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 "AudioArray.h" |
28 | #include "FFTFrame.h" |
29 | #include <JavaScriptCore/Float32Array.h> |
30 | #include <JavaScriptCore/Uint8Array.h> |
31 | #include <memory> |
32 | #include <wtf/Forward.h> |
33 | #include <wtf/Noncopyable.h> |
34 | |
35 | namespace WebCore { |
36 | |
37 | class AudioBus; |
38 | |
39 | class RealtimeAnalyser { |
40 | WTF_MAKE_NONCOPYABLE(RealtimeAnalyser); |
41 | WTF_MAKE_FAST_ALLOCATED; |
42 | public: |
43 | RealtimeAnalyser(); |
44 | virtual ~RealtimeAnalyser(); |
45 | |
46 | void reset(); |
47 | |
48 | size_t fftSize() const { return m_fftSize; } |
49 | bool setFftSize(size_t); |
50 | |
51 | unsigned frequencyBinCount() const { return m_fftSize / 2; } |
52 | |
53 | void setMinDecibels(double k) { m_minDecibels = k; } |
54 | double minDecibels() const { return m_minDecibels; } |
55 | |
56 | void setMaxDecibels(double k) { m_maxDecibels = k; } |
57 | double maxDecibels() const { return m_maxDecibels; } |
58 | |
59 | void setSmoothingTimeConstant(double k) { m_smoothingTimeConstant = k; } |
60 | double smoothingTimeConstant() const { return m_smoothingTimeConstant; } |
61 | |
62 | void getFloatFrequencyData(JSC::Float32Array*); |
63 | void getByteFrequencyData(JSC::Uint8Array*); |
64 | void getByteTimeDomainData(JSC::Uint8Array*); |
65 | |
66 | // The audio thread writes input data here. |
67 | void writeInput(AudioBus*, size_t framesToProcess); |
68 | |
69 | static const double DefaultSmoothingTimeConstant; |
70 | static const double DefaultMinDecibels; |
71 | static const double DefaultMaxDecibels; |
72 | |
73 | static const unsigned DefaultFFTSize; |
74 | static const unsigned MinFFTSize; |
75 | static const unsigned MaxFFTSize; |
76 | static const unsigned InputBufferSize; |
77 | |
78 | private: |
79 | // The audio thread writes the input audio here. |
80 | AudioFloatArray m_inputBuffer; |
81 | unsigned m_writeIndex; |
82 | |
83 | size_t m_fftSize; |
84 | std::unique_ptr<FFTFrame> m_analysisFrame; |
85 | void doFFTAnalysis(); |
86 | |
87 | // doFFTAnalysis() stores the floating-point magnitude analysis data here. |
88 | AudioFloatArray m_magnitudeBuffer; |
89 | AudioFloatArray& magnitudeBuffer() { return m_magnitudeBuffer; } |
90 | |
91 | // A value between 0 and 1 which averages the previous version of m_magnitudeBuffer with the current analysis magnitude data. |
92 | double m_smoothingTimeConstant; |
93 | |
94 | // The range used when converting when using getByteFrequencyData(). |
95 | double m_minDecibels; |
96 | double m_maxDecibels; |
97 | }; |
98 | |
99 | } // namespace WebCore |
100 | |