| /* |
| * Copyright (C) 2010 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of Apple Inc. ("Apple") nor the names of |
| * its contributors may be used to endorse or promote products derived |
| * from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "AudioDestinationCocoa.h" |
| |
| #if ENABLE(WEB_AUDIO) && PLATFORM(MAC) |
| |
| #include "AudioBus.h" |
| #include "VectorMath.h" |
| #include <CoreAudio/AudioHardware.h> |
| |
| namespace WebCore { |
| |
| void AudioDestinationCocoa::configure() |
| { |
| // Open and initialize DefaultOutputUnit |
| AudioComponent comp; |
| AudioComponentDescription desc; |
| |
| desc.componentType = kAudioUnitType_Output; |
| desc.componentSubType = kAudioUnitSubType_DefaultOutput; |
| desc.componentManufacturer = kAudioUnitManufacturer_Apple; |
| desc.componentFlags = 0; |
| desc.componentFlagsMask = 0; |
| comp = AudioComponentFindNext(0, &desc); |
| |
| ASSERT(comp); |
| |
| OSStatus result = AudioComponentInstanceNew(comp, &outputUnit()); |
| ASSERT(!result); |
| |
| result = AudioUnitInitialize(outputUnit()); |
| ASSERT(!result); |
| |
| // Set render callback |
| AURenderCallbackStruct input; |
| input.inputProc = inputProc; |
| input.inputProcRefCon = this; |
| result = AudioUnitSetProperty(outputUnit(), kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Global, 0, &input, sizeof(input)); |
| ASSERT(!result); |
| |
| // Set stream format |
| AudioStreamBasicDescription streamFormat; |
| setAudioStreamBasicDescription(streamFormat, sampleRate()); |
| |
| result = AudioUnitSetProperty(outputUnit(), kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, (void*)&streamFormat, sizeof(AudioStreamBasicDescription)); |
| ASSERT(!result); |
| } |
| |
| void AudioDestinationCocoa::processBusAfterRender(AudioBus& bus, UInt32 numberOfFrames) |
| { |
| const float kLowThreshold = -1; |
| const float kHighThreshold = 1; |
| // Clamp values at 0db (i.e., [-1.0, 1.0]) |
| for (unsigned i = 0; i < bus.numberOfChannels(); ++i) { |
| auto* channel = bus.channel(i); |
| if (!channel->isSilent()) |
| VectorMath::vclip(channel->data(), 1, &kLowThreshold, &kHighThreshold, channel->mutableData(), 1, numberOfFrames); |
| } |
| } |
| |
| } // namespace WebCore |
| |
| #endif // ENABLE(WEB_AUDIO) && PLATFORM(MAC) |