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 are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32
33 #if ENABLE(WEB_AUDIO)
34
35 #include "AudioDSPKernelProcessor.h"
36
37 #include "AudioDSPKernel.h"
38
39 namespace WebCore {
40
41 // setNumberOfChannels() may later be called if the object is not yet in an "initialized" state.
AudioDSPKernelProcessor(double sampleRate,unsigned numberOfChannels)42 AudioDSPKernelProcessor::AudioDSPKernelProcessor(double sampleRate, unsigned numberOfChannels)
43 : AudioProcessor(sampleRate)
44 , m_numberOfChannels(numberOfChannels)
45 , m_hasJustReset(true)
46 {
47 }
48
initialize()49 void AudioDSPKernelProcessor::initialize()
50 {
51 if (isInitialized())
52 return;
53
54 ASSERT(!m_kernels.size());
55
56 // Create processing kernels, one per channel.
57 for (unsigned i = 0; i < numberOfChannels(); ++i)
58 m_kernels.append(createKernel());
59
60 m_initialized = true;
61 }
62
uninitialize()63 void AudioDSPKernelProcessor::uninitialize()
64 {
65 if (!isInitialized())
66 return;
67
68 m_kernels.clear();
69
70 m_initialized = false;
71 }
72
process(AudioBus * source,AudioBus * destination,size_t framesToProcess)73 void AudioDSPKernelProcessor::process(AudioBus* source, AudioBus* destination, size_t framesToProcess)
74 {
75 ASSERT(source && destination);
76 if (!source || !destination)
77 return;
78
79 if (!isInitialized()) {
80 destination->zero();
81 return;
82 }
83
84 bool channelCountMatches = source->numberOfChannels() == destination->numberOfChannels() && source->numberOfChannels() == m_kernels.size();
85 ASSERT(channelCountMatches);
86 if (!channelCountMatches)
87 return;
88
89 for (unsigned i = 0; i < m_kernels.size(); ++i)
90 m_kernels[i]->process(source->channel(i)->data(), destination->channel(i)->data(), framesToProcess);
91 }
92
93 // Resets filter state
reset()94 void AudioDSPKernelProcessor::reset()
95 {
96 if (!isInitialized())
97 return;
98
99 // Forces snap to parameter values - first time.
100 // Any processing depending on this value must set it to false at the appropriate time.
101 m_hasJustReset = true;
102
103 for (unsigned i = 0; i < m_kernels.size(); ++i)
104 m_kernels[i]->reset();
105 }
106
setNumberOfChannels(unsigned numberOfChannels)107 void AudioDSPKernelProcessor::setNumberOfChannels(unsigned numberOfChannels)
108 {
109 ASSERT(!isInitialized());
110 if (!isInitialized())
111 m_numberOfChannels = numberOfChannels;
112 }
113
114 } // namespace WebCore
115
116 #endif // ENABLE(WEB_AUDIO)
117