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Merge "fast auto-determined filtering strength"

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This commit is contained in:
James Zern
2013-10-29 12:47:58 -07:00
committed by Gerrit Code Review
parent ac0bf951ca f8bfd5cd1e
commit d3408720d8
4 changed files with 122 additions and 26 deletions
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66
src/enc/quant.c
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@ -13,6 +13,7 @@
#include <assert.h>
#include <math.h>
#include <stdlib.h> // for abs()
#include "./vp8enci.h"
#include "./cost.h"
@ -181,17 +182,17 @@ static void SetupMatrices(VP8Encoder* enc) {
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;
}
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;
m->min_disto_ = 10 * m->y1_.q_[0]; // quantization-aware min disto
m->max_edge_ = 0;
}
}
@ -200,16 +201,21 @@ static void SetupMatrices(VP8Encoder* enc) {
// 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
#define FSTRENGTH_CUTOFF 2
static void SetupFilterStrength(VP8Encoder* const enc) {
int i;
const int level0 = enc->config_->filter_strength;
// level0 is in [0..500]. Using '-f 50' as filter_strength is mid-filtering.
const int level0 = 5 * 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;
VP8SegmentInfo* const m = &enc->dqm_[i];
// We focus on the quantization of AC coeffs.
const int qstep = kAcTable[clip(m->quant_, 0, 127)] >> 2;
const int base_strength =
VP8FilterStrengthFromDelta(enc->filter_hdr_.sharpness_, qstep);
// Segments with lower complexity ('beta') will be less filtered.
const int f = base_strength * level0 / (256 + m->beta_);
m->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_;
@ -648,10 +654,10 @@ static int ReconstructIntra16(VP8EncIterator* const it,
VP8ModeScore* const rd,
uint8_t* const yuv_out,
int mode) {
const VP8Encoder* const enc = it->enc_;
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_];
VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_];
int nz = 0;
int n;
int16_t tmp[16][16], dc_tmp[16];
@ -757,6 +763,17 @@ static int ReconstructUV(VP8EncIterator* const it, VP8ModeScore* const rd,
// RD-opt decision. Reconstruct each modes, evalue distortion and bit-cost.
// Pick the mode is lower RD-cost = Rate + lamba * Distortion.
static void StoreMaxDelta(VP8SegmentInfo* const dqm, const int16_t DCs[16]) {
// We look at the first three AC coefficients to determine what is the average
// delta between each sub-4x4 block.
const int v0 = abs(DCs[1]);
const int v1 = abs(DCs[4]);
const int v2 = abs(DCs[5]);
int max_v = (v0 > v1) ? v1 : v0;
max_v = (v2 > max_v) ? v2 : max_v;
if (max_v > dqm->max_edge_) dqm->max_edge_ = max_v;
}
static void SwapPtr(uint8_t** a, uint8_t** b) {
uint8_t* const tmp = *a;
*a = *b;
@ -768,8 +785,8 @@ static void SwapOut(VP8EncIterator* const it) {
}
static void PickBestIntra16(VP8EncIterator* const it, VP8ModeScore* const rd) {
const VP8Encoder* const enc = it->enc_;
const VP8SegmentInfo* const dqm = &enc->dqm_[it->mb_->segment_];
VP8Encoder* const enc = it->enc_;
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;
@ -804,6 +821,13 @@ static void PickBestIntra16(VP8EncIterator* const it, VP8ModeScore* const rd) {
}
SetRDScore(dqm->lambda_mode_, rd); // finalize score for mode decision.
VP8SetIntra16Mode(it, rd->mode_i16);
// we have a blocky macroblock (only DCs are non-zero) with fairly high
// distortion, record max delta so we can later adjust the minimal filtering
// strength needed to smooth these blocks out.
if ((rd->nz & 0xffff) == 0 && rd->D > dqm->min_disto_) {
StoreMaxDelta(dqm, rd->y_dc_levels);
}
}
//------------------------------------------------------------------------------