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#include "config.h"
26
27#if ENABLE(WEB_AUDIO)
28
29#include "OfflineAudioDestinationNode.h"
30
31#include "AudioBus.h"
32#include "AudioContext.h"
33#include "HRTFDatabaseLoader.h"
34#include <algorithm>
35#include <wtf/Threading.h>
36
37using namespace std;
38
39namespace WebCore {
40
41const size_t renderQuantumSize = 128;
42
43OfflineAudioDestinationNode::OfflineAudioDestinationNode(AudioContext* context, AudioBuffer* renderTarget)
44    : AudioDestinationNode(context, renderTarget->sampleRate())
45    , m_renderTarget(renderTarget)
46    , m_startedRendering(false)
47{
48    m_renderBus = adoptPtr(new AudioBus(renderTarget->numberOfChannels(), renderQuantumSize));
49
50    initialize();
51}
52
53OfflineAudioDestinationNode::~OfflineAudioDestinationNode()
54{
55    uninitialize();
56}
57
58void OfflineAudioDestinationNode::initialize()
59{
60    if (isInitialized())
61        return;
62
63    AudioNode::initialize();
64}
65
66void OfflineAudioDestinationNode::uninitialize()
67{
68    if (!isInitialized())
69        return;
70
71    AudioNode::uninitialize();
72}
73
74void OfflineAudioDestinationNode::startRendering()
75{
76    ASSERT(isMainThread());
77    ASSERT(m_renderTarget.get());
78    if (!m_renderTarget.get())
79        return;
80
81    if (!m_startedRendering) {
82        m_startedRendering = true;
83        m_renderThread = createThread(OfflineAudioDestinationNode::renderEntry, this, "offline renderer");
84    }
85}
86
87// Do offline rendering in this thread.
88void* OfflineAudioDestinationNode::renderEntry(void* threadData)
89{
90    OfflineAudioDestinationNode* destinationNode = reinterpret_cast<OfflineAudioDestinationNode*>(threadData);
91    ASSERT(destinationNode);
92    destinationNode->render();
93
94    return 0;
95}
96
97void OfflineAudioDestinationNode::render()
98{
99    ASSERT(!isMainThread());
100    ASSERT(m_renderBus.get());
101    if (!m_renderBus.get())
102        return;
103
104    bool channelsMatch = m_renderBus->numberOfChannels() == m_renderTarget->numberOfChannels();
105    ASSERT(channelsMatch);
106    if (!channelsMatch)
107        return;
108
109    bool isRenderBusAllocated = m_renderBus->length() >= renderQuantumSize;
110    ASSERT(isRenderBusAllocated);
111    if (!isRenderBusAllocated)
112        return;
113
114    // Synchronize with HRTFDatabaseLoader.
115    // The database must be loaded before we can proceed.
116    HRTFDatabaseLoader* loader = HRTFDatabaseLoader::loader();
117    ASSERT(loader);
118    if (!loader)
119        return;
120
121    loader->waitForLoaderThreadCompletion();
122
123    // Break up the render target into smaller "render quantize" sized pieces.
124    // Render until we're finished.
125    size_t framesToProcess = m_renderTarget->length();
126    unsigned numberOfChannels = m_renderTarget->numberOfChannels();
127
128    unsigned n = 0;
129    while (framesToProcess > 0) {
130        // Render one render quantum.
131        provideInput(m_renderBus.get(), renderQuantumSize);
132
133        size_t framesAvailableToCopy = min(framesToProcess, renderQuantumSize);
134
135        for (unsigned channelIndex = 0; channelIndex < numberOfChannels; ++channelIndex) {
136            float* source = m_renderBus->channel(channelIndex)->data();
137            float* destination = m_renderTarget->getChannelData(channelIndex)->data();
138            memcpy(destination + n, source, sizeof(float) * framesAvailableToCopy);
139        }
140
141        n += framesAvailableToCopy;
142        framesToProcess -= framesAvailableToCopy;
143    }
144
145    // Our work is done. Let the AudioContext know.
146    callOnMainThread(notifyCompleteDispatch, this);
147}
148
149void OfflineAudioDestinationNode::notifyCompleteDispatch(void* userData)
150{
151    OfflineAudioDestinationNode* destinationNode = static_cast<OfflineAudioDestinationNode*>(userData);
152    ASSERT(destinationNode);
153    if (!destinationNode)
154        return;
155
156    destinationNode->notifyComplete();
157}
158
159void OfflineAudioDestinationNode::notifyComplete()
160{
161    context()->fireCompletionEvent();
162}
163
164} // namespace WebCore
165
166#endif // ENABLE(WEB_AUDIO)
167