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#pragma once
26
27#include "AudioDSPKernel.h"
28#include "AudioDSPKernelProcessor.h"
29#include "AudioNode.h"
30#include "AudioParam.h"
31#include "Biquad.h"
32#include <memory>
33#include <wtf/RefPtr.h>
34
35namespace WebCore {
36
37// BiquadProcessor is an AudioDSPKernelProcessor which uses Biquad objects to implement several common filters.
38
39enum class BiquadFilterType {
40 Lowpass,
41 Highpass,
42 Bandpass,
43 Lowshelf,
44 Highshelf,
45 Peaking,
46 Notch,
47 Allpass
48};
49
50class BiquadProcessor final : public AudioDSPKernelProcessor {
51 WTF_MAKE_FAST_ALLOCATED;
52public:
53 BiquadProcessor(AudioContext&, float sampleRate, size_t numberOfChannels, bool autoInitialize);
54
55 virtual ~BiquadProcessor();
56
57 std::unique_ptr<AudioDSPKernel> createKernel() override;
58
59 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 BiquadFilterType type() const { return m_type; }
79 void setType(BiquadFilterType);
80
81private:
82 BiquadFilterType 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