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