AudioResamplerSinc.h revision c19e22450e6e3d07594c935c7a9522e85e909e82
165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian/* 265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * Copyright (C) 2007 The Android Open Source Project 365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * 465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * Licensed under the Apache License, Version 2.0 (the "License"); 565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * you may not use this file except in compliance with the License. 665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * You may obtain a copy of the License at 765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * 865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * http://www.apache.org/licenses/LICENSE-2.0 965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * 1065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * Unless required by applicable law or agreed to in writing, software 1165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * distributed under the License is distributed on an "AS IS" BASIS, 1265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * See the License for the specific language governing permissions and 1465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian * limitations under the License. 1565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian */ 1665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 1765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#ifndef ANDROID_AUDIO_RESAMPLER_SINC_H 1865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#define ANDROID_AUDIO_RESAMPLER_SINC_H 1965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 2065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#include <stdint.h> 2165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#include <sys/types.h> 2265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#include <cutils/log.h> 2365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 2465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#include "AudioResampler.h" 2565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 2665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopiannamespace android { 2765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 2865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian// ---------------------------------------------------------------------------- 2965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 3065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopianclass AudioResamplerSinc : public AudioResampler { 3165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopianpublic: 3265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian AudioResamplerSinc(int bitDepth, int inChannelCount, int32_t sampleRate); 3365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 34c19e22450e6e3d07594c935c7a9522e85e909e82Glenn Kasten virtual ~AudioResamplerSinc(); 3565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 3665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian virtual void resample(int32_t* out, size_t outFrameCount, 3765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian AudioBufferProvider* provider); 3865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopianprivate: 3965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian void init(); 4065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 4165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian template<int CHANNELS> 4265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian void resample(int32_t* out, size_t outFrameCount, 4365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian AudioBufferProvider* provider); 4465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 4565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian template<int CHANNELS> 4665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian inline void filterCoefficient( 4754c3b66444ebfb9f2265ee70ac3b76ccefa0506aGlenn Kasten int32_t& l, int32_t& r, uint32_t phase, const int16_t *samples); 4865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 4965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian template<int CHANNELS> 5065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian inline void interpolate( 5165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian int32_t& l, int32_t& r, 5254c3b66444ebfb9f2265ee70ac3b76ccefa0506aGlenn Kasten const int32_t* coefs, int16_t lerp, const int16_t* samples); 5365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 5465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian template<int CHANNELS> 5565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian inline void read(int16_t*& impulse, uint32_t& phaseFraction, 5654c3b66444ebfb9f2265ee70ac3b76ccefa0506aGlenn Kasten const int16_t* in, size_t inputIndex); 5765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 5865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian int16_t *mState; 5965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian int16_t *mImpulse; 6065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian int16_t *mRingFull; 6165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 6254c3b66444ebfb9f2265ee70ac3b76ccefa0506aGlenn Kasten const int32_t * mFirCoefs; 6365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int32_t mFirCoefsDown[]; 6465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int32_t mFirCoefsUp[]; 6565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 6665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian // ---------------------------------------------------------------------------- 6765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int32_t RESAMPLE_FIR_NUM_COEF = 8; 6865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int32_t RESAMPLE_FIR_LERP_INT_BITS = 4; 6965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 7065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian // we have 16 coefs samples per zero-crossing 7165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int coefsBits = RESAMPLE_FIR_LERP_INT_BITS; // 4 7265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int cShift = kNumPhaseBits - coefsBits; // 26 7365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const uint32_t cMask = ((1<<coefsBits)-1) << cShift; // 0xf<<26 = 3c00 0000 7465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 7565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian // and we use 15 bits to interpolate between these samples 7665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian // this cannot change because the mul below rely on it. 7765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int pLerpBits = 15; 7865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const int pShift = kNumPhaseBits - coefsBits - pLerpBits; // 11 7965ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const uint32_t pMask = ((1<<pLerpBits)-1) << pShift; // 0x7fff << 11 8065ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 8165ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian // number of zero-crossing on each side 8265ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian static const unsigned int halfNumCoefs = RESAMPLE_FIR_NUM_COEF; 8365ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian}; 8465ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 8565ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian// ---------------------------------------------------------------------------- 8665ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian}; // namespace android 8765ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian 8865ab47156e1c7dfcd8cc4266253a5ff30219e7f0Mathias Agopian#endif /*ANDROID_AUDIO_RESAMPLER_SINC_H*/ 89