AudioContext

java.lang.Object
- net.beadsproject.beads.core.AudioContext

```
public class AudioContext
extends java.lang.Object
```
AudioContext provides the core audio set up for running audio in a Beads project. An AudioContext determines the JavaSound IOAudioFormat used, the IO device, the audio buffer size and the system IO buffer size. An AudioContext also provides a UGen called out, which is the output point for networks of UGens in a Beads project.

Author:

ollie

Field Summary

Fields
Modifier and Type Field and Description

static int DEFAULT_BUFFER_SIZE

Gain out
The root UGen.

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_BUFFER_SIZE`
`Gain`	`out` The root `UGen`.

Constructor Summary

Constructors
Constructor and Description
`AudioContext()` This constructor creates the default AudioContext, which means net.beadsproject.beads.core.io.JavaSoundAudioIO if it can find it, or net.beadsproject.beads.core.io.NonrealtimeIO otherwise.
`AudioContext(AudioIO ioSystem)` Creates a new AudioContext with default audio format and buffer size and the specified `AudioIO`.
`AudioContext(AudioIO ioSystem, int bufferSizeInFrames)` Creates a new AudioContext with default audio format and the specified buffer size and `AudioIO`.
`AudioContext(AudioIO ioSystem, int bufferSizeInFrames, IOAudioFormat audioFormat)` Creates a new AudioContext with the specified buffer size, AudioIO and audio format.
`AudioContext(int bufferSize)` This constructor creates the default AudioContext, which means net.beadsproject.beads.core.io.JavaSoundAudioIO if it can find it, or net.beadsproject.beads.core.io.NonrealtimeIO otherwise.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static IOAudioFormat`	`defaultAudioFormat(int inputs, int outputs)` Generates the default `IOAudioFormat` for AudioContext, with the given number of channels.
`TimeStamp`	`generateTimeStamp(int index)` Generates a TimeStamp with the current time step and the given index into the time step.
`IOAudioFormat`	`getAudioFormat()` Gets the AudioFormat for this AudioContext.
`IOAudioFormat`	`getAudioFormat(int inputs, int outputs)` Generates a new AudioFormat with the same everything as the AudioContext's AudioFormat except for the number of channels.
`UGen`	`getAudioInput()` Returns a UGen which can be used to grab audio from the audio input, as specified by the AudioIO.
`UGen`	`getAudioInput(int[] channels)` Returns a UGen which can be used to grab audio from the audio input, as specified by the AudioIO.
`AudioIO`	`getAudioIO()`
`float[]`	`getBuf()` Gets a buffer from the buffer reserve.
`int`	`getBufferSize()` Gets the buffer size for this AudioContext.
`float[]`	`getCleanBuf()` Gets a zero initialised buffer from the buffer reserve.
`float`	`getSampleRate()` Gets the sample rate for this AudioContext.
`double`	`getTime()` Get the runtime (in ms) since starting.
`long`	`getTimeStep()` Gets the current time step of this AudioContext.
`float[]`	`getZeroBuf()` Gets a pointer to a buffer of length bufferSize, full of zeros.
`AudioContext`	`invokeAfterEveryFrame(Bead target)` Queues the specified Bead to be messaged after every audio frame.
`AudioContext`	`invokeAfterFrame(Bead target)` Queues the specified Bead to be messaged upon the next audio frame completion.
`AudioContext`	`invokeBeforeEveryFrame(Bead target)` Queues the specified Bead to be messaged before every audio frame.
`AudioContext`	`invokeBeforeFrame(Bead target)` Queues the specified bead to be messaged before the next audio frame.
`boolean`	`isRunning()` Checks if this AudioContext is running.
`void`	`logTime(boolean logTime)` Switch on/off logging of time when running in realtime.
`double`	`msToSamples(double msTime)` Converts samples to milliseconds at the current sample rate.
`void`	`postAudioFormatInfo()` Prints AudioFormat information to System.out.
`void`	`printCallChain()` Prints the entire call chain to System.out (equivalent to AudioContext.printCallChain(this.out, 0);)
`static void`	`printCallChain(UGen current, int depth)` Prints a representation of the audio signal chain stemming upwards from the specified UGen to System.out, indented by the specified depth.
`void`	`quickie(UGen ugen)` Convenience method to quickly audition a `UGen`.
`void`	`record(double timeMS, java.lang.String filename)` Tells the AudioContext to record all output for the given millisecond duration, kill the AudioContext, and save the recording to the given file path.
`void`	`reset()` Simply resets the timeStep to zero.
`void`	`runForNMillisecondsNonRealTime(double n)` Runs the AudioContext in non-realtime for n milliseconds (that's n non-realtime milliseconds).
`void`	`runNonRealTime()` Starts the AudioContext running in non-realtime.
`double`	`samplesToMs(double sampleTime)` Converts milliseconds to samples at the current sample rate.
`void`	`start()` Starts the AudioContext running in realtime.
`void`	`stop()` Stops the AudioContext if running either in realtime or non-realtime.
`boolean`	`stopInvokingAfterEveryFrame(Bead target)` Removes the specified Bead from the list of Beads that are messaged after every audio frame.
`boolean`	`stopInvokingBeforeEveryFrame(Bead target)` Removes the specified Bead from the list of Beads that are messaged before every audio frame.
`protected void`	`update()` callback from AudioIO.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_BUFFER_SIZE
```
public static final int DEFAULT_BUFFER_SIZE
```
    See Also:
    
    Constant Field Values
  - out
```
public final Gain out
```
    The root UGen.
- Constructor Detail
  - AudioContext
```
public AudioContext()
```
    This constructor creates the default AudioContext, which means net.beadsproject.beads.core.io.JavaSoundAudioIO if it can find it, or net.beadsproject.beads.core.io.NonrealtimeIO otherwise. To get the former, link to the jaudiolibs-beads.jar file. The libraries are decoupled like this so that the core beads library doesn't depend on JavaSound, which is not supported in various contexts, such as Android. At the moment there are in fact some JavaSound dependencies still to be removed before this process is complete. Pro-users should familiarise themselves with the different IO options, particularly Jack.
  - AudioContext
```
public AudioContext(int bufferSize)
```
    This constructor creates the default AudioContext, which means net.beadsproject.beads.core.io.JavaSoundAudioIO if it can find it, or net.beadsproject.beads.core.io.NonrealtimeIO otherwise. To get the former, link to the jaudiolibs-beads.jar file. The libraries are decoupled like this so that the core beads library doesn't depend on JavaSound, which is not supported in various contexts, such as Android. At the moment there are in fact some JavaSound dependencies still to be removed before this process is complete. Pro-users should familiarise themselves with the different IO options, particularly Jack.
    
    Parameters:
    
    bufferSize - the number of samples calculated during one frame of audio processing. Higher numbers mean more latency and more stability. Typically use powers of 2. Default is 512.
  - AudioContext
```
public AudioContext(AudioIO ioSystem)
```
    Creates a new AudioContext with default audio format and buffer size and the specified AudioIO. The default audio format is 44.1Khz, 16 bit, stereo, signed, bigEndian.
    
    Parameters:
    
    ioSystem - the AudioIO system.
  - AudioContext
```
public AudioContext(AudioIO ioSystem,
                    int bufferSizeInFrames)
```
    Creates a new AudioContext with default audio format and the specified buffer size and AudioIO. The default audio format is 44.1Khz, 16 bit, stereo, signed, bigEndian.
    
    Parameters:
    
    bufferSizeInFrames - the buffer size in samples.
    
    ioSystem - the AudioIO system.
  - AudioContext
```
public AudioContext(AudioIO ioSystem,
                    int bufferSizeInFrames,
                    IOAudioFormat audioFormat)
```
    Creates a new AudioContext with the specified buffer size, AudioIO and audio format.
    
    Parameters:
    
    bufferSizeInFrames - the buffer size in samples.
    
    ioSystem - the AudioIO system.
    
    audioFormat - the audio format, which specifies sample rate, bit depth, number of channels, signedness and byte order.
- Method Detail
  - getAudioInput
```
public UGen getAudioInput(int[] channels)
```
    Returns a UGen which can be used to grab audio from the audio input, as specified by the AudioIO.
    
    Parameters:
    
    channels - an array of ints indicating which channels are required.
    
    Returns:
    
    a UGen which can be used to access audio input.
  - getAudioInput
```
public UGen getAudioInput()
```
    Returns a UGen which can be used to grab audio from the audio input, as specified by the AudioIO. This method returns a UGen with one out for each input channel of the audio input device. For access to specific channels see getAudioInput(int[]).
    
    Returns:
    
    a UGen which can be used to access audio input.
  - update
```
protected void update()
```
    callback from AudioIO.
  - getBuf
```
public float[] getBuf()
```
    Gets a buffer from the buffer reserve. This buffer will be owned by you until the next time step, and you shouldn't attempt to use it outside of the current time step. The length of the buffer is bufferSize, but there is no guarantee as to its contents.
    
    Returns:
    
    buffer of size bufSize, unknown contents.
  - getCleanBuf
```
public float[] getCleanBuf()
```
    Gets a zero initialised buffer from the buffer reserve. This buffer will be owned by you until the next time step, and you shouldn't attempt to use it outside of the current time step. The length of the buffer is bufferSize, and the buffer is full of zeros.
    
    Returns:
    
    buffer of size bufSize, all zeros.
  - getZeroBuf
```
public float[] getZeroBuf()
```
    Gets a pointer to a buffer of length bufferSize, full of zeros. Changing the contents of this buffer would be completely disastrous. If you want a buffer of zeros that you can actually do something with, use getCleanBuf().
    
    Returns:
    
    buffer of size bufSize, all zeros.
  - runNonRealTime
```
public void runNonRealTime()
```
    Starts the AudioContext running in non-realtime. This occurs in the current Thread.
  - runForNMillisecondsNonRealTime
```
public void runForNMillisecondsNonRealTime(double n)
```
    Runs the AudioContext in non-realtime for n milliseconds (that's n non-realtime milliseconds).
    
    Parameters:
    
    n - number of milliseconds.
  - getBufferSize
```
public int getBufferSize()
```
    Gets the buffer size for this AudioContext.
    
    Returns:
    
    Buffer size in samples.
  - getSampleRate
```
public float getSampleRate()
```
    Gets the sample rate for this AudioContext.
    
    Returns:
    
    sample rate in samples per second.
  - getAudioFormat
```
public IOAudioFormat getAudioFormat()
```
    Gets the AudioFormat for this AudioContext.
    
    Returns:
    
    AudioFormat used by this AudioContext.
  - getAudioFormat
```
public IOAudioFormat getAudioFormat(int inputs,
                                    int outputs)
```
    Generates a new AudioFormat with the same everything as the AudioContext's AudioFormat except for the number of channels.
    
    Parameters:
    
    numChannels - the number of channels.
    
    Returns:
    
    a new AudioFormat with the given number of channels, all other properties coming from the original AudioFormat.
  - defaultAudioFormat
```
public static IOAudioFormat defaultAudioFormat(int inputs,
                                               int outputs)
```
    Generates the default IOAudioFormat for AudioContext, with the given number of channels. The default values are: sampleRate=44100, sampleSizeInBits=16, signed=true, bigEndian=true.
    
    Parameters:
    
    numChannels - the number of channels to use.
    
    Returns:
    
    the generated AudioFormat.
  - postAudioFormatInfo
```
public void postAudioFormatInfo()
```
    Prints AudioFormat information to System.out.
  - printCallChain
```
public static void printCallChain(UGen current,
                                  int depth)
```
    Prints a representation of the audio signal chain stemming upwards from the specified UGen to System.out, indented by the specified depth.
    
    Parameters:
    
    current - UGen to start from.
    
    depth - depth by which to indent.
  - printCallChain
```
public void printCallChain()
```
    Prints the entire call chain to System.out (equivalent to AudioContext.printCallChain(this.out, 0);)
  - msToSamples
```
public double msToSamples(double msTime)
```
    Converts samples to milliseconds at the current sample rate.
    
    Parameters:
    
    msTime - duration in milliseconds.
    
    Returns:
    
    number of samples.
  - samplesToMs
```
public double samplesToMs(double sampleTime)
```
    Converts milliseconds to samples at the current sample rate.
    
    Parameters:
    
    sampleTime - number of samples.
    
    Returns:
    
    duration in milliseconds.
  - getTimeStep
```
public long getTimeStep()
```
    Gets the current time step of this AudioContext. The time step begins at zero when the AudioContext is started and is incremented by 1 for each update of the audio buffer.
    
    Returns:
    
    current time step.
  - generateTimeStamp
```
public TimeStamp generateTimeStamp(int index)
```
    Generates a TimeStamp with the current time step and the given index into the time step.
    
    Parameters:
    
    index - the index into the current time step.
    
    Returns:
    
    a TimeStamp.
  - getTime
```
public double getTime()
```
    Get the runtime (in ms) since starting.
  - logTime
```
public void logTime(boolean logTime)
```
    Switch on/off logging of time when running in realtime. The time is printed to System.out every 100 time steps.
    
    Parameters:
    
    logTime - set true to log time.
  - record
```
public void record(double timeMS,
                   java.lang.String filename)
            throws java.lang.Exception
```
    Tells the AudioContext to record all output for the given millisecond duration, kill the AudioContext, and save the recording to the given file path. This is a convenient way to make quick recordings, but may not suit every circumstance.
    
    Parameters:
    
    timeMS - the time in milliseconds to record for.
    
    filename - the filename to save the recording to.
    
    Throws:
    
    java.io.IOException - Signals that an I/O exception has occurred.
    
    java.lang.Exception
    
    See Also:
    
    recorder, sample
  - quickie
```
public void quickie(UGen ugen)
```
    Convenience method to quickly audition a UGen.
    
    Parameters:
    
    ugen - the UGen to audition.
  - start
```
public void start()
```
    Starts the AudioContext running in realtime. Only happens if not already running. Resets time.
  - reset
```
public void reset()
```
    Simply resets the timeStep to zero.
  - stop
```
public void stop()
```
    Stops the AudioContext if running either in realtime or non-realtime.
  - isRunning
```
public boolean isRunning()
```
    Checks if this AudioContext is running.
    
    Returns:
    
    true if running.
  - getAudioIO
```
public AudioIO getAudioIO()
```
    Returns:
    
    The AudioIO used by this context.
  - invokeAfterFrame
```
public AudioContext invokeAfterFrame(Bead target)
```
    Queues the specified Bead to be messaged upon the next audio frame completion. The Bead will be messaged only once.
    
    Parameters:
    
    target - The Bead to message.
    
    Returns:
    
    This AudioContext.
  - invokeAfterEveryFrame
```
public AudioContext invokeAfterEveryFrame(Bead target)
```
    Queues the specified Bead to be messaged after every audio frame.
    
    Parameters:
    
    target - The Bead to message.
    
    Returns:
    
    This AudioContext.
  - stopInvokingAfterEveryFrame
```
public boolean stopInvokingAfterEveryFrame(Bead target)
```
    Removes the specified Bead from the list of Beads that are messaged after every audio frame.
    
    Parameters:
    
    target - The Bead to stop messaging.
    
    Returns:
    
    Whether the Bead was being messaged.
  - invokeBeforeFrame
```
public AudioContext invokeBeforeFrame(Bead target)
```
    Queues the specified bead to be messaged before the next audio frame. The Bead will be messaged only once.
    
    Parameters:
    
    target - The Bead to message.
    
    Returns:
    
    This AudioContext.
  - invokeBeforeEveryFrame
```
public AudioContext invokeBeforeEveryFrame(Bead target)
```
    Queues the specified Bead to be messaged before every audio frame.
    
    Parameters:
    
    target - The Bead to message.
    
    Returns:
    
    This AudioContext.
  - stopInvokingBeforeEveryFrame
```
public boolean stopInvokingBeforeEveryFrame(Bead target)
```
    Removes the specified Bead from the list of Beads that are messaged before every audio frame.
    
    Parameters:
    
    target - The Bead to stop messaging.
    
    Returns:
    
    Whether the Bead was being messaged.

Class AudioContext

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_BUFFER_SIZE

out

Constructor Detail

AudioContext

AudioContext

AudioContext

AudioContext

AudioContext

Method Detail

getAudioInput

getAudioInput

update

getBuf

getCleanBuf

getZeroBuf

runNonRealTime

runForNMillisecondsNonRealTime

getBufferSize

getSampleRate

getAudioFormat

getAudioFormat

defaultAudioFormat

postAudioFormatInfo

printCallChain

printCallChain

msToSamples

samplesToMs

getTimeStep

generateTimeStamp

getTime

logTime

record

quickie

start

reset

stop

isRunning

getAudioIO

invokeAfterFrame

invokeAfterEveryFrame

stopInvokingAfterEveryFrame

invokeBeforeFrame

invokeBeforeEveryFrame

stopInvokingBeforeEveryFrame