/* * Copyright (C) 2007 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. */ #ifndef ANDROID_AUDIO_RESAMPLER_SINC_H #define ANDROID_AUDIO_RESAMPLER_SINC_H #include #include #include #include namespace android { typedef const int32_t * (*readCoefficientsFn)(bool upDownSample); typedef int32_t (*readResampleFirNumCoeffFn)(); typedef int32_t (*readResampleFirLerpIntBitsFn)(); // ---------------------------------------------------------------------------- class AudioResamplerSinc : public AudioResampler { public: AudioResamplerSinc(int inChannelCount, int32_t sampleRate, src_quality quality = HIGH_QUALITY); virtual ~AudioResamplerSinc(); virtual size_t resample(int32_t* out, size_t outFrameCount, AudioBufferProvider* provider); private: void init(); virtual void setVolume(float left, float right); template size_t resample(int32_t* out, size_t outFrameCount, AudioBufferProvider* provider); template inline void filterCoefficient( int32_t* out, uint32_t phase, const int16_t *samples, uint32_t vRL); template inline void interpolate( int32_t& l, int32_t& r, const int32_t* coefs, size_t offset, int32_t lerp, const int16_t* samples); template inline void read(int16_t*& impulse, uint32_t& phaseFraction, const int16_t* in, size_t inputIndex); int16_t *mState; int16_t *mImpulse; int16_t *mRingFull; int32_t mVolumeSIMD[2]; const int32_t * mFirCoefs; static const uint32_t mFirCoefsDown[]; static const uint32_t mFirCoefsUp[]; // ---------------------------------------------------------------------------- static const int32_t RESAMPLE_FIR_NUM_COEF = 8; static const int32_t RESAMPLE_FIR_LERP_INT_BITS = 7; struct Constants { int coefsBits; int cShift; uint32_t cMask; int pShift; uint32_t pMask; // number of zero-crossing on each side unsigned int halfNumCoefs; }; static Constants highQualityConstants; static Constants veryHighQualityConstants; const Constants *mConstants; // points to appropriate set of coefficient parameters static void init_routine(); }; // ---------------------------------------------------------------------------- } // namespace android #endif /*ANDROID_AUDIO_RESAMPLER_SINC_H*/