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 "modules/webaudio/AudioNodeInput.h" 30 31 #include "modules/webaudio/AudioContext.h" 32 #include "modules/webaudio/AudioNodeOutput.h" 33 #include <algorithm> 34 35 using namespace std; 36 37 namespace WebCore { 38 39 AudioNodeInput::AudioNodeInput(AudioNode* node) 40 : AudioSummingJunction(node->context()) 41 , m_node(node) 42 { 43 // Set to mono by default. 44 m_internalSummingBus = AudioBus::create(1, AudioNode::ProcessingSizeInFrames); 45 } 46 47 void AudioNodeInput::connect(AudioNodeOutput* output) 48 { 49 ASSERT(context()->isGraphOwner()); 50 51 ASSERT(output && node()); 52 if (!output || !node()) 53 return; 54 55 // Check if we're already connected to this output. 56 if (m_outputs.contains(output)) 57 return; 58 59 output->addInput(this); 60 m_outputs.add(output); 61 changedOutputs(); 62 63 // Sombody has just connected to us, so count it as a reference. 64 node()->ref(AudioNode::RefTypeConnection); 65 } 66 67 void AudioNodeInput::disconnect(AudioNodeOutput* output) 68 { 69 ASSERT(context()->isGraphOwner()); 70 71 ASSERT(output && node()); 72 if (!output || !node()) 73 return; 74 75 // First try to disconnect from "active" connections. 76 if (m_outputs.contains(output)) { 77 m_outputs.remove(output); 78 changedOutputs(); 79 output->removeInput(this); 80 node()->deref(AudioNode::RefTypeConnection); // Note: it's important to return immediately after all deref() calls since the node may be deleted. 81 return; 82 } 83 84 // Otherwise, try to disconnect from disabled connections. 85 if (m_disabledOutputs.contains(output)) { 86 m_disabledOutputs.remove(output); 87 output->removeInput(this); 88 node()->deref(AudioNode::RefTypeConnection); // Note: it's important to return immediately after all deref() calls since the node may be deleted. 89 return; 90 } 91 92 ASSERT_NOT_REACHED(); 93 } 94 95 void AudioNodeInput::disable(AudioNodeOutput* output) 96 { 97 ASSERT(context()->isGraphOwner()); 98 99 ASSERT(output && node()); 100 if (!output || !node()) 101 return; 102 103 ASSERT(m_outputs.contains(output)); 104 105 m_disabledOutputs.add(output); 106 m_outputs.remove(output); 107 changedOutputs(); 108 109 // Propagate disabled state to outputs. 110 node()->disableOutputsIfNecessary(); 111 } 112 113 void AudioNodeInput::enable(AudioNodeOutput* output) 114 { 115 ASSERT(context()->isGraphOwner()); 116 117 ASSERT(output && node()); 118 if (!output || !node()) 119 return; 120 121 ASSERT(m_disabledOutputs.contains(output)); 122 123 // Move output from disabled list to active list. 124 m_outputs.add(output); 125 m_disabledOutputs.remove(output); 126 changedOutputs(); 127 128 // Propagate enabled state to outputs. 129 node()->enableOutputsIfNecessary(); 130 } 131 132 void AudioNodeInput::didUpdate() 133 { 134 node()->checkNumberOfChannelsForInput(this); 135 } 136 137 void AudioNodeInput::updateInternalBus() 138 { 139 ASSERT(context()->isAudioThread() && context()->isGraphOwner()); 140 141 unsigned numberOfInputChannels = numberOfChannels(); 142 143 if (numberOfInputChannels == m_internalSummingBus->numberOfChannels()) 144 return; 145 146 m_internalSummingBus = AudioBus::create(numberOfInputChannels, AudioNode::ProcessingSizeInFrames); 147 } 148 149 unsigned AudioNodeInput::numberOfChannels() const 150 { 151 AudioNode::ChannelCountMode mode = node()->internalChannelCountMode(); 152 if (mode == AudioNode::Explicit) 153 return node()->channelCount(); 154 155 // Find the number of channels of the connection with the largest number of channels. 156 unsigned maxChannels = 1; // one channel is the minimum allowed 157 158 for (HashSet<AudioNodeOutput*>::iterator i = m_outputs.begin(); i != m_outputs.end(); ++i) { 159 AudioNodeOutput* output = *i; 160 // Use output()->numberOfChannels() instead of output->bus()->numberOfChannels(), 161 // because the calling of AudioNodeOutput::bus() is not safe here. 162 maxChannels = max(maxChannels, output->numberOfChannels()); 163 } 164 165 if (mode == AudioNode::ClampedMax) 166 maxChannels = min(maxChannels, static_cast<unsigned>(node()->channelCount())); 167 168 return maxChannels; 169 } 170 171 AudioBus* AudioNodeInput::bus() 172 { 173 ASSERT(context()->isAudioThread()); 174 175 // Handle single connection specially to allow for in-place processing. 176 if (numberOfRenderingConnections() == 1 && node()->internalChannelCountMode() == AudioNode::Max) 177 return renderingOutput(0)->bus(); 178 179 // Multiple connections case or complex ChannelCountMode (or no connections). 180 return internalSummingBus(); 181 } 182 183 AudioBus* AudioNodeInput::internalSummingBus() 184 { 185 ASSERT(context()->isAudioThread()); 186 187 return m_internalSummingBus.get(); 188 } 189 190 void AudioNodeInput::sumAllConnections(AudioBus* summingBus, size_t framesToProcess) 191 { 192 ASSERT(context()->isAudioThread()); 193 194 // We shouldn't be calling this method if there's only one connection, since it's less efficient. 195 ASSERT(numberOfRenderingConnections() > 1 || node()->internalChannelCountMode() != AudioNode::Max); 196 197 ASSERT(summingBus); 198 if (!summingBus) 199 return; 200 201 summingBus->zero(); 202 203 AudioBus::ChannelInterpretation interpretation = node()->internalChannelInterpretation(); 204 205 for (unsigned i = 0; i < numberOfRenderingConnections(); ++i) { 206 AudioNodeOutput* output = renderingOutput(i); 207 ASSERT(output); 208 209 // Render audio from this output. 210 AudioBus* connectionBus = output->pull(0, framesToProcess); 211 212 // Sum, with unity-gain. 213 summingBus->sumFrom(*connectionBus, interpretation); 214 } 215 } 216 217 AudioBus* AudioNodeInput::pull(AudioBus* inPlaceBus, size_t framesToProcess) 218 { 219 ASSERT(context()->isAudioThread()); 220 221 // Handle single connection case. 222 if (numberOfRenderingConnections() == 1 && node()->internalChannelCountMode() == AudioNode::Max) { 223 // The output will optimize processing using inPlaceBus if it's able. 224 AudioNodeOutput* output = this->renderingOutput(0); 225 return output->pull(inPlaceBus, framesToProcess); 226 } 227 228 AudioBus* internalSummingBus = this->internalSummingBus(); 229 230 if (!numberOfRenderingConnections()) { 231 // At least, generate silence if we're not connected to anything. 232 // FIXME: if we wanted to get fancy, we could propagate a 'silent hint' here to optimize the downstream graph processing. 233 internalSummingBus->zero(); 234 return internalSummingBus; 235 } 236 237 // Handle multiple connections case. 238 sumAllConnections(internalSummingBus, framesToProcess); 239 240 return internalSummingBus; 241 } 242 243 } // namespace WebCore 244 245 #endif // ENABLE(WEB_AUDIO) 246
