Merge "Reduce loudness compensation latency and noise" into gingerbread (2122f6e8) · Commits · e / os / android_frameworks_base

media/libeffects/cyanogen-dsp/EffectEqualizer.cpp

+35 −29

Original line number	Diff line number	Diff line
		@@ -61,7 +61,7 @@ static int64_t toFixedPoint(float in) {
		}

		EffectEqualizer::EffectEqualizer()
		: mLoudnessAdjustment(10000.f), mLoudness(50.f)
		: mLoudnessAdjustment(10000.f), mLoudness(50.f), mNextUpdate(0), mNextUpdateInterval(1000), mPowerSquared(0)
		{
		for (int32_t i = 0; i < 5; i ++) {
		mBand[i] = 0;
		@@ -79,9 +79,10 @@ int32_t EffectEqualizer::command(uint32_t cmdCode, uint32_t cmdSize, void* pCmdD
		return 0;
		}

		/* Weigher for estimating bass compensation. Our adjustments have range from 62.5 to 4000 Hz.
		* Most of the adjustment is at the 62.5 Hz band, so we must concentrate on bass region. */
		mWeigher.setLowPass(1000.0, mSamplingRate, sqrtf(2)/2.);
		/* Weigher for estimating bass compensation. */
		mWeigher.setBandPass(2200.0, mSamplingRate, 0.33);
		/* 100 updates per second. */
		mNextUpdateInterval = int32_t(mSamplingRate / 100.);

		int32_t replyData = (int32_t ) pReplyData;
		*replyData = 0;
		@@ -195,10 +196,12 @@ int32_t EffectEqualizer::command(uint32_t cmdCode, uint32_t cmdSize, void* pCmdD
		* sound pressure level.
		*
		* The boost can be calculated as linear scaling of the following adjustment:
		* 62.5 Hz +24 dB
		* 250 Hz +10 dB
		* 20 Hz +40 dB (unmodeled)
		* 62.5 Hz +20 dB
		* 250 Hz +8 dB
		* 1000 Hz 0 dB
		* 4000 Hz -6 dB
		* 4000 Hz -3 dB
		* 16000 Hz +6 dB
		*
		* The boost will be applied maximally for signals of 20 dB and less,
		* and linearly decreased for signals 20 dB ... 100 dB, and no adjustment is
		@@ -206,7 +209,7 @@ int32_t EffectEqualizer::command(uint32_t cmdCode, uint32_t cmdSize, void* pCmdD
		* digital sound level against the audio.
		*/
		float EffectEqualizer::getAdjustedBand(int32_t band) {
		const float adj[5] = { 24.0, 10.0, 0.0, -6.0, 0.0 };
		const float adj[5] = { 20.0, 8.0, 0.0, -3.0, 6.0 };

		float loudnessLevel = mLoudness + mLoudnessAdjustment;
		if (loudnessLevel > 100.f) {
		@@ -236,16 +239,35 @@ void EffectEqualizer::refreshBands()

		int32_t EffectEqualizer::process_effect(audio_buffer_t in, audio_buffer_t out)
		{
		for (uint32_t i = 0; i < in->frameCount; i ++) {
		if (mNextUpdate == 0) {
		float signalPowerDb = logf(mPowerSquared / mNextUpdateInterval / float(int64_t(1) << 48) + 1e-10f) / logf(10.0f) * 10.0f;
		signalPowerDb += 96.0f + 10.0f;

		/* Limit automatic EQ to sub-dB adjustments to limit the noise
		* introduced by updates. */
		if (mLoudness < signalPowerDb - .5) {
		mLoudness += .5;
		} else if (mLoudness > signalPowerDb + .5) {
		mLoudness -= .5;
		} else {
		mLoudness = signalPowerDb;
		}

		/* Update EQ. */
		refreshBands();

		int64_t maximumPowerSquared = 0;
		for (uint32_t i = 0; i < in->frameCount; i ++) {
		mNextUpdate = mNextUpdateInterval;
		mPowerSquared = 0;
		}
		mNextUpdate --;

		int32_t tmpL = read(in, i * 2);
		int32_t tmpR = read(in, i * 2 + 1);

		/* Calculate signal loudness estimate */
		int64_t weight = mWeigher.process(tmpL + tmpR);
		maximumPowerSquared += weight * weight;
		mPowerSquared += weight * weight;

		/* first "shelve" is just gain */
		tmpL = tmpL * mGain >> 32;
		@@ -260,22 +282,6 @@ int32_t EffectEqualizer::process_effect(audio_buffer_t in, audio_buffer_t out)
		write(out, i * 2, tmpL);
		write(out, i * 2 + 1, tmpR);
		}
		maximumPowerSquared /= in->frameCount;

		float signalPowerDb = logf(maximumPowerSquared / float(int64_t(1) << 48) + 1e-10f) / logf(10.0f) * 10.0f;
		signalPowerDb += 96.0f;

		/* Limit automatic EQ to maximum of 10 dB adjustment rate per second.
		* a frame-to-frame adjusted should not be very large because adjustments do cause
		* small glitches at the output. These may be audible if single step is too large. */
		float maxAdj = in->frameCount / mSamplingRate * 10.f;
		if (mLoudness < signalPowerDb - maxAdj) {
		mLoudness += maxAdj;
		} else if (mLoudness > signalPowerDb + maxAdj) {
		mLoudness -= maxAdj;
		} else {
		mLoudness = signalPowerDb;
		}

		return 0;
		}

media/libeffects/cyanogen-dsp/EffectEqualizer.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -20,6 +20,9 @@ class EffectEqualizer : public Effect {

		Biquad mWeigher;
		float mLoudness;
		int32_t mNextUpdate;
		int32_t mNextUpdateInterval;
		int64_t mPowerSquared;

		void setBand(int32_t idx, float dB);
		float getAdjustedBand(int32_t idx);