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lossy encoding: ~3% speed-up

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incorporate non-last cost in per-level cost table

also: correct trellis-quant cost evaluation at nodes
(output a little bit different now). Method 6 is ~4% faster.

Change-Id: Ic48bd6d33f9193838216e7dc3a9f9c5508a1fbe8
This commit is contained in:
Pascal Massimino
2014-02-26 05:52:24 -08:00
parent e8605e9625
commit 390c8b316d
3 changed files with 20 additions and 22 deletions
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24
src/enc/quant.c
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@ -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