1 | /* |
2 | * Copyright (C) 2011, 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 "AudioDSPKernel.h" |
29 | #include "DownSampler.h" |
30 | #include "UpSampler.h" |
31 | #include "WaveShaperProcessor.h" |
32 | #include <memory> |
33 | |
34 | namespace WebCore { |
35 | |
36 | // WaveShaperDSPKernel is an AudioDSPKernel and is responsible for non-linear distortion on one channel. |
37 | |
38 | class WaveShaperDSPKernel final : public AudioDSPKernel { |
39 | public: |
40 | explicit WaveShaperDSPKernel(WaveShaperProcessor*); |
41 | |
42 | // AudioDSPKernel |
43 | void process(const float* source, float* dest, size_t framesToProcess) override; |
44 | void reset() override; |
45 | double tailTime() const override { return 0; } |
46 | double latencyTime() const override; |
47 | |
48 | // Oversampling requires more resources, so let's only allocate them if needed. |
49 | void lazyInitializeOversampling(); |
50 | |
51 | protected: |
52 | // Apply the shaping curve. |
53 | void processCurve(const float* source, float* dest, size_t framesToProcess); |
54 | |
55 | // Use up-sampling, process at the higher sample-rate, then down-sample. |
56 | void processCurve2x(const float* source, float* dest, size_t framesToProcess); |
57 | void processCurve4x(const float* source, float* dest, size_t framesToProcess); |
58 | |
59 | WaveShaperProcessor* waveShaperProcessor() { return static_cast<WaveShaperProcessor*>(processor()); } |
60 | |
61 | // Oversampling. |
62 | std::unique_ptr<AudioFloatArray> m_tempBuffer; |
63 | std::unique_ptr<AudioFloatArray> m_tempBuffer2; |
64 | std::unique_ptr<UpSampler> m_upSampler; |
65 | std::unique_ptr<DownSampler> m_downSampler; |
66 | std::unique_ptr<UpSampler> m_upSampler2; |
67 | std::unique_ptr<DownSampler> m_downSampler2; |
68 | }; |
69 | |
70 | } // namespace WebCore |
71 | |