1/* 2 * Copyright (C) 2010, Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY 17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25#ifndef BiquadProcessor_h 26#define BiquadProcessor_h 27 28#include "AudioDSPKernel.h" 29#include "AudioDSPKernelProcessor.h" 30#include "AudioNode.h" 31#include "AudioParam.h" 32#include "Biquad.h" 33#include <memory> 34#include <wtf/RefPtr.h> 35 36namespace WebCore { 37 38// BiquadProcessor is an AudioDSPKernelProcessor which uses Biquad objects to implement several common filters. 39 40class BiquadProcessor : public AudioDSPKernelProcessor { 41public: 42 enum FilterType { 43 LowPass = 0, 44 HighPass = 1, 45 BandPass = 2, 46 LowShelf = 3, 47 HighShelf = 4, 48 Peaking = 5, 49 Notch = 6, 50 Allpass = 7 51 }; 52 53 BiquadProcessor(AudioContext*, float sampleRate, size_t numberOfChannels, bool autoInitialize); 54 55 virtual ~BiquadProcessor(); 56 57 virtual std::unique_ptr<AudioDSPKernel> createKernel() override; 58 59 virtual void process(const AudioBus* source, AudioBus* destination, size_t framesToProcess) override; 60 61 // Get the magnitude and phase response of the filter at the given 62 // set of frequencies (in Hz). The phase response is in radians. 63 void getFrequencyResponse(int nFrequencies, 64 const float* frequencyHz, 65 float* magResponse, 66 float* phaseResponse); 67 68 void checkForDirtyCoefficients(); 69 70 bool filterCoefficientsDirty() const { return m_filterCoefficientsDirty; } 71 bool hasSampleAccurateValues() const { return m_hasSampleAccurateValues; } 72 73 AudioParam* parameter1() { return m_parameter1.get(); } 74 AudioParam* parameter2() { return m_parameter2.get(); } 75 AudioParam* parameter3() { return m_parameter3.get(); } 76 AudioParam* parameter4() { return m_parameter4.get(); } 77 78 FilterType type() const { return m_type; } 79 void setType(FilterType); 80 81private: 82 FilterType m_type; 83 84 RefPtr<AudioParam> m_parameter1; 85 RefPtr<AudioParam> m_parameter2; 86 RefPtr<AudioParam> m_parameter3; 87 RefPtr<AudioParam> m_parameter4; 88 89 // so DSP kernels know when to re-compute coefficients 90 bool m_filterCoefficientsDirty; 91 92 // Set to true if any of the filter parameters are sample-accurate. 93 bool m_hasSampleAccurateValues; 94}; 95 96} // namespace WebCore 97 98#endif // BiquadProcessor_h 99