dany/libwebp
1
0
Fork 0
mirror of https://github.com/webmproject/libwebp.git synced 2024-12-27 22:28:22 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity

Merge "lossy encoding: ~3% speed-up"

Browse Source
This commit is contained in:
Pascal Massimino 2014-02-27 11:42:16 -08:00 committed by Gerrit Code Review
commit b66f2227c1
3 changed files with 20 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
src/enc/cost.c
View File

@ -360,9 +360,10 @@ void VP8CalculateLevelCosts(VP8Proba* const proba) {
for (ctx = 0; ctx < NUM_CTX; ++ctx) {
const uint8_t* const p = proba->coeffs_[ctype][band][ctx];
uint16_t* const table = proba->level_cost_[ctype][band][ctx];
const int cost_base = VP8BitCost(1, p[1]);
const int cost0 = (ctx > 0) ? VP8BitCost(1, p[0]) : 0;
const int cost_base = VP8BitCost(1, p[1]) + cost0;
int v;
table[0] = VP8BitCost(0, p[1]);
table[0] = VP8BitCost(0, p[1]) + cost0;
for (v = 1; v <= MAX_VARIABLE_LEVEL; ++v) {
table[v] = cost_base + VariableLevelCost(v, p);
}

13
src/enc/frame.c
View File

@ -199,8 +199,9 @@ static int RecordCoeffs(int ctx, const VP8Residual* const res) {
Record((v >= 3 + (8 << 3)), s + 10);
}
#else
if (v > MAX_VARIABLE_LEVEL)
if (v > MAX_VARIABLE_LEVEL) {
v = MAX_VARIABLE_LEVEL;
}
{
const int bits = VP8LevelCodes[v - 1][1];
@ -339,22 +340,22 @@ static void SetResidualCoeffs(const int16_t* const coeffs,
static int GetResidualCost(int ctx0, const VP8Residual* const res) {
int n = res->first;
// should be prob[VP8EncBands[n]], but it's equivalent for n=0 or 1
int p0 = res->prob[n][ctx0][0];
const int p0 = res->prob[n][ctx0][0];
const uint16_t* t = res->cost[n][ctx0];
int cost;
// bit_cost(1, p0) is already incorporated in t[] tables, but only if ctx != 0
// (as required by the syntax). For ctx0 == 0, we need to add it here or it'll
// be missing during the loop.
int cost = (ctx0 == 0) ? VP8BitCost(1, p0) : 0;
if (res->last < 0) {
return VP8BitCost(0, p0);
}
cost = VP8BitCost(1, p0);
for (; n < res->last; ++n) {
const int v = abs(res->coeffs[n]);
const int b = VP8EncBands[n + 1];
const int ctx = (v >= 2) ? 2 : v;
cost += VP8LevelCost(t, v);
t = res->cost[b][ctx];
// the masking trick is faster than "if (v) cost += ..." with clang
cost += (v ? ~0U : 0) & VP8BitCost(1, res->prob[b][ctx][0]);
}
// Last coefficient is always non-zero
{

24
src/enc/quant.c
View File

@ -548,7 +548,7 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
int ctx0, int coeff_type,
const VP8Matrix* const mtx,
int lambda) {
ProbaArray* const last_costs = it->enc_->proba_.coeffs_[coeff_type];
ProbaArray* const probas = 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];
@ -562,7 +562,7 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
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];
const int last_proba = probas[VP8EncBands[first]][ctx0][0];
// compute maximal distortion.
max_error = 0;
@ -583,7 +583,7 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
// initialize source node.
n = first - 1;
for (m = -MIN_DELTA; m <= MAX_DELTA; ++m) {
NODE(n, m).cost = 0;
NODE(n, m).cost = (ctx0 == 0) ? VP8BitCost(1, last_proba) : 0;
NODE(n, m).error = max_error;
NODE(n, m).ctx = ctx0;
}
@ -608,7 +608,7 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
int delta_error, new_error;
score_t cur_score = MAX_COST;
int level = level0 + m;
int last_proba;
int last_pos_cost; // extra cost if last coeff's position is < 15
cur->sign = sign;
cur->level = level;
@ -617,7 +617,9 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
cur->cost = MAX_COST;
continue;
}
last_proba = last_costs[VP8EncBands[n + 1]][cur->ctx][0];
last_pos_cost =
(n < 15) ? VP8BitCost(0, probas[VP8EncBands[n + 1]][cur->ctx][0])
: 0;
// Compute delta_error = how much coding this level will
// subtract as distortion to max_error
@ -631,20 +633,16 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
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;
score_t cost, score;
if (prev->cost >= MAX_COST) { // dead node?
continue;
}
// Base cost of both terminal/non-terminal
base_cost = prev->cost + VP8LevelCost(tcost, level);
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;
@ -655,9 +653,7 @@ static int TrellisQuantizeBlock(const VP8EncIterator* const it,
// 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);
score = RDScoreTrellis(lambda, cost + last_pos_cost, total_error);
if (score < best_score) {
best_score = score;
best_path[0] = n; // best eob position