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      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  *
      8  * 1.  Redistributions of source code must retain the above copyright
      9  *     notice, this list of conditions and the following disclaimer.
     10  * 2.  Redistributions in binary form must reproduce the above copyright
     11  *     notice, this list of conditions and the following disclaimer in the
     12  *     documentation and/or other materials provided with the distribution.
     13  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
     14  *     its contributors may be used to endorse or promote products derived
     15  *     from this software without specific prior written permission.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
     18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
     21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 #include "config.h"
     30 
     31 #if ENABLE(WEB_AUDIO)
     32 
     33 #include "AudioDestinationMac.h"
     34 
     35 #include "AudioSourceProvider.h"
     36 #include <CoreAudio/AudioHardware.h>
     37 
     38 namespace WebCore {
     39 
     40 const int kBufferSize = 128;
     41 
     42 // Factory method: Mac-implementation
     43 PassOwnPtr<AudioDestination> AudioDestination::create(AudioSourceProvider& provider, double sampleRate)
     44 {
     45     return adoptPtr(new AudioDestinationMac(provider, sampleRate));
     46 }
     47 
     48 double AudioDestination::hardwareSampleRate()
     49 {
     50     // Determine the default output device's sample-rate.
     51     AudioDeviceID deviceID = kAudioDeviceUnknown;
     52     UInt32 infoSize = sizeof(deviceID);
     53 
     54     AudioObjectPropertyAddress defaultOutputDeviceAddress = { kAudioHardwarePropertyDefaultOutputDevice, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };
     55     OSStatus result = AudioObjectGetPropertyData(kAudioObjectSystemObject, &defaultOutputDeviceAddress, 0, 0, &infoSize, (void*)&deviceID);
     56     if (result)
     57         return 0.0; // error
     58 
     59     Float64 nominalSampleRate;
     60     infoSize = sizeof(Float64);
     61 
     62     AudioObjectPropertyAddress nominalSampleRateAddress = { kAudioDevicePropertyNominalSampleRate, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };
     63     result = AudioObjectGetPropertyData(deviceID, &nominalSampleRateAddress, 0, 0, &infoSize, (void*)&nominalSampleRate);
     64     if (result)
     65         return 0.0; // error
     66 
     67     return nominalSampleRate;
     68 }
     69 
     70 AudioDestinationMac::AudioDestinationMac(AudioSourceProvider& provider, double sampleRate)
     71     : m_outputUnit(0)
     72     , m_provider(provider)
     73     , m_renderBus(2, kBufferSize, false)
     74     , m_sampleRate(sampleRate)
     75     , m_isPlaying(false)
     76 {
     77     // Open and initialize DefaultOutputUnit
     78     Component comp;
     79     ComponentDescription desc;
     80 
     81     desc.componentType = kAudioUnitType_Output;
     82     desc.componentSubType = kAudioUnitSubType_DefaultOutput;
     83     desc.componentManufacturer = kAudioUnitManufacturer_Apple;
     84     desc.componentFlags = 0;
     85     desc.componentFlagsMask = 0;
     86     comp = FindNextComponent(0, &desc);
     87 
     88     ASSERT(comp);
     89 
     90     OSStatus result = OpenAComponent(comp, &m_outputUnit);
     91     ASSERT(!result);
     92 
     93     result = AudioUnitInitialize(m_outputUnit);
     94     ASSERT(!result);
     95 
     96     configure();
     97 }
     98 
     99 AudioDestinationMac::~AudioDestinationMac()
    100 {
    101     if (m_outputUnit)
    102         CloseComponent(m_outputUnit);
    103 }
    104 
    105 void AudioDestinationMac::configure()
    106 {
    107     // Set render callback
    108     AURenderCallbackStruct input;
    109     input.inputProc = inputProc;
    110     input.inputProcRefCon = this;
    111     OSStatus result = AudioUnitSetProperty(m_outputUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Global, 0, &input, sizeof(input));
    112     ASSERT(!result);
    113 
    114     // Set stream format
    115     AudioStreamBasicDescription streamFormat;
    116     streamFormat.mSampleRate = m_sampleRate;
    117     streamFormat.mFormatID = kAudioFormatLinearPCM;
    118     streamFormat.mFormatFlags = kAudioFormatFlagsCanonical | kAudioFormatFlagIsNonInterleaved;
    119     streamFormat.mBitsPerChannel = 8 * sizeof(AudioSampleType);
    120     streamFormat.mChannelsPerFrame = 2;
    121     streamFormat.mFramesPerPacket = 1;
    122     streamFormat.mBytesPerPacket = sizeof(AudioSampleType);
    123     streamFormat.mBytesPerFrame = sizeof(AudioSampleType);
    124 
    125     result = AudioUnitSetProperty(m_outputUnit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, 0, (void*)&streamFormat, sizeof(AudioStreamBasicDescription));
    126     ASSERT(!result);
    127 
    128     // Set the buffer frame size.
    129     UInt32 bufferSize = kBufferSize;
    130     result = AudioUnitSetProperty(m_outputUnit, kAudioDevicePropertyBufferFrameSize, kAudioUnitScope_Output, 0, (void*)&bufferSize, sizeof(bufferSize));
    131     ASSERT(!result);
    132 }
    133 
    134 void AudioDestinationMac::start()
    135 {
    136     OSStatus result = AudioOutputUnitStart(m_outputUnit);
    137 
    138     if (!result)
    139         m_isPlaying = true;
    140 }
    141 
    142 void AudioDestinationMac::stop()
    143 {
    144     OSStatus result = AudioOutputUnitStop(m_outputUnit);
    145 
    146     if (!result)
    147         m_isPlaying = false;
    148 }
    149 
    150 // Pulls on our provider to get rendered audio stream.
    151 OSStatus AudioDestinationMac::render(UInt32 numberOfFrames, AudioBufferList* ioData)
    152 {
    153     AudioBuffer* buffers = ioData->mBuffers;
    154     m_renderBus.setChannelMemory(0, (float*)buffers[0].mData, numberOfFrames);
    155     m_renderBus.setChannelMemory(1, (float*)buffers[1].mData, numberOfFrames);
    156 
    157     m_provider.provideInput(&m_renderBus, numberOfFrames);
    158 
    159     return noErr;
    160 }
    161 
    162 // DefaultOutputUnit callback
    163 OSStatus AudioDestinationMac::inputProc(void* userData, AudioUnitRenderActionFlags*, const AudioTimeStamp*, UInt32 /*busNumber*/, UInt32 numberOfFrames, AudioBufferList* ioData)
    164 {
    165     AudioDestinationMac* audioOutput = static_cast<AudioDestinationMac*>(userData);
    166     return audioOutput->render(numberOfFrames, ioData);
    167 }
    168 
    169 } // namespace WebCore
    170 
    171 #endif // ENABLE(WEB_AUDIO)
    172