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 #include "config.h"
26
27 #if ENABLE(WEB_AUDIO)
28
29 #include "BiquadDSPKernel.h"
30
31 #include "BiquadProcessor.h"
32
33 namespace WebCore {
34
process(const float * source,float * destination,size_t framesToProcess)35 void BiquadDSPKernel::process(const float* source, float* destination, size_t framesToProcess)
36 {
37 ASSERT(source && destination && biquadProcessor());
38
39 // Recompute filter coefficients if any of the parameters have changed.
40 // FIXME: as an optimization, implement a way that a Biquad object can simply copy its internal filter coefficients from another Biquad object.
41 // Then re-factor this code to only run for the first BiquadDSPKernel of each BiquadProcessor.
42 if (biquadProcessor()->filterCoefficientsDirty()) {
43 double value1 = biquadProcessor()->parameter1()->smoothedValue();
44 double value2 = biquadProcessor()->parameter2()->smoothedValue();
45
46 // Convert from Hertz to normalized frequency 0 -> 1.
47 double nyquist = this->nyquist();
48 double normalizedValue1 = value1 / nyquist;
49
50 // Configure the biquad with the new filter parameters for the appropriate type of filter.
51 switch (biquadProcessor()->type()) {
52 case BiquadProcessor::LowPass2:
53 m_biquad.setLowpassParams(normalizedValue1, value2);
54 break;
55
56 case BiquadProcessor::HighPass2:
57 m_biquad.setHighpassParams(normalizedValue1, value2);
58 break;
59
60 case BiquadProcessor::LowShelf:
61 m_biquad.setLowShelfParams(normalizedValue1, value2);
62 break;
63
64 // FIXME: add other biquad filter types...
65 case BiquadProcessor::Peaking:
66 case BiquadProcessor::Allpass:
67 case BiquadProcessor::HighShelf:
68 break;
69 }
70 }
71
72 m_biquad.process(source, destination, framesToProcess);
73 }
74
75 } // namespace WebCore
76
77 #endif // ENABLE(WEB_AUDIO)
78