/*************************************************************************/ /* audio_driver_coreaudio.cpp */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */ /* */ /* Permission is hereby granted, free of charge, to any person obtaining */ /* a copy of this software and associated documentation files (the */ /* "Software"), to deal in the Software without restriction, including */ /* without limitation the rights to use, copy, modify, merge, publish, */ /* distribute, sublicense, and/or sell copies of the Software, and to */ /* permit persons to whom the Software is furnished to do so, subject to */ /* the following conditions: */ /* */ /* The above copyright notice and this permission notice shall be */ /* included in all copies or substantial portions of the Software. */ /* */ /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/ /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /*************************************************************************/ #ifdef COREAUDIO_ENABLED #include "audio_driver_coreaudio.h" #include "core/os/os.h" #include "core/project_settings.h" #define kOutputBus 0 #define kInputBus 1 #ifdef OSX_ENABLED OSStatus AudioDriverCoreAudio::input_device_address_cb(AudioObjectID inObjectID, UInt32 inNumberAddresses, const AudioObjectPropertyAddress *inAddresses, void *inClientData) { AudioDriverCoreAudio *driver = (AudioDriverCoreAudio *)inClientData; // If our selected device is the Default call set_device to update the // kAudioOutputUnitProperty_CurrentDevice property if (driver->capture_device_name == "Default") { driver->capture_set_device("Default"); } return noErr; } OSStatus AudioDriverCoreAudio::output_device_address_cb(AudioObjectID inObjectID, UInt32 inNumberAddresses, const AudioObjectPropertyAddress *inAddresses, void *inClientData) { AudioDriverCoreAudio *driver = (AudioDriverCoreAudio *)inClientData; // If our selected device is the Default call set_device to update the // kAudioOutputUnitProperty_CurrentDevice property if (driver->device_name == "Default") { driver->set_device("Default"); } return noErr; } #endif Error AudioDriverCoreAudio::init() { AudioComponentDescription desc; zeromem(&desc, sizeof(desc)); desc.componentType = kAudioUnitType_Output; #ifdef OSX_ENABLED desc.componentSubType = kAudioUnitSubType_HALOutput; #else desc.componentSubType = kAudioUnitSubType_RemoteIO; #endif desc.componentManufacturer = kAudioUnitManufacturer_Apple; AudioComponent comp = AudioComponentFindNext(NULL, &desc); ERR_FAIL_COND_V(comp == NULL, FAILED); OSStatus result = AudioComponentInstanceNew(comp, &audio_unit); ERR_FAIL_COND_V(result != noErr, FAILED); #ifdef OSX_ENABLED AudioObjectPropertyAddress prop; prop.mSelector = kAudioHardwarePropertyDefaultOutputDevice; prop.mScope = kAudioObjectPropertyScopeGlobal; prop.mElement = kAudioObjectPropertyElementMaster; result = AudioObjectAddPropertyListener(kAudioObjectSystemObject, &prop, &output_device_address_cb, this); ERR_FAIL_COND_V(result != noErr, FAILED); #endif AudioStreamBasicDescription strdesc; zeromem(&strdesc, sizeof(strdesc)); UInt32 size = sizeof(strdesc); result = AudioUnitGetProperty(audio_unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Output, kOutputBus, &strdesc, &size); ERR_FAIL_COND_V(result != noErr, FAILED); switch (strdesc.mChannelsPerFrame) { case 2: // Stereo case 4: // Surround 3.1 case 6: // Surround 5.1 case 8: // Surround 7.1 channels = strdesc.mChannelsPerFrame; break; default: // Unknown number of channels, default to stereo channels = 2; break; } mix_rate = GLOBAL_GET("audio/mix_rate"); zeromem(&strdesc, sizeof(strdesc)); strdesc.mFormatID = kAudioFormatLinearPCM; strdesc.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger | kLinearPCMFormatFlagIsPacked; strdesc.mChannelsPerFrame = channels; strdesc.mSampleRate = mix_rate; strdesc.mFramesPerPacket = 1; strdesc.mBitsPerChannel = 16; strdesc.mBytesPerFrame = strdesc.mBitsPerChannel * strdesc.mChannelsPerFrame / 8; strdesc.mBytesPerPacket = strdesc.mBytesPerFrame * strdesc.mFramesPerPacket; result = AudioUnitSetProperty(audio_unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, kOutputBus, &strdesc, sizeof(strdesc)); ERR_FAIL_COND_V(result != noErr, FAILED); int latency = GLOBAL_GET("audio/output_latency"); // Sample rate is independent of channels (ref: https://stackoverflow.com/questions/11048825/audio-sample-frequency-rely-on-channels) buffer_frames = closest_power_of_2(latency * mix_rate / 1000); #ifdef OSX_ENABLED result = AudioUnitSetProperty(audio_unit, kAudioDevicePropertyBufferFrameSize, kAudioUnitScope_Global, kOutputBus, &buffer_frames, sizeof(UInt32)); ERR_FAIL_COND_V(result != noErr, FAILED); #endif unsigned int buffer_size = buffer_frames * channels; samples_in.resize(buffer_size); input_buf.resize(buffer_size); print_verbose("CoreAudio: detected " + itos(channels) + " channels"); print_verbose("CoreAudio: audio buffer frames: " + itos(buffer_frames) + " calculated latency: " + itos(buffer_frames * 1000 / mix_rate) + "ms"); AURenderCallbackStruct callback; zeromem(&callback, sizeof(AURenderCallbackStruct)); callback.inputProc = &AudioDriverCoreAudio::output_callback; callback.inputProcRefCon = this; result = AudioUnitSetProperty(audio_unit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, kOutputBus, &callback, sizeof(callback)); ERR_FAIL_COND_V(result != noErr, FAILED); result = AudioUnitInitialize(audio_unit); ERR_FAIL_COND_V(result != noErr, FAILED); if (GLOBAL_GET("audio/enable_audio_input")) { return capture_init(); } return OK; } OSStatus AudioDriverCoreAudio::output_callback(void *inRefCon, AudioUnitRenderActionFlags *ioActionFlags, const AudioTimeStamp *inTimeStamp, UInt32 inBusNumber, UInt32 inNumberFrames, AudioBufferList *ioData) { AudioDriverCoreAudio *ad = (AudioDriverCoreAudio *)inRefCon; if (!ad->active || !ad->try_lock()) { for (unsigned int i = 0; i < ioData->mNumberBuffers; i++) { AudioBuffer *abuf = &ioData->mBuffers[i]; zeromem(abuf->mData, abuf->mDataByteSize); }; return 0; }; ad->start_counting_ticks(); for (unsigned int i = 0; i < ioData->mNumberBuffers; i++) { AudioBuffer *abuf = &ioData->mBuffers[i]; unsigned int frames_left = inNumberFrames; int16_t *out = (int16_t *)abuf->mData; while (frames_left) { unsigned int frames = MIN(frames_left, ad->buffer_frames); ad->audio_server_process(frames, ad->samples_in.ptrw()); for (unsigned int j = 0; j < frames * ad->channels; j++) { out[j] = ad->samples_in[j] >> 16; } frames_left -= frames; out += frames * ad->channels; }; }; ad->stop_counting_ticks(); ad->unlock(); return 0; }; OSStatus AudioDriverCoreAudio::input_callback(void *inRefCon, AudioUnitRenderActionFlags *ioActionFlags, const AudioTimeStamp *inTimeStamp, UInt32 inBusNumber, UInt32 inNumberFrames, AudioBufferList *ioData) { AudioDriverCoreAudio *ad = (AudioDriverCoreAudio *)inRefCon; if (!ad->active) { return 0; } ad->lock(); AudioBufferList bufferList; bufferList.mNumberBuffers = 1; bufferList.mBuffers[0].mData = ad->input_buf.ptrw(); bufferList.mBuffers[0].mNumberChannels = ad->capture_channels; bufferList.mBuffers[0].mDataByteSize = ad->input_buf.size() * sizeof(int16_t); OSStatus result = AudioUnitRender(ad->input_unit, ioActionFlags, inTimeStamp, inBusNumber, inNumberFrames, &bufferList); if (result == noErr) { for (unsigned int i = 0; i < inNumberFrames * ad->capture_channels; i++) { int32_t sample = ad->input_buf[i] << 16; ad->input_buffer_write(sample); if (ad->capture_channels == 1) { // In case input device is single channel convert it to Stereo ad->input_buffer_write(sample); } } } else { ERR_PRINTS("AudioUnitRender failed, code: " + itos(result)); } ad->unlock(); return result; } void AudioDriverCoreAudio::start() { if (!active) { OSStatus result = AudioOutputUnitStart(audio_unit); if (result != noErr) { ERR_PRINTS("AudioOutputUnitStart failed, code: " + itos(result)); } else { active = true; } } }; void AudioDriverCoreAudio::stop() { if (active) { OSStatus result = AudioOutputUnitStop(audio_unit); if (result != noErr) { ERR_PRINTS("AudioOutputUnitStop failed, code: " + itos(result)); } else { active = false; } } } int AudioDriverCoreAudio::get_mix_rate() const { return mix_rate; }; AudioDriver::SpeakerMode AudioDriverCoreAudio::get_speaker_mode() const { return get_speaker_mode_by_total_channels(channels); }; void AudioDriverCoreAudio::lock() { mutex.lock(); }; void AudioDriverCoreAudio::unlock() { mutex.unlock(); }; bool AudioDriverCoreAudio::try_lock() { return mutex.try_lock() == OK; } void AudioDriverCoreAudio::finish() { capture_finish(); if (audio_unit) { OSStatus result; lock(); AURenderCallbackStruct callback; zeromem(&callback, sizeof(AURenderCallbackStruct)); result = AudioUnitSetProperty(audio_unit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, kOutputBus, &callback, sizeof(callback)); if (result != noErr) { ERR_PRINT("AudioUnitSetProperty failed"); } if (active) { result = AudioOutputUnitStop(audio_unit); if (result != noErr) { ERR_PRINT("AudioOutputUnitStop failed"); } active = false; } result = AudioUnitUninitialize(audio_unit); if (result != noErr) { ERR_PRINT("AudioUnitUninitialize failed"); } #ifdef OSX_ENABLED AudioObjectPropertyAddress prop; prop.mSelector = kAudioHardwarePropertyDefaultOutputDevice; prop.mScope = kAudioObjectPropertyScopeGlobal; prop.mElement = kAudioObjectPropertyElementMaster; result = AudioObjectRemovePropertyListener(kAudioObjectSystemObject, &prop, &output_device_address_cb, this); if (result != noErr) { ERR_PRINT("AudioObjectRemovePropertyListener failed"); } #endif result = AudioComponentInstanceDispose(audio_unit); if (result != noErr) { ERR_PRINT("AudioComponentInstanceDispose failed"); } audio_unit = NULL; unlock(); } } Error AudioDriverCoreAudio::capture_init() { AudioComponentDescription desc; zeromem(&desc, sizeof(desc)); desc.componentType = kAudioUnitType_Output; #ifdef OSX_ENABLED desc.componentSubType = kAudioUnitSubType_HALOutput; #else desc.componentSubType = kAudioUnitSubType_RemoteIO; #endif desc.componentManufacturer = kAudioUnitManufacturer_Apple; AudioComponent comp = AudioComponentFindNext(NULL, &desc); ERR_FAIL_COND_V(comp == NULL, FAILED); OSStatus result = AudioComponentInstanceNew(comp, &input_unit); ERR_FAIL_COND_V(result != noErr, FAILED); #ifdef OSX_ENABLED AudioObjectPropertyAddress prop; prop.mSelector = kAudioHardwarePropertyDefaultInputDevice; prop.mScope = kAudioObjectPropertyScopeGlobal; prop.mElement = kAudioObjectPropertyElementMaster; result = AudioObjectAddPropertyListener(kAudioObjectSystemObject, &prop, &input_device_address_cb, this); ERR_FAIL_COND_V(result != noErr, FAILED); #endif UInt32 flag = 1; result = AudioUnitSetProperty(input_unit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Input, kInputBus, &flag, sizeof(flag)); ERR_FAIL_COND_V(result != noErr, FAILED); flag = 0; result = AudioUnitSetProperty(input_unit, kAudioOutputUnitProperty_EnableIO, kAudioUnitScope_Output, kOutputBus, &flag, sizeof(flag)); ERR_FAIL_COND_V(result != noErr, FAILED); UInt32 size; #ifdef OSX_ENABLED AudioDeviceID deviceId; size = sizeof(AudioDeviceID); AudioObjectPropertyAddress property = { kAudioHardwarePropertyDefaultInputDevice, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster }; result = AudioObjectGetPropertyData(kAudioObjectSystemObject, &property, 0, NULL, &size, &deviceId); ERR_FAIL_COND_V(result != noErr, FAILED); result = AudioUnitSetProperty(input_unit, kAudioOutputUnitProperty_CurrentDevice, kAudioUnitScope_Global, 0, &deviceId, sizeof(AudioDeviceID)); ERR_FAIL_COND_V(result != noErr, FAILED); #endif AudioStreamBasicDescription strdesc; zeromem(&strdesc, sizeof(strdesc)); size = sizeof(strdesc); result = AudioUnitGetProperty(input_unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Output, kInputBus, &strdesc, &size); ERR_FAIL_COND_V(result != noErr, FAILED); switch (strdesc.mChannelsPerFrame) { case 1: // Mono capture_channels = 1; break; case 2: // Stereo capture_channels = 2; break; default: // Unknown number of channels, default to stereo capture_channels = 2; break; } mix_rate = GLOBAL_GET("audio/mix_rate"); zeromem(&strdesc, sizeof(strdesc)); strdesc.mFormatID = kAudioFormatLinearPCM; strdesc.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger | kLinearPCMFormatFlagIsPacked; strdesc.mChannelsPerFrame = capture_channels; strdesc.mSampleRate = mix_rate; strdesc.mFramesPerPacket = 1; strdesc.mBitsPerChannel = 16; strdesc.mBytesPerFrame = strdesc.mBitsPerChannel * strdesc.mChannelsPerFrame / 8; strdesc.mBytesPerPacket = strdesc.mBytesPerFrame * strdesc.mFramesPerPacket; result = AudioUnitSetProperty(input_unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Output, kInputBus, &strdesc, sizeof(strdesc)); ERR_FAIL_COND_V(result != noErr, FAILED); AURenderCallbackStruct callback; zeromem(&callback, sizeof(AURenderCallbackStruct)); callback.inputProc = &AudioDriverCoreAudio::input_callback; callback.inputProcRefCon = this; result = AudioUnitSetProperty(input_unit, kAudioOutputUnitProperty_SetInputCallback, kAudioUnitScope_Global, kInputBus, &callback, sizeof(callback)); ERR_FAIL_COND_V(result != noErr, FAILED); result = AudioUnitInitialize(input_unit); ERR_FAIL_COND_V(result != noErr, FAILED); return OK; } void AudioDriverCoreAudio::capture_finish() { if (input_unit) { lock(); AURenderCallbackStruct callback; zeromem(&callback, sizeof(AURenderCallbackStruct)); OSStatus result = AudioUnitSetProperty(input_unit, kAudioOutputUnitProperty_SetInputCallback, kAudioUnitScope_Global, 0, &callback, sizeof(callback)); if (result != noErr) { ERR_PRINT("AudioUnitSetProperty failed"); } result = AudioUnitUninitialize(input_unit); if (result != noErr) { ERR_PRINT("AudioUnitUninitialize failed"); } #ifdef OSX_ENABLED AudioObjectPropertyAddress prop; prop.mSelector = kAudioHardwarePropertyDefaultInputDevice; prop.mScope = kAudioObjectPropertyScopeGlobal; prop.mElement = kAudioObjectPropertyElementMaster; result = AudioObjectRemovePropertyListener(kAudioObjectSystemObject, &prop, &input_device_address_cb, this); if (result != noErr) { ERR_PRINT("AudioObjectRemovePropertyListener failed"); } #endif result = AudioComponentInstanceDispose(input_unit); if (result != noErr) { ERR_PRINT("AudioComponentInstanceDispose failed"); } input_unit = NULL; unlock(); } } Error AudioDriverCoreAudio::capture_start() { input_buffer_init(buffer_frames); OSStatus result = AudioOutputUnitStart(input_unit); if (result != noErr) { ERR_PRINTS("AudioOutputUnitStart failed, code: " + itos(result)); } return OK; } Error AudioDriverCoreAudio::capture_stop() { if (input_unit) { OSStatus result = AudioOutputUnitStop(input_unit); if (result != noErr) { ERR_PRINTS("AudioOutputUnitStop failed, code: " + itos(result)); } } return OK; } #ifdef OSX_ENABLED Array AudioDriverCoreAudio::_get_device_list(bool capture) { Array list; list.push_back("Default"); AudioObjectPropertyAddress prop; prop.mSelector = kAudioHardwarePropertyDevices; prop.mScope = kAudioObjectPropertyScopeGlobal; prop.mElement = kAudioObjectPropertyElementMaster; UInt32 size = 0; AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &prop, 0, NULL, &size); AudioDeviceID *audioDevices = (AudioDeviceID *)memalloc(size); ERR_FAIL_NULL_V_MSG(audioDevices, list, "Out of memory."); AudioObjectGetPropertyData(kAudioObjectSystemObject, &prop, 0, NULL, &size, audioDevices); UInt32 deviceCount = size / sizeof(AudioDeviceID); for (UInt32 i = 0; i < deviceCount; i++) { prop.mScope = capture ? kAudioDevicePropertyScopeInput : kAudioDevicePropertyScopeOutput; prop.mSelector = kAudioDevicePropertyStreamConfiguration; AudioObjectGetPropertyDataSize(audioDevices[i], &prop, 0, NULL, &size); AudioBufferList *bufferList = (AudioBufferList *)memalloc(size); ERR_FAIL_NULL_V_MSG(bufferList, list, "Out of memory."); AudioObjectGetPropertyData(audioDevices[i], &prop, 0, NULL, &size, bufferList); UInt32 channelCount = 0; for (UInt32 j = 0; j < bufferList->mNumberBuffers; j++) channelCount += bufferList->mBuffers[j].mNumberChannels; memfree(bufferList); if (channelCount >= 1) { CFStringRef cfname; size = sizeof(CFStringRef); prop.mSelector = kAudioObjectPropertyName; AudioObjectGetPropertyData(audioDevices[i], &prop, 0, NULL, &size, &cfname); CFIndex length = CFStringGetLength(cfname); CFIndex maxSize = CFStringGetMaximumSizeForEncoding(length, kCFStringEncodingUTF8) + 1; char *buffer = (char *)memalloc(maxSize); ERR_FAIL_NULL_V_MSG(buffer, list, "Out of memory."); if (CFStringGetCString(cfname, buffer, maxSize, kCFStringEncodingUTF8)) { // Append the ID to the name in case we have devices with duplicate name list.push_back(String(buffer) + " (" + itos(audioDevices[i]) + ")"); } memfree(buffer); } } memfree(audioDevices); return list; } void AudioDriverCoreAudio::_set_device(const String &device, bool capture) { AudioDeviceID deviceId; bool found = false; if (device != "Default") { AudioObjectPropertyAddress prop; prop.mSelector = kAudioHardwarePropertyDevices; prop.mScope = kAudioObjectPropertyScopeGlobal; prop.mElement = kAudioObjectPropertyElementMaster; UInt32 size = 0; AudioObjectGetPropertyDataSize(kAudioObjectSystemObject, &prop, 0, NULL, &size); AudioDeviceID *audioDevices = (AudioDeviceID *)memalloc(size); ERR_FAIL_NULL_MSG(audioDevices, "Out of memory."); AudioObjectGetPropertyData(kAudioObjectSystemObject, &prop, 0, NULL, &size, audioDevices); UInt32 deviceCount = size / sizeof(AudioDeviceID); for (UInt32 i = 0; i < deviceCount && !found; i++) { prop.mScope = capture ? kAudioDevicePropertyScopeInput : kAudioDevicePropertyScopeOutput; prop.mSelector = kAudioDevicePropertyStreamConfiguration; AudioObjectGetPropertyDataSize(audioDevices[i], &prop, 0, NULL, &size); AudioBufferList *bufferList = (AudioBufferList *)memalloc(size); ERR_FAIL_NULL_MSG(bufferList, "Out of memory."); AudioObjectGetPropertyData(audioDevices[i], &prop, 0, NULL, &size, bufferList); UInt32 channelCount = 0; for (UInt32 j = 0; j < bufferList->mNumberBuffers; j++) channelCount += bufferList->mBuffers[j].mNumberChannels; memfree(bufferList); if (channelCount >= 1) { CFStringRef cfname; size = sizeof(CFStringRef); prop.mSelector = kAudioObjectPropertyName; AudioObjectGetPropertyData(audioDevices[i], &prop, 0, NULL, &size, &cfname); CFIndex length = CFStringGetLength(cfname); CFIndex maxSize = CFStringGetMaximumSizeForEncoding(length, kCFStringEncodingUTF8) + 1; char *buffer = (char *)memalloc(maxSize); ERR_FAIL_NULL_MSG(buffer, "Out of memory."); if (CFStringGetCString(cfname, buffer, maxSize, kCFStringEncodingUTF8)) { String name = String(buffer) + " (" + itos(audioDevices[i]) + ")"; if (name == device) { deviceId = audioDevices[i]; found = true; } } memfree(buffer); } } memfree(audioDevices); } if (!found) { // If we haven't found the desired device get the system default one UInt32 size = sizeof(AudioDeviceID); UInt32 elem = capture ? kAudioHardwarePropertyDefaultInputDevice : kAudioHardwarePropertyDefaultOutputDevice; AudioObjectPropertyAddress property = { elem, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster }; OSStatus result = AudioObjectGetPropertyData(kAudioObjectSystemObject, &property, 0, NULL, &size, &deviceId); ERR_FAIL_COND(result != noErr); found = true; } if (found) { OSStatus result = AudioUnitSetProperty(capture ? input_unit : audio_unit, kAudioOutputUnitProperty_CurrentDevice, kAudioUnitScope_Global, 0, &deviceId, sizeof(AudioDeviceID)); ERR_FAIL_COND(result != noErr); if (capture) { // Reset audio input to keep synchronisation. input_position = 0; input_size = 0; } } } Array AudioDriverCoreAudio::get_device_list() { return _get_device_list(); } String AudioDriverCoreAudio::get_device() { return device_name; } void AudioDriverCoreAudio::set_device(String device) { device_name = device; if (active) { _set_device(device_name); } } void AudioDriverCoreAudio::capture_set_device(const String &p_name) { capture_device_name = p_name; if (active) { _set_device(capture_device_name, true); } } Array AudioDriverCoreAudio::capture_get_device_list() { return _get_device_list(true); } String AudioDriverCoreAudio::capture_get_device() { return capture_device_name; } #endif AudioDriverCoreAudio::AudioDriverCoreAudio() : audio_unit(NULL), input_unit(NULL), active(false), device_name("Default"), capture_device_name("Default"), mix_rate(0), channels(2), capture_channels(2), buffer_frames(0) { samples_in.clear(); } AudioDriverCoreAudio::~AudioDriverCoreAudio(){}; #endif