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 "Biquad.h" |
29 | #include "BiquadProcessor.h" |
30 | |
31 | namespace WebCore { |
32 | |
33 | class BiquadProcessor; |
34 | |
35 | // BiquadDSPKernel is an AudioDSPKernel and is responsible for filtering one channel of a BiquadProcessor using a Biquad object. |
36 | |
37 | class BiquadDSPKernel final : public AudioDSPKernel { |
38 | public: |
39 | explicit BiquadDSPKernel(BiquadProcessor* processor) |
40 | : AudioDSPKernel(processor) |
41 | { |
42 | } |
43 | |
44 | // AudioDSPKernel |
45 | void process(const float* source, float* dest, size_t framesToProcess) override; |
46 | void reset() override { m_biquad.reset(); } |
47 | |
48 | // Get the magnitude and phase response of the filter at the given |
49 | // set of frequencies (in Hz). The phase response is in radians. |
50 | void getFrequencyResponse(int nFrequencies, |
51 | const float* frequencyHz, |
52 | float* magResponse, |
53 | float* phaseResponse); |
54 | |
55 | double tailTime() const override; |
56 | double latencyTime() const override; |
57 | |
58 | protected: |
59 | Biquad m_biquad; |
60 | BiquadProcessor* biquadProcessor() { return static_cast<BiquadProcessor*>(processor()); } |
61 | |
62 | // To prevent audio glitches when parameters are changed, |
63 | // dezippering is used to slowly change the parameters. |
64 | // |useSmoothing| implies that we want to update using the |
65 | // smoothed values. Otherwise the final target values are |
66 | // used. If |forceUpdate| is true, we update the coefficients even |
67 | // if they are not dirty. (Used when computing the frequency |
68 | // response.) |
69 | void updateCoefficientsIfNecessary(bool useSmoothing, bool forceUpdate); |
70 | }; |
71 | |
72 | } // namespace WebCore |
73 | |