[i].quant_ = enc->base_quant_; - } - - // uv_alpha_ is normally spread around ~60. The useful range is - // typically ~30 (quite bad) to ~100 (ok to decimate UV more). - // We map it to the safe maximal range of MAX/MIN_DQ_UV for dq_uv. - dq_uv_ac = (enc->uv_alpha_ - MID_ALPHA) * (MAX_DQ_UV - MIN_DQ_UV) - / (MAX_ALPHA - MIN_ALPHA); - // we rescale by the user-defined strength of adaptation - dq_uv_ac = dq_uv_ac * enc->config_->sns_strength / 100; - // and make it safe. - dq_uv_ac = clip(dq_uv_ac, MIN_DQ_UV, MAX_DQ_UV); - // We also boost the dc-uv-quant a little, based on sns-strength, since - // U/V channels are quite more reactive to high quants (flat DC-blocks - // tend to appear, and are displeasant). - dq_uv_dc = -4 * enc->config_->sns_strength / 100; - dq_uv_dc = clip(dq_uv_dc, -15, 15); // 4bit-signed max allowed - - enc->dq_y1_dc_ = 0; // TODO(skal): dq-lum - enc->dq_y2_dc_ = 0; - enc->dq_y2_ac_ = 0; - enc->dq_uv_dc_ = dq_uv_dc; - enc->dq_uv_ac_ = dq_uv_ac; - - SetupMatrices(enc); - - SetupFilterStrength(enc); // initialize segments' filtering, eventually -} - -//------------------------------------------------------------------------------ -// Form the predictions in cache - -// Must be ordered using {DC_PRED, TM_PRED, V_PRED, H_PRED} as index -const int VP8I16ModeOffsets[4] = { I16DC16, I16TM16, I16VE16, I16HE16 }; -const int VP8UVModeOffsets[4] = { C8DC8, C8TM8, C8VE8, C8HE8 }; - -// Must be indexed using {B_DC_PRED -> B_HU_PRED} as index -const int VP8I4ModeOffsets[NUM_BMODES] = { - I4DC4, I4TM4, I4VE4, I4HE4, I4RD4, I4VR4, I4LD4, I4VL4, I4HD4, I4HU4 -}; - -void VP8MakeLuma16Preds(const VP8EncIterator* const it) { - const VP8Encoder* const enc = it->enc_; - const uint8_t* const left = it->x_ ? enc->y_left_ : NULL; - const uint8_t* const top = it->y_ ? enc->y_top_ + it->x_ * 16 : NULL; - VP8EncPredLuma16(it->yuv_p_, left, top); -} - -void VP8MakeChroma8Preds(const VP8EncIterator* const it) { - const VP8Encoder* const enc = it->enc_; - const uint8_t* const left = it->x_ ? enc->u_left_ : NULL; - const uint8_t* const top = it->y_ ? enc->uv_top_ + it->x_ * 16 : NULL; - VP8EncPredChroma8(it->yuv_p_, left, top); -} - -void VP8MakeIntra4Preds(const VP8EncIterator* const it) { - VP8EncPredLuma4(it->yuv_p_, it->i4_top_); -} - -//------------------------------------------------------------------------------ -// Quantize - -// Layout: -// +----+ -// |YYYY| 0 -// |YYYY| 4 -// |YYYY| 8 -// |YYYY| 12 -// +----+ -// |UUVV| 16 -// |UUVV| 20 -// +----+ - -const int VP8Scan[16 + 4 + 4] = { - // Luma - 0 + 0 * BPS, 4 + 0 * BPS, 8 + 0 * BPS, 12 + 0 * BPS, - 0 + 4 * BPS, 4 + 4 * BPS, 8 + 4 * BPS, 12 + 4 * BPS, - 0 + 8 * BPS, 4 + 8 * BPS, 8 + 8 * BPS, 12 + 8 * BPS, - 0 + 12 * BPS, 4 + 12 * BPS, 8 + 12 * BPS, 12 + 12 * BPS, - - 0 + 0 * BPS, 4 + 0 * BPS, 0 + 4 * BPS, 4 + 4 * BPS, // U - 8 + 0 * BPS, 12 + 0 * BPS, 8 + 4 * BPS, 12 + 4 * BPS // V -}; - -//------------------------------------------------------------------------------ -// Distortion measurement - -static const uint16_t kWeightY[16] = { - 38, 32, 20, 9, 32, 28, 17, 7, 20, 17, 10, 4, 9, 7, 4, 2 -}; - -static const uint16_t kWeightTrellis[16] = { -#if USE_TDISTO == 0 - 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16 -#else - 30, 27, 19, 11, - 27, 24, 17, 10, - 19, 17, 12, 8, - 11, 10, 8, 6 -#endif -}; - -// Init/Copy the common fields in score. -static void InitScore(VP8ModeScore* const rd) { - rd->D = 0; - rd->SD = 0; - rd->R = 0; - rd->nz = 0; - rd->score = MAX_COST; -} - -static void CopyScore(VP8ModeScore* const dst, const VP8ModeScore* const src) { - dst->D = src->D; - dst->SD = src->SD; - dst->R = src->R; - dst->nz = src->nz; // note that nz is not accumulated, but just copied. - dst->score = src->score; -} - -static void AddScore(VP8ModeScore* const dst, const VP8ModeScore* const src) { - dst->D += src->D; - dst->SD += src->SD; - dst->R += src->R; - dst->nz |= src->nz; // here, new nz bits are accumulated. - dst->score += src->score; -} - -//------------------------------------------------------------------------------ -// Performs trellis-optimized quantization. - -// Trellis - -typedef struct { - int prev; // best previous - int level; // level - int sign; // sign of coeff_i - score_t cost; // bit cost - score_t error; // distortion = sum of (|coeff_i| - level_i * Q_i)^2 - int ctx; // context (only depends on 'level'. Could be spared.) -} Node; - -// If a coefficient was quantized to a value Q (using a neutral bias), -// we test all alternate possibilities between [Q-MIN_DELTA, Q+MAX_DELTA] -// We don't test negative values though. -#define MIN_DELTA 0 // how much lower level to try -#define MAX_DELTA 1 // how much higher -#define NUM_NODES (MIN_DELTA + 1 + MAX_DELTA) -#define NODE(n, l) (nodes[(n) + 1][(l) + MIN_DELTA]) - -static WEBP_INLINE void SetRDScore(int lambda, VP8ModeScore* const rd) { - // TODO: incorporate the "* 256" in the tables? - rd->score = rd->R * lambda + 256 * (rd->D + rd->SD); -} - -static WEBP_INLINE score_t RDScoreTrellis(int lambda, score_t rate, - score_t distortion) { - return rate * lambda + 256 * distortion; -} - -static int TrellisQuantizeBlock(const VP8EncIterator* const it, - int16_t in[16], int16_t out[16], - int ctx0, int coeff_type, - const VP8Matrix* const mtx, - int lambda) { - ProbaArray* const last_costs = it->enc_->proba_.coeffs_[coeff_type]; - CostArray* const costs = it->enc_->proba_.level_cost_[coeff_type]; - const int first = (coeff_type == 0) ? 1 : 0; - Node nodes[17][NUM_NODES]; - int best_path[3] = {-1, -1, -1}; // store best-last/best-level/best-previous - score_t best_score; - int best_node; - int last = first - 1; - int n, m, p, nz; - - { - score_t cost; - score_t max_error; - const int thresh = mtx->q_[1] * mtx->q_[1] / 4; - const int last_proba = last_costs[VP8EncBands[first]][ctx0][0]; - - // compute maximal distortion. - max_error = 0; - for (n = first; n < 16; ++n) { - const int j = kZigzag[n]; - const int err = in[j] * in[j]; - max_error += kWeightTrellis[j] * err; - if (err > thresh) last = n; - } - // we don't need to go inspect up to n = 16 coeffs. We can just go up - // to last + 1 (inclusive) without losing much. - if (last < 15) ++last; - - // compute 'skip' score. This is the max score one can do. - cost = VP8BitCost(0, last_proba); - best_score = RDScoreTrellis(lambda, cost, max_error); - - // initialize source node. - n = first - 1; - for (m = -MIN_DELTA; m <= MAX_DELTA; ++m) { - NODE(n, m).cost = 0; - NODE(n, m).error = max_error; - NODE(n, m).ctx = ctx0; - } - } - - // traverse trellis. - for (n = first; n <= last; ++n) { - const int j = kZigzag[n]; - const int Q = mtx->q_[j]; - const int iQ = mtx->iq_[j]; - const int B = BIAS(0x00); // neutral bias - // note: it's important to take sign of the _original_ coeff, - // so we don't have to consider level < 0 afterward. - const int sign = (in[j] < 0); - int coeff0 = (sign ? -in[j] : in[j]) + mtx->sharpen_[j]; - int level0; - if (coeff0 > 2047) coeff0 = 2047; - - level0 = QUANTDIV(coeff0, iQ, B); - // test all alternate level values around level0. - for (m = -MIN_DELTA; m <= MAX_DELTA; ++m) { - Node* const cur = &NODE(n, m); - int delta_error, new_error; - score_t cur_score = MAX_COST; - int level = level0 + m; - int last_proba; - - cur->sign = sign; - cur->level = level; - cur->ctx = (level == 0) ? 0 : (level == 1) ? 1 : 2; - if (level >= 2048 || level < 0) { // node is dead? - cur->cost = MAX_COST; - continue; - } - last_proba = last_costs[VP8EncBands[n + 1]][cur->ctx][0]; - - // Compute delta_error = how much coding this level will - // subtract as distortion to max_error - new_error = coeff0 - level * Q; - delta_error = - kWeightTrellis[j] * (coeff0 * coeff0 - new_error * new_error); - - // Inspect all possible non-dead predecessors. Retain only the best one. - for (p = -MIN_DELTA; p <= MAX_DELTA; ++p) { - const Node* const prev = &NODE(n - 1, p); - const int prev_ctx = prev->ctx; - const uint16_t* const tcost = costs[VP8EncBands[n]][prev_ctx]; - const score_t total_error = prev->error - delta_error; - score_t cost, base_cost, score; - - if (prev->cost >= MAX_COST) { // dead node? - continue; - } - - // Base cost of both terminal/non-terminal - base_cost = prev->cost + VP8LevelCost(tcost, level); - - // Examine node assuming it's a non-terminal one. - cost = base_cost; - if (level && n < 15) { - cost += VP8BitCost(1, last_proba); - } - score = RDScoreTrellis(lambda, cost, total_error); - if (score < cur_score) { - cur_score = score; - cur->cost = cost; - cur->error = total_error; - cur->prev = p; - } - - // Now, record best terminal node (and thus best entry in the graph). - if (level) { - cost = base_cost; - if (n < 15) cost += VP8BitCost(0, last_proba); - score = RDScoreTrellis(lambda, cost, total_error); - if (score < best_score) { - best_score = score; - best_path[0] = n; // best eob position - best_path[1] = m; // best level - best_path[2] = p; // best predecessor - } - } - } - } - } - - // Fresh start - memset(in + first, 0, (16 - first) * sizeof(*in)); - memset(out + first, 0, (16 - first) * sizeof(*out)); - if (best_path[0] == -1) { - return 0; // skip! - } - - // Unwind the best path. - // Note: best-prev on terminal node is not necessarily equal to the - // best_prev for non-terminal. So we patch best_path[2] in. - n = best_path[0]; - best_node = best_path[1]; - NODE(n, best_node).prev = best_path[2]; // force best-prev for terminal - nz = 0; - - for (; n >= first; --n) { - const Node* const node = &NODE(n, best_node); - const int j = kZigzag[n]; - out[n] = node->sign ? -node->level : node->level; - nz |= (node->level != 0); - in[j] = out[n] * mtx->q_[j]; - best_node = node->prev; - } - return nz; -} - -#undef NODE - -//------------------------------------------------------------------------------ -// Performs: difference, transform, quantize, back-transform, add -// all at once. Output is the reconstructed block in *yuv_out, and the -// quantized levels in *levels. - -static int ReconstructIntra16(VP8EncIterator* const it, - VP8ModeScore* const rd, - uint8_t* const yuv_out, - int mode) { - const VP8Encoder* const enc = it->enc_; - const uint8_t* const ref = it->yuv_p_ + VP8I16ModeOffsets[mode]; - const uint8_t* const src = it->yuv_in_ + Y_OFF; - const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_]; - int nz = 0; - int n; - int16_t tmp[16][16], dc_tmp[16]; - - for (n = 0; n < 16; ++n) { - VP8FTransform(src + VP8Scan[n], ref + VP8Scan[n], tmp[n]); - } - VP8FTransformWHT(tmp[0], dc_tmp); - nz |= VP8EncQuantizeBlock(dc_tmp, rd->y_dc_levels, 0, &dqm->y2_) << 24; - - if (DO_TRELLIS_I16 && it->do_trellis_) { - int x, y; - VP8IteratorNzToBytes(it); - for (y = 0, n = 0; y < 4; ++y) { - for (x = 0; x < 4; ++x, ++n) { - const int ctx = it->top_nz_[x] + it->left_nz_[y]; - const int non_zero = - TrellisQuantizeBlock(it, tmp[n], rd->y_ac_levels[n], ctx, 0, - &dqm->y1_, dqm->lambda_trellis_i16_); - it->top_nz_[x] = it->left_nz_[y] = non_zero; - nz |= non_zero << n; - } - } - } else { - for (n = 0; n < 16; ++n) { - nz |= VP8EncQuantizeBlock(tmp[n], rd->y_ac_levels[n], 1, &dqm->y1_) << n; - } - } - - // Transform back - VP8ITransformWHT(dc_tmp, tmp[0]); - for (n = 0; n < 16; n += 2) { - VP8ITransform(ref + VP8Scan[n], tmp[n], yuv_out + VP8Scan[n], 1); - } - - return nz; -} - -static int ReconstructIntra4(VP8EncIterator* const it, - int16_t levels[16], - const uint8_t* const src, - uint8_t* const yuv_out, - int mode) { - const VP8Encoder* const enc = it->enc_; - const uint8_t* const ref = it->yuv_p_ + VP8I4ModeOffsets[mode]; - const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_]; - int nz = 0; - int16_t tmp[16]; - - VP8FTransform(src, ref, tmp); - if (DO_TRELLIS_I4 && it->do_trellis_) { - const int x = it->i4_ & 3, y = it->i4_ >> 2; - const int ctx = it->top_nz_[x] + it->left_nz_[y]; - nz = TrellisQuantizeBlock(it, tmp, levels, ctx, 3, &dqm->y1_, - dqm->lambda_trellis_i4_); - } else { - nz = VP8EncQuantizeBlock(tmp, levels, 0, &dqm->y1_); - } - VP8ITransform(ref, tmp, yuv_out, 0); - return nz; -} - -static int ReconstructUV(VP8EncIterator* const it, VP8ModeScore* const rd, - uint8_t* const yuv_out, int mode) { - const VP8Encoder* const enc = it->enc_; - const uint8_t* const ref = it->yuv_p_ + VP8UVModeOffsets[mode]; - const uint8_t* const src = it->yuv_in_ + U_OFF; - const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_]; - int nz = 0; - int n; - int16_t tmp[8][16]; - - for (n = 0; n < 8; ++n) { - VP8FTransform(src + VP8Scan[16 + n], ref + VP8Scan[16 + n], tmp[n]); - } - if (DO_TRELLIS_UV && it->do_trellis_) { - int ch, x, y; - for (ch = 0, n = 0; ch <= 2; ch += 2) { - for (y = 0; y < 2; ++y) { - for (x = 0; x < 2; ++x, ++n) { - const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y]; - const int non_zero = - TrellisQuantizeBlock(it, tmp[n], rd->uv_levels[n], ctx, 2, - &dqm->uv_, dqm->lambda_trellis_uv_); - it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] = non_zero; - nz |= non_zero << n; - } - } - } - } else { - for (n = 0; n < 8; ++n) { - nz |= VP8EncQuantizeBlock(tmp[n], rd->uv_levels[n], 0, &dqm->uv_) << n; - } - } - - for (n = 0; n < 8; n += 2) { - VP8ITransform(ref + VP8Scan[16 + n], tmp[n], yuv_out + VP8Scan[16 + n], 1); - } - return (nz << 16); -} - -//------------------------------------------------------------------------------ -// RD-opt decision. Reconstruct each modes, evalue distortion and bit-cost. -// Pick the mode is lower RD-cost = Rate + lamba * Distortion. - -static void SwapPtr(uint8_t** a, uint8_t** b) { - uint8_t* const tmp = *a; - *a = *b; - *b = tmp; -} - -static void SwapOut(VP8EncIterator* const it) { - SwapPtr(&it->yuv_out_, &it->yuv_out2_); -} - -static void PickBestIntra16(VP8EncIterator* const it, VP8ModeScore* const rd) { - const VP8Encoder* const enc = it->enc_; - const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_]; - const int lambda = dqm->lambda_i16_; - const int tlambda = dqm->tlambda_; - const uint8_t* const src = it->yuv_in_ + Y_OFF; - VP8ModeScore rd16; - int mode; - - rd->mode_i16 = -1; - for (mode = 0; mode < 4; ++mode) { - uint8_t* const tmp_dst = it->yuv_out2_ + Y_OFF; // scratch buffer - int nz; - - // Reconstruct - nz = ReconstructIntra16(it, &rd16, tmp_dst, mode); - - // Measure RD-score - rd16.D = VP8SSE16x16(src, tmp_dst); - rd16.SD = tlambda ? MULT_8B(tlambda, VP8TDisto16x16(src, tmp_dst, kWeightY)) - : 0; - rd16.R = VP8GetCostLuma16(it, &rd16); - rd16.R += VP8FixedCostsI16[mode]; - - // Since we always examine Intra16 first, we can overwrite *rd directly. - SetRDScore(lambda, &rd16); - if (mode == 0 || rd16.score < rd->score) { - CopyScore(rd, &rd16); - rd->mode_i16 = mode; - rd->nz = nz; - memcpy(rd->y_ac_levels, rd16.y_ac_levels, sizeof(rd16.y_ac_levels)); - memcpy(rd->y_dc_levels, rd16.y_dc_levels, sizeof(rd16.y_dc_levels)); - SwapOut(it); - } - } - SetRDScore(dqm->lambda_mode_, rd); // finalize score for mode decision. - VP8SetIntra16Mode(it, rd->mode_i16); -} - -//------------------------------------------------------------------------------ - -// return the cost array corresponding to the surrounding prediction modes. -static const uint16_t* GetCostModeI4(VP8EncIterator* const it, - const uint8_t modes[16]) { - const int preds_w = it->enc_->preds_w_; - const int x = (it->i4_ & 3), y = it->i4_ >> 2; - const int left = (x == 0) ? it->preds_[y * preds_w - 1] : modes[it->i4_ - 1]; - const int top = (y == 0) ? it->preds_[-preds_w + x] : modes[it->i4_ - 4]; - return VP8FixedCostsI4[top][left]; -} - -static int PickBestIntra4(VP8EncIterator* const it, VP8ModeScore* const rd) { - const VP8Encoder* const enc = it->enc_; - const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_]; - const int lambda = dqm->lambda_i4_; - const int tlambda = dqm->tlambda_; - const uint8_t* const src0 = it->yuv_in_ + Y_OFF; - uint8_t* const best_blocks = it->yuv_out2_ + Y_OFF; - int total_header_bits = 0; - VP8ModeScore rd_best; - - if (enc->max_i4_header_bits_ == 0) { - return 0; - } - - InitScore(&rd_best); - rd_best.score = 211; // '211' is the value of VP8BitCost(0, 145) - VP8IteratorStartI4(it); - do { - VP8ModeScore rd_i4; - int mode; - int best_mode = -1; - const uint8_t* const src = src0 + VP8Scan[it->i4_]; - const uint16_t* const mode_costs = GetCostModeI4(it, rd->modes_i4); - uint8_t* best_block = best_blocks + VP8Scan[it->i4_]; - uint8_t* tmp_dst = it->yuv_p_ + I4TMP; // scratch buffer. - - InitScore(&rd_i4); - VP8MakeIntra4Preds(it); - for (mode = 0; mode < NUM_BMODES; ++mode) { - VP8ModeScore rd_tmp; - int16_t tmp_levels[16]; - - // Reconstruct - rd_tmp.nz = - ReconstructIntra4(it, tmp_levels, src, tmp_dst, mode) << it->i4_; - - // Compute RD-score - rd_tmp.D = VP8SSE4x4(src, tmp_dst); - rd_tmp.SD = - tlambda ? MULT_8B(tlambda, VP8TDisto4x4(src, tmp_dst, kWeightY)) - : 0; - rd_tmp.R = VP8GetCostLuma4(it, tmp_levels); - rd_tmp.R += mode_costs[mode]; - - SetRDScore(lambda, &rd_tmp); - if (best_mode < 0 || rd_tmp.score < rd_i4.score) { - CopyScore(&rd_i4, &rd_tmp); - best_mode = mode; - SwapPtr(&tmp_dst, &best_block); - memcpy(rd_best.y_ac_levels[it->i4_], tmp_levels, sizeof(tmp_levels)); - } - } - SetRDScore(dqm->lambda_mode_, &rd_i4); - AddScore(&rd_best, &rd_i4); - total_header_bits += mode_costs[best_mode]; - if (rd_best.score >= rd->score || - total_header_bits > enc->max_i4_header_bits_) { - return 0; - } - // Copy selected samples if not in the right place already. - if (best_block != best_blocks + VP8Scan[it->i4_]) - VP8Copy4x4(best_block, best_blocks + VP8Scan[it->i4_]); - rd->modes_i4[it->i4_] = best_mode; - it->top_nz_[it->i4_ & 3] = it->left_nz_[it->i4_ >> 2] = (rd_i4.nz ? 1 : 0); - } while (VP8IteratorRotateI4(it, best_blocks)); - - // finalize state - CopyScore(rd, &rd_best); - VP8SetIntra4Mode(it, rd->modes_i4); - SwapOut(it); - memcpy(rd->y_ac_levels, rd_best.y_ac_levels, sizeof(rd->y_ac_levels)); - return 1; // select intra4x4 over intra16x16 -} - -//------------------------------------------------------------------------------ - -static void PickBestUV(VP8EncIterator* const it, VP8ModeScore* const rd) { - const VP8Encoder* const enc = it->enc_; - const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_]; - const int lambda = dqm->lambda_uv_; - const uint8_t* const src = it->yuv_in_ + U_OFF; - uint8_t* const tmp_dst = it->yuv_out2_ + U_OFF; // scratch buffer - uint8_t* const dst0 = it->yuv_out_ + U_OFF; - VP8ModeScore rd_best; - int mode; - - rd->mode_uv = -1; - InitScore(&rd_best); - for (mode = 0; mode < 4; ++mode) { - VP8ModeScore rd_uv; - - // Reconstruct - rd_uv.nz = ReconstructUV(it, &rd_uv, tmp_dst, mode); - - // Compute RD-score - rd_uv.D = VP8SSE16x8(src, tmp_dst); - rd_uv.SD = 0; // TODO: should we call TDisto? it tends to flatten areas. - rd_uv.R = VP8GetCostUV(it, &rd_uv); - rd_uv.R += VP8FixedCostsUV[mode]; - - SetRDScore(lambda, &rd_uv); - if (mode == 0 || rd_uv.score < rd_best.score) { - CopyScore(&rd_best, &rd_uv); - rd->mode_uv = mode; - memcpy(rd->uv_levels, rd_uv.uv_levels, sizeof(rd->uv_levels)); - memcpy(dst0, tmp_dst, UV_SIZE); // TODO: SwapUVOut() ? - } - } - VP8SetIntraUVMode(it, rd->mode_uv); - AddScore(rd, &rd_best); -} - -//------------------------------------------------------------------------------ -// Final reconstruction and quantization. - -static void SimpleQuantize(VP8EncIterator* const it, VP8ModeScore* const rd) { - const VP8Encoder* const enc = it->enc_; - const int i16 = (it->mb_->type_ == 1); - int nz = 0; - - if (i16) { - nz = ReconstructIntra16(it, rd, it->yuv_out_ + Y_OFF, it->preds_[0]); - } else { - VP8IteratorStartI4(it); - do { - const int mode = - it->preds_[(it->i4_ & 3) + (it->i4_ >> 2) * enc->preds_w_]; - const uint8_t* const src = it->yuv_in_ + Y_OFF + VP8Scan[it->i4_]; - uint8_t* const dst = it->yuv_out_ + Y_OFF + VP8Scan[it->i4_]; - VP8MakeIntra4Preds(it); - nz |= ReconstructIntra4(it, rd->y_ac_levels[it->i4_], - src, dst, mode) << it->i4_; - } while (VP8IteratorRotateI4(it, it->yuv_out_ + Y_OFF)); - } - - nz |= ReconstructUV(it, rd, it->yuv_out_ + U_OFF, it->mb_->uv_mode_); - rd->nz = nz; -} - -//------------------------------------------------------------------------------ -// Entry point - -int VP8Decimate(VP8EncIterator* const it, VP8ModeScore* const rd, int rd_opt) { - int is_skipped; - - InitScore(rd); - - // We can perform predictions for Luma16x16 and Chroma8x8 already. - // Luma4x4 predictions needs to be done as-we-go. - VP8MakeLuma16Preds(it); - VP8MakeChroma8Preds(it); - - // for rd_opt = 2, we perform trellis-quant on the final decision only. - // for rd_opt > 2, we use it for every scoring (=much slower). - if (rd_opt > 0) { - it->do_trellis_ = (rd_opt > 2); - PickBestIntra16(it, rd); - if (it->enc_->method_ >= 2) { - PickBestIntra4(it, rd); - } - PickBestUV(it, rd); - if (rd_opt == 2) { - it->do_trellis_ = 1; - SimpleQuantize(it, rd); - } - } else { - // TODO: for method_ == 2, pick the best intra4/intra16 based on SSE - it->do_trellis_ = (it->enc_->method_ == 2); - SimpleQuantize(it, rd); - } - is_skipped = (rd->nz == 0); - VP8SetSkip(it, is_skipped); - return is_skipped; -} - -#if defined(__cplusplus) || defined(c_plusplus) -} // extern "C" -#endif |