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bartolsthoorn/MixerHostAudio.m

Created April 3, 2012 20:58
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2012-04-03 22:57:16.770 MixerHost[76183:10703] The stereo stream format for the "guitar" mixer input bus:
2012-04-03 22:57:16.771 MixerHost[76183:10703] Sample Rate: 44100
2012-04-03 22:57:16.772 MixerHost[76183:10703] Format ID: lpcm
2012-04-03 22:57:16.772 MixerHost[76183:10703] Format Flags: C2C
2012-04-03 22:57:16.773 MixerHost[76183:10703] Bytes per Packet: 4
2012-04-03 22:57:16.774 MixerHost[76183:10703] Frames per Packet: 1
2012-04-03 22:57:16.774 MixerHost[76183:10703] Bytes per Frame: 4
2012-04-03 22:57:16.774 MixerHost[76183:10703] Channels per Frame: 2
2012-04-03 22:57:16.775 MixerHost[76183:10703] Bits per Channel: 32
2012-04-03 22:57:16.775 MixerHost[76183:10703] The mono stream format for the "beats" mixer input bus:
2012-04-03 22:57:16.776 MixerHost[76183:10703] Sample Rate: 44100
2012-04-03 22:57:16.777 MixerHost[76183:10703] Format ID: lpcm
2012-04-03 22:57:16.777 MixerHost[76183:10703] Format Flags: C2C
2012-04-03 22:57:16.777 MixerHost[76183:10703] Bytes per Packet: 4
2012-04-03 22:57:19.844 MixerHost[76183:10703] Frames per Packet: 1
2012-04-03 22:57:19.847 MixerHost[76183:10703] Bytes per Frame: 4
2012-04-03 22:57:19.848 MixerHost[76183:10703] Channels per Frame: 1
2012-04-03 22:57:19.848 MixerHost[76183:10703] Bits per Channel: 32
2012-04-03 22:57:19.848 MixerHost[76183:10703] readAudioFilesIntoMemory - file 0
2012-04-03 22:57:20.141 MixerHost[76183:10703] Finished reading file 0 into memory
2012-04-03 22:57:20.144 MixerHost[76183:10703] readAudioFilesIntoMemory - file 1
2012-04-03 22:57:20.413 MixerHost[76183:10703] Finished reading file 1 into memory
2012-04-03 22:57:20.422 MixerHost[76183:10703] Configuring and then initializing audio processing graph
2012-04-03 22:57:20.423 MixerHost[76183:10703] Adding nodes to audio processing graph
2012-04-03 22:57:20.429 MixerHost[76183:10703] Setting mixer unit input bus count to: 2
2012-04-03 22:57:20.433 MixerHost[76183:10703] Setting kAudioUnitProperty_MaximumFramesPerSlice for mixer unit global scope
2012-04-03 22:57:20.434 MixerHost[76183:10703] Registering the render callback with mixer unit input bus 0
2012-04-03 22:57:20.436 MixerHost[76183:10703] Registering the render callback with mixer unit input bus 1
2012-04-03 22:57:20.437 MixerHost[76183:10703] Setting stereo stream format for mixer unit "guitar" input bus
2012-04-03 22:57:20.439 MixerHost[76183:10703] Setting mono stream format for mixer unit "beats" input bus
2012-04-03 22:57:20.442 MixerHost[76183:10703] Setting sample rate for EQ unit output scope
2012-04-03 22:57:20.446 MixerHost[76183:10703] Connecting the mixer output to the input of the EQ!!
2012-04-03 22:57:20.454 MixerHost[76183:10703] Connecting the EQ output to the input of the I/O output element
2012-04-03 22:57:20.455 MixerHost[76183:10703] Audio processing graph state immediately before initializing it:
AudioUnitGraph 0x12997009:
Member Nodes:
node 1: 'auou' 'rioc' 'appl', instance 0x7560660 O
node 2: 'aufx' 'nbeq' 'appl', instance 0x734ef90 O
node 3: 'aumx' 'mcmx' 'appl', instance 0x739c170 O
Connections:
node 3 bus 0 => node 2 bus 0 [ 2 ch, 44100 Hz, 'lpcm' (0x00000029) 32-bit little-endian float, deinterleaved]
node 2 bus 0 => node 1 bus 0 [ 2 ch, 0 Hz, 'lpcm' (0x0000000C) 16-bit little-endian signed integer]
Input Callbacks:
{0x5390, 0x7399f24} => node 3 bus 0 [2 ch, 44100 Hz]
{0x5390, 0x7399f24} => node 3 bus 1 [1 ch, 44100 Hz]
CurrentState:
mLastUpdateError=0, eventsToProcess=F, isRunning=F
2012-04-03 22:57:20.460 MixerHost[76183:10703] Initializing the audio processing graph
2012-04-03 22:57:20.482 MixerHost[76183:10703] *** AUGraphInitialize error: ˇˇ’å FFFFD58C
2012-04-03 22:57:20.484 MixerHost[76183:10703] Bus 0 now on
2012-04-03 22:57:20.485 MixerHost[76183:10703] Bus 1 now on
Raw
MixerHostAudio.m
#pragma mark -
#pragma mark Audio processing graph setup
// This method performs all the work needed to set up the audio processing graph:
// 1. Instantiate and open an audio processing graph
// 2. Obtain the audio unit nodes for the graph
// 3. Configure the Multichannel Mixer unit
// * specify the number of input buses
// * specify the output sample rate
// * specify the maximum frames-per-slice
// 4. Initialize the audio processing graph
- (void) configureAndInitializeAudioProcessingGraph {
NSLog (@"Configuring and then initializing audio processing graph");
OSStatus result = noErr;
//............................................................................
// Create a new audio processing graph.
result = NewAUGraph (&processingGraph);
if (noErr != result) {[self printErrorMessage: @"NewAUGraph" withStatus: result]; return;}
//............................................................................
// Specify the audio unit component descriptions for the audio units to be
// added to the graph.
// I/O unit
AudioComponentDescription iOUnitDescription;
iOUnitDescription.componentType = kAudioUnitType_Output;
iOUnitDescription.componentSubType = kAudioUnitSubType_RemoteIO;
iOUnitDescription.componentManufacturer = kAudioUnitManufacturer_Apple;
iOUnitDescription.componentFlags = 0;
iOUnitDescription.componentFlagsMask = 0;
// EQ unit
AudioComponentDescription EQUnitDescription;
EQUnitDescription.componentType = kAudioUnitType_Effect;
EQUnitDescription.componentSubType = kAudioUnitSubType_NBandEQ;
EQUnitDescription.componentManufacturer = kAudioUnitManufacturer_Apple;
EQUnitDescription.componentFlags = 0;
EQUnitDescription.componentFlagsMask = 0;
// Multichannel mixer unit
AudioComponentDescription MixerUnitDescription;
MixerUnitDescription.componentType = kAudioUnitType_Mixer;
MixerUnitDescription.componentSubType = kAudioUnitSubType_MultiChannelMixer;
MixerUnitDescription.componentManufacturer = kAudioUnitManufacturer_Apple;
MixerUnitDescription.componentFlags = 0;
MixerUnitDescription.componentFlagsMask = 0;
//............................................................................
// Add nodes to the audio processing graph.
NSLog (@"Adding nodes to audio processing graph");
AUNode iONode; // node for I/O unit
AUNode mixerNode; // node for Multichannel Mixer unit
AUNode EQNode;
// Add the nodes to the audio processing graph
// I/O!
result = AUGraphAddNode (
processingGraph,
&iOUnitDescription,
&iONode);
if (noErr != result) {[self printErrorMessage: @"AUGraphNewNode failed for I/O unit" withStatus: result]; return;}
// EQ!
result = AUGraphAddNode (
processingGraph,
&EQUnitDescription,
&EQNode
);
if (noErr != result) {[self printErrorMessage: @"AUGraphNewNode failed for EQ unit" withStatus: result]; return;}
// MIXING!
result = AUGraphAddNode (
processingGraph,
&MixerUnitDescription,
&mixerNode
);
if (noErr != result) {[self printErrorMessage: @"AUGraphNewNode failed for Mixer unit" withStatus: result]; return;}
//............................................................................
// Open the audio processing graph
// Following this call, the audio units are instantiated but not initialized
// (no resource allocation occurs and the audio units are not in a state to
// process audio).
result = AUGraphOpen (processingGraph);
if (noErr != result) {[self printErrorMessage: @"AUGraphOpen" withStatus: result]; return;}
result = AUGraphNodeInfo (
processingGraph,
mixerNode,
NULL,
&mixerUnit
);
//............................................................................
// Obtain the mixer unit instance from its corresponding node.
result = AUGraphNodeInfo (
processingGraph,
EQNode,
NULL,
&EQUnit
);
if (noErr != result) {[self printErrorMessage: @"AUGraphNodeInfo" withStatus: result]; return;}
//............................................................................
// Obtain the EQ unit instance from its corresponding node.
result = AUGraphNodeInfo (
processingGraph,
mixerNode,
NULL,
&mixerUnit
);
if (noErr != result) {[self printErrorMessage: @"AUGraphNodeInfo" withStatus: result]; return;}
//............................................................................
// Multichannel Mixer unit Setup
UInt32 busCount = 2; // bus count for mixer unit input
UInt32 guitarBus = 0; // mixer unit bus 0 will be stereo and will take the guitar sound
UInt32 beatsBus = 1; // mixer unit bus 1 will be mono and will take the beats sound
NSLog (@"Setting mixer unit input bus count to: %lu", busCount);
result = AudioUnitSetProperty (
mixerUnit,
kAudioUnitProperty_ElementCount,
kAudioUnitScope_Input,
0,
&busCount,
sizeof (busCount)
);
if (noErr != result) {[self printErrorMessage: @"AudioUnitSetProperty (set mixer unit bus count)" withStatus: result]; return;}
NSLog (@"Setting kAudioUnitProperty_MaximumFramesPerSlice for mixer unit global scope");
// Increase the maximum frames per slice allows the mixer unit to accommodate the
// larger slice size used when the screen is locked.
UInt32 maximumFramesPerSlice = 4096;
result = AudioUnitSetProperty (
mixerUnit,
kAudioUnitProperty_MaximumFramesPerSlice,
kAudioUnitScope_Global,
0,
&maximumFramesPerSlice,
sizeof (maximumFramesPerSlice)
);
if (noErr != result) {[self printErrorMessage: @"AudioUnitSetProperty (set mixer unit input stream format)" withStatus: result]; return;}
// Attach the input render callback and context to each input bus
for (UInt16 busNumber = 0; busNumber < busCount; ++busNumber) {
// Setup the struture that contains the input render callback
AURenderCallbackStruct inputCallbackStruct;
inputCallbackStruct.inputProc = &inputRenderCallback;
inputCallbackStruct.inputProcRefCon = soundStructArray;
NSLog (@"Registering the render callback with mixer unit input bus %u", busNumber);
// Set a callback for the specified node's specified input
result = AUGraphSetNodeInputCallback (
processingGraph,
mixerNode,
busNumber,
&inputCallbackStruct
);
if (noErr != result) {[self printErrorMessage: @"AUGraphSetNodeInputCallback" withStatus: result]; return;}
}
NSLog (@"Setting stereo stream format for mixer unit \"guitar\" input bus");
result = AudioUnitSetProperty (
mixerUnit,
kAudioUnitProperty_StreamFormat,
kAudioUnitScope_Input,
guitarBus,
&stereoStreamFormat,
sizeof (stereoStreamFormat)
);
if (noErr != result) {[self printErrorMessage: @"AudioUnitSetProperty (set mixer unit guitar input bus stream format)" withStatus: result];return;}
NSLog (@"Setting mono stream format for mixer unit \"beats\" input bus");
result = AudioUnitSetProperty (
mixerUnit,
kAudioUnitProperty_StreamFormat,
kAudioUnitScope_Input,
beatsBus,
&monoStreamFormat,
sizeof (monoStreamFormat)
);
if (noErr != result) {[self printErrorMessage: @"AudioUnitSetProperty (set mixer unit beats input bus stream format)" withStatus: result];return;}
NSLog (@"Setting sample rate for EQ unit output scope");
result = AudioUnitSetProperty (
EQUnit,
kAudioUnitProperty_SampleRate,
kAudioUnitScope_Output,
0,
&graphSampleRate,
sizeof (graphSampleRate)
);
if (noErr != result) {[self printErrorMessage: @"AudioUnitSetProperty (set EQ unit output stream format)" withStatus: result]; return;}
//............................................................................
// Connect the nodes of the audio processing graph
NSLog (@"Connecting the mixer output to the input of the EQ!!");
result = AUGraphConnectNodeInput (
processingGraph,
mixerNode, // source node
0, // source node output bus number
EQNode, // destination node
0 // desintation node input bus number
);
if (noErr != result) {[self printErrorMessage: @"AUGraphConnectNodeInput" withStatus: result]; return;}
NSLog (@"Connecting the EQ output to the input of the I/O output element");
result = AUGraphConnectNodeInput (
processingGraph,
EQNode, // source node
0, // source node output bus number
iONode, // destination node
0 // desintation node input bus number
);
if (noErr != result) {[self printErrorMessage: @"AUGraphConnectNodeInput" withStatus: result]; return;}
//............................................................................
// Initialize audio processing graph
// Diagnostic code
// Call CAShow if you want to look at the state of the audio processing
// graph.
NSLog (@"Audio processing graph state immediately before initializing it:");
CAShow (processingGraph);
NSLog (@"Initializing the audio processing graph");
// Initialize the audio processing graph, configure audio data stream formats for
// each input and output, and validate the connections between audio units.
result = AUGraphInitialize (processingGraph);
if (noErr != result) {[self printErrorMessage: @"AUGraphInitialize" withStatus: result]; return;}
}
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