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

    }

    // 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;

        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;