Merge "Fix for compressor kneewidth computation" into pi-dev (dddee581) · Commits · e / os / android_frameworks_av

media/libeffects/dynamicsproc/dsp/DPFrequency.cpp

+39 −37

Original line number	Diff line number	Diff line
		@@ -533,41 +533,45 @@ size_t DPFrequency::processFirstStages(ChannelBuffer &cb) {
		fTheta = exp(-1.0 / (fFRelSec * mBlocksPerSecond));
		}


		float fEnv = (1.0 - fTheta) * fEnergySum + fTheta * pMbcBandParams->previousEnvelope;
		//preserve for next iteration
		pMbcBandParams->previousEnvelope = fEnv;

		float fThreshold = dBtoLinear(pMbcBandParams->thresholdDb);
		float fNoiseGateThreshold = dBtoLinear(pMbcBandParams->noiseGateThresholdDb);

		float fNewFactor = 1.0;

		if (fEnv > fThreshold) {
		float fDbAbove = linearToDb(fThreshold / fEnv);
		float fDbTarget = fDbAbove / pMbcBandParams->ratio;
		float fDbChange = fDbAbove - fDbTarget;
		fNewFactor = dBtoLinear(fDbChange);
		} else if (fEnv < fNoiseGateThreshold) {
		if (fEnv < MIN_ENVELOPE) {
		fEnv = MIN_ENVELOPE;
		}
		float fDbBelow = linearToDb(fNoiseGateThreshold / fEnv);
		float fDbTarget = fDbBelow / pMbcBandParams->expanderRatio;
		float fDbChange = fDbBelow - fDbTarget;
		fNewFactor = dBtoLinear(fDbChange);
		}
		const float envDb = linearToDb(fEnv);
		float newLevelDb = envDb;
		//using shorter variables for code clarity
		const float thresholdDb = pMbcBandParams->thresholdDb;
		const float ratio = pMbcBandParams->ratio;
		const float kneeWidthDbHalf = pMbcBandParams->kneeWidthDb / 2;
		const float noiseGateThresholdDb = pMbcBandParams->noiseGateThresholdDb;
		const float expanderRatio = pMbcBandParams->expanderRatio;

		//find segment
		if (envDb > thresholdDb + kneeWidthDbHalf) {
		//compression segment
		newLevelDb = envDb + ((1 / ratio) - 1) * (envDb - thresholdDb);
		} else if (envDb > thresholdDb - kneeWidthDbHalf) {
		//knee-compression segment
		float temp = (envDb - thresholdDb + kneeWidthDbHalf);
		newLevelDb = envDb + ((1 / ratio) - 1) *
		temp * temp / (kneeWidthDbHalf * 4);
		} else if (envDb < noiseGateThresholdDb) {
		//expander segment
		newLevelDb = noiseGateThresholdDb -
		expanderRatio * (noiseGateThresholdDb - envDb);
		}

		float newFactor = dBtoLinear(newLevelDb - envDb);

		//apply post gain.
		fNewFactor *= dBtoLinear(pMbcBandParams->gainPostDb);

		if (fNewFactor < 0) {
		fNewFactor = 0;
		}
		newFactor *= dBtoLinear(pMbcBandParams->gainPostDb);

		//apply to this band
		for (size_t k = pMbcBandParams->binStart; k <= pMbcBandParams->binStop; k++) {
		cb.complexTemp[k] *= fNewFactor;
		cb.complexTemp[k] *= newFactor;
		}

		} //end per band process
		@@ -604,22 +608,20 @@ size_t DPFrequency::processFirstStages(ChannelBuffer &cb) {
		//preserve for next iteration
		cb.mLimiterParams.previousEnvelope = fEnv;

		float fThreshold = dBtoLinear(cb.mLimiterParams.thresholdDb);
		const float envDb = linearToDb(fEnv);
		float newFactorDb = 0;
		//using shorter variables for code clarity
		const float thresholdDb = cb.mLimiterParams.thresholdDb;
		const float ratio = cb.mLimiterParams.ratio;

		float fNewFactor = 1.0;

		if (fEnv > fThreshold) {
		float fDbAbove = linearToDb(fThreshold / fEnv);
		float fDbTarget = fDbAbove / cb.mLimiterParams.ratio;
		float fDbChange = fDbAbove - fDbTarget;
		fNewFactor = dBtoLinear(fDbChange);
		if (envDb > thresholdDb) {
		//limiter segment
		newFactorDb = ((1 / ratio) - 1) * (envDb - thresholdDb);
		}

		if (fNewFactor < 0) {
		fNewFactor = 0;
		}
		float newFactor = dBtoLinear(newFactorDb);

		cb.mLimiterParams.newFactor = fNewFactor;
		cb.mLimiterParams.newFactor = newFactor;

		} //end Limiter
		return mBlockSize;