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small clean-up in ExpandMatrix()

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Change-Id: Ib06cb1658a6548f06bb7320310b3864881b606a7
This commit is contained in:
Pascal Massimino 2013-10-25 13:28:12 +00:00 committed by James Zern
parent 43148b6cd2
commit ac0bf951ca
1 changed files with 7 additions and 8 deletions
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15
src/enc/quant.c
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@ -127,7 +127,7 @@ static const uint8_t kBiasMatrices[3][16] = { // [3] = [luma-ac,luma-dc,chroma]
96, 96, 96, 96 }
};
// Sharpening by (slightly) raising the hi-frequency coeffs (only for trellis).
// Sharpening by (slightly) raising the hi-frequency coeffs.
// Hack-ish but helpful for mid-bitrate range. Use with care.
static const uint8_t kFreqSharpening[16] = {
0, 30, 60, 90,
@ -147,14 +147,13 @@ static int ExpandMatrix(VP8Matrix* const m, int type) {
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);
const int bias = kBiasMatrices[type][i];
m->iq_[i] = (1 << QFIX) / m->q_[i];
m->bias_[i] = 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];
m->zthresh_[i] = ((256 /*+ kCoeffThresh[i]*/ - bias) * m->q_[i] + 127) >> 8;
m->sharpen_[i] = (kFreqSharpening[i] * m->q_[i]) >> 11;
sum += m->q_[i];
}
return (sum + 8) >> 4;
}