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 | |
35 | namespace WebCore { |
36 | |
37 | // BiquadProcessor is an AudioDSPKernelProcessor which uses Biquad objects to implement several common filters. |
38 | |
39 | enum class BiquadFilterType { |
40 | Lowpass, |
41 | Highpass, |
42 | Bandpass, |
43 | Lowshelf, |
44 | Highshelf, |
45 | Peaking, |
46 | Notch, |
47 | Allpass |
48 | }; |
49 | |
50 | class BiquadProcessor final : public AudioDSPKernelProcessor { |
51 | WTF_MAKE_FAST_ALLOCATED; |
52 | public: |
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 | |
81 | private: |
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 | |