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Merge "RTP: Pause echo suppressor when far-end volume is low." into gingerbread

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Chia-chi Yeh
2010-11-29 22:19:57 -08:00
committed by Android (Google) Code Review
parent 47ccfcb015 0c7d30660c
commit bd399b0bd2
1 changed files with 13 additions and 8 deletions
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21
voip/jni/rtp/EchoSuppressor.cpp
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@@ -160,22 +160,27 @@ void EchoSuppressor::run(int16_t *playbacked, int16_t *recorded)
}
// Compute correlations.
float corr2 = 0.0f;
int latency = 0;
float corr2 = 0.0f;
float varX = 0.0f;
float varY = mY2Sum - mWeight * mYSum * mYSum;
for (int i = mTailLength - 1; i >= 0; --i) {
float varX = mX2Sums[i] - mWeight * mXSums[i] * mXSums[i];
float cov = mXYSums[i] - mWeight * mXSums[i] * mYSum;
float c2 = cov * cov / (varX * varY + 1);
if (c2 > corr2) {
corr2 = c2;
latency = i;
if (cov > 0.0f) {
float varXi = mX2Sums[i] - mWeight * mXSums[i] * mXSums[i];
float corr2i = cov * cov / (varXi * varY + 1);
if (corr2i > corr2) {
varX = varXi;
corr2 = corr2i;
latency = i;
}
}
}
//LOGI("correlation^2 = %.10f, latency = %d", corr2, latency * mScale);
//LOGI("corr^2 %.5f, var %8.0f %8.0f, latency %d", corr2, varX, varY,
// latency * mScale);
// Do echo suppression.
if (corr2 > 0.1f) {
if (corr2 > 0.1f && varX > 10000.0f) {
int factor = (corr2 > 1.0f) ? 0 : (1.0f - sqrtf(corr2)) * 4096;
for (int i = 0; i < mSampleCount; ++i) {
recorded[i] = recorded[i] * factor >> 16;