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 "ChannelSplitterNode.h"
30
31#include "AudioContext.h"
32#include "AudioNodeInput.h"
33#include "AudioNodeOutput.h"
34#include <wtf/IsoMallocInlines.h>
35
36namespace WebCore {
37
38WTF_MAKE_ISO_ALLOCATED_IMPL(ChannelSplitterNode);
39
40RefPtr<ChannelSplitterNode> ChannelSplitterNode::create(AudioContext& context, float sampleRate, unsigned numberOfOutputs)
41{
42 if (!numberOfOutputs || numberOfOutputs > AudioContext::maxNumberOfChannels())
43 return nullptr;
44
45 return adoptRef(*new ChannelSplitterNode(context, sampleRate, numberOfOutputs));
46}
47
48ChannelSplitterNode::ChannelSplitterNode(AudioContext& context, float sampleRate, unsigned numberOfOutputs)
49 : AudioNode(context, sampleRate)
50{
51 setNodeType(NodeTypeChannelSplitter);
52
53 addInput(std::make_unique<AudioNodeInput>(this));
54
55 // Create a fixed number of outputs (able to handle the maximum number of channels fed to an input).
56 for (unsigned i = 0; i < numberOfOutputs; ++i)
57 addOutput(std::make_unique<AudioNodeOutput>(this, 1));
58
59 initialize();
60}
61
62void ChannelSplitterNode::process(size_t framesToProcess)
63{
64 AudioBus* source = input(0)->bus();
65 ASSERT(source);
66 ASSERT_UNUSED(framesToProcess, framesToProcess == source->length());
67
68 unsigned numberOfSourceChannels = source->numberOfChannels();
69
70 for (unsigned i = 0; i < numberOfOutputs(); ++i) {
71 AudioBus* destination = output(i)->bus();
72 ASSERT(destination);
73
74 if (i < numberOfSourceChannels) {
75 // Split the channel out if it exists in the source.
76 // It would be nice to avoid the copy and simply pass along pointers, but this becomes extremely difficult with fanout and fanin.
77 destination->channel(0)->copyFrom(source->channel(i));
78 } else if (output(i)->renderingFanOutCount() > 0) {
79 // Only bother zeroing out the destination if it's connected to anything
80 destination->zero();
81 }
82 }
83}
84
85void ChannelSplitterNode::reset()
86{
87}
88
89} // namespace WebCore
90
91#endif // ENABLE(WEB_AUDIO)
92