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fix filtering auto-adjustment

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the min-distortion was quite too low. And we were also
considering the fully skipped macroblocks (nz=0) in the stats.
We need to have at least *some* non-zero dc coeffs (nz=0x100XXXX).

Fix also two typos in StoreMaxDelta: the v0/v1 comparison was wrong,
and the DCs[] coeffs are actually already in ZigZag order.

Change-Id: I602aaa74b36f7ce80017e506212c7d6fd9deba1f
(cherry picked from commit e4cd4daf74)
This commit is contained in:
Pascal Massimino 2016-11-07 04:41:45 -08:00 committed by James Zern
parent ed9dec41a5
commit e168af8c6c
1 changed files with 5 additions and 5 deletions
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10
src/enc/quant.c
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@ -278,7 +278,7 @@ static void SetupMatrices(VP8Encoder* enc) {
CheckLambdaValue(&m->lambda_trellis_uv_);
CheckLambdaValue(&m->tlambda_);
m->min_disto_ = 10 * m->y1_.q_[0]; // quantization-aware min disto
m->min_disto_ = 20 * m->y1_.q_[0]; // quantization-aware min disto
m->max_edge_ = 0;
m->i4_penalty_ = 1000 * q_i4 * q_i4;
@ -874,9 +874,9 @@ 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;
const int v1 = abs(DCs[2]);
const int v2 = abs(DCs[4]);
int max_v = (v1 > v0) ? v1 : v0;
max_v = (v2 > max_v) ? v2 : max_v;
if (max_v > dqm->max_edge_) dqm->max_edge_ = max_v;
}
@ -957,7 +957,7 @@ static void PickBestIntra16(VP8EncIterator* const it, VP8ModeScore* rd) {
// 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_) {
if ((rd->nz & 0x100ffff) == 0x1000000 && rd->D > dqm->min_disto_) {
StoreMaxDelta(dqm, rd->y_dc_levels);
}
}