Merge "Do headset filter in center+side audio space" into gingerbread (80e48648) · Commits · e / os / android_frameworks_base

media/libeffects/cyanogen-dsp/Android.mk

+1 −0

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@ LOCAL_SRC_FILES := \
		EffectCompression.cpp \
		EffectEqualizer.cpp \
		EffectVirtualizer.cpp \
		FIR16.cpp \
		# terminator

		LOCAL_C_INCLUDES += \

media/libeffects/cyanogen-dsp/EffectVirtualizer.cpp

+39 −27

Original line number	Diff line number	Diff line
		@@ -38,6 +38,27 @@ EffectVirtualizer::EffectVirtualizer()
		int32_t EffectVirtualizer::command(uint32_t cmdCode, uint32_t cmdSize, void* pCmdData, uint32_t* replySize, void* pReplyData)
		{
		if (cmdCode == EFFECT_CMD_CONFIGURE) {
		/* Preliminary design -- needs more work.
		* NOT ACTUALLY USED. */
		float fir44100[16] = {
		0.584375000000000,
		0.080172281918782,
		0.049463834764832,
		-0.015690873571518,
		-0.065625000000000,
		-0.045552813136128,
		0.031786165235168,
		0.106071404788864,
		0.134375000000000,
		0.106071404788864,
		0.031786165235168,
		-0.045552813136128,
		-0.065625000000000,
		-0.015690873571518,
		0.049463834764832,
		0.080172281918782
		};

		int32_t ret = Effect::configure(pCmdData);
		if (ret != 0) {
		int32_t replyData = (int32_t ) pReplyData;
		@@ -45,13 +66,13 @@ int32_t EffectVirtualizer::command(uint32_t cmdCode, uint32_t cmdSize, void* pCm
		return 0;
		}

		mReverbDelayL.setParameters(mSamplingRate, 0.030f);
		mReverbDelayR.setParameters(mSamplingRate, 0.030f);
		/* Haas effect delay */
		mReverbDelayL.setParameters(mSamplingRate, 0.025f);
		mReverbDelayR.setParameters(mSamplingRate, 0.025f);
		/* Center channel forward direction adjustment filter. */
		mColorization.setParameters(fir44100);
		/* the -3 dB point is around 650 Hz, giving about 300 us to work with */
		mLocalizationL.setHighShelf(800.0f, mSamplingRate, -11.0f, 0.72f);
		mLocalizationR.setHighShelf(800.0f, mSamplingRate, -11.0f, 0.72f);
		/* Rockbox has a 0.3 ms delay line (13 samples at 44100 Hz), but
		* I think it makes the whole effect sound pretty bad so I skipped it! */
		mLocalization.setHighShelf(800.0f, mSamplingRate, -11.0f, 0.72f);

		mDelayDataL = 0;
		mDelayDataR = 0;
		@@ -152,28 +173,19 @@ int32_t EffectVirtualizer::process(audio_buffer_t* in, audio_buffer_t* out)
		dataL += dryL;
		dataR += dryR;

		/* In matrix decoding, center channel is mixed at 0.7 and the main channel at 1.
		* It follows that the sum of them is 1.7, and the proportion of the main channel
		* must be 1 / 1.7, or about 6/10. Assuming it is so, 4/10 is the contribution
		* of center, and when 2 channels are combined, the scaler is 2/10 or 1/5.
		*
		* We could try to dynamically adjust this divisor based on cross-correlation
		* between left/right channels, which would allow us to recover a reasonable
		* estimate of the music's original center channel. */
		int32_t center = (dataL + dataR) / 5;
		int32_t directL = (dataL - center);
		int32_t directR = (dataR - center);

		/* We assume center channel reaches both ears with no coloration required.
		* We could also handle it differently at reverb stage... */

		/* Apply localization filter. */
		int32_t localizedL = mLocalizationL.process(directL);
		int32_t localizedR = mLocalizationR.process(directR);

		/* Mix difference between channels. dataX = directX + center. */
		write(out, i * 2, dataL + localizedR);
		write(out, i * 2 + 1, dataR + localizedL);
		/* Center channel. */
		int32_t center = (dataL + dataR) >> 1;
		/* Direct radiation components. */
		int32_t side = (dataL - dataR) >> 1;

		/* Adjust derived center channel coloration to emphasize forward
		* direction impression. (XXX: disabled until configurable). */
		//center = mColorization.process(center);
		/* Sound reaching ear from the opposite speaker */
		side -= mLocalization.process(side);

		write(out, i * 2, center + side);
		write(out, i * 2 + 1, center - side);
		}

		return mEnable ? 0 : -ENODATA;

media/libeffects/cyanogen-dsp/EffectVirtualizer.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@
		#include "Biquad.h"
		#include "Delay.h"
		#include "Effect.h"
		#include "FIR16.h"

		class EffectVirtualizer : public Effect {
		private:
		@@ -15,7 +16,8 @@ class EffectVirtualizer : public Effect {

		Delay mReverbDelayL, mReverbDelayR;
		int64_t mDelayDataL, mDelayDataR;
		Biquad mLocalizationL, mLocalizationR;
		FIR16 mColorization;
		Biquad mLocalization;

		void refreshStrength();

media/libeffects/cyanogen-dsp/FIR16.cpp

0 → 100644

+50 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2011 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		#include "FIR16.h"

		#include <string.h>

		FIR16::FIR16()
		: mIndex(0)
		{
		memset(mState, 0, sizeof(mState));
		memset(mCoeff, 0, sizeof(mCoeff));
		}

		FIR16::~FIR16()
		{
		}

		void FIR16::setParameters(float coeff[16])
		{
		for (int32_t i = 0; i < 16; i ++) {
		mCoeff[i] = int64_t(coeff[i] * (int64_t(1) << 32));
		}
		}

		int32_t FIR16::process(int32_t x0)
		{
		mIndex --;
		mState[mIndex & 0xf] = x0;

		int64_t y = 0;
		for (int32_t i = 0; i < 16; i ++) {
		y += mCoeff[i] * mState[(i + mIndex) & 0xf];
		}

		return int32_t(y >> 32);
		}

media/libeffects/cyanogen-dsp/FIR16.h

0 → 100644

+15 −0

Original line number	Diff line number	Diff line
		#pragma once

		#include <stdint.h>

		class FIR16 {
		int64_t mCoeff[16];
		int32_t mState[16];
		int32_t mIndex;

		public:
		FIR16();
		~FIR16();
		void setParameters(float coeff[16]);
		int32_t process(int32_t x0);
		};