net.beadsproject.beads.core
Class 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 AudioFormat used, the IO device, the audio buffer size and the system IO buffer size. An AudioContext also has provides a UGen called out, which is the output point for networks of UGens in a Beads project.

Author:

ollie

Field Summary

Gain	out The root UGen.

Constructor Summary

AudioContext()
Creates a new AudioContext with default settings.

AudioContext(int bufferSizeInFrames)
Creates a new AudioContext with default settings and the specified buffer size.

AudioContext(int bufferSizeInFrames, int systemBufferSizeInFrames)
Creates a new AudioContext with default audio format and the specified buffer size and system buffer size.

AudioContext(int bufferSizeInFrames, int systemBufferSizeInFrames, javax.sound.sampled.AudioFormat audioFormat)
Creates a new AudioContext with the specified buffer size, system buffer size and audio format.

Method Summary

void	checkForDroppedFrames(boolean checkForDroppedFrames) Switch on/off checking for dropped frames when running in realtime.
void	chooseMixerCommandLine() Presents a choice of mixers on the commandline.
javax.sound.sampled.AudioFormat	getAudioFormat() Gets the AudioFormat for this AudioContext.
int	getBufferSize() Gets the buffer size for this AudioContext.
float	getSampleRate() Gets the sample rate for this AudioContext.
int	getTimeStep() Gets the current time step of this AudioContext.
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	postSourceDataLineInfo() Prints SourceDataLine info to System.out.
static void	printMixerInfo() Prints information about the current Mixer to System.out.
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 and save the recording to the given file path.
void	runNonRealTime() Starts the AudioContext running in non-realtime.
double	samplesToMs(double sampleTime) Converts milliseconds to samples at the current sample rate.
void	selectMixer(int i) Select a mixer by index.
void	start() Starts the AudioContext running in realtime.
void	stop() Stops the AudioContext if running either in realtime or non-realtime.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

out

public final Gain out

The root UGen.

Constructor Detail

AudioContext

public AudioContext()

Creates a new AudioContext with default settings. The default buffer size is 512 and the default system buffer size is 5000. The default audio format is 44.1Khz, 16 bit, stereo, signed, bigEndian.

AudioContext

public AudioContext(int bufferSizeInFrames)

Creates a new AudioContext with default settings and the specified buffer size. The default system buffer size is determined by the JVM. The default audio format is 44.1Khz, 16 bit, stereo, signed, bigEndian.

Parameters:

bufferSizeInFrames - the buffer size in samples.

AudioContext

public AudioContext(int bufferSizeInFrames,
                    int systemBufferSizeInFrames)

Creates a new AudioContext with default audio format and the specified buffer size and system buffer size. The default audio format is 44.1Khz, 16 bit, stereo, signed, bigEndian.

Parameters:

bufferSizeInFrames - the buffer size in samples.

systemBufferSizeInFrames - the system buffer size in samples.

AudioContext

public AudioContext(int bufferSizeInFrames,
                    int systemBufferSizeInFrames,
                    javax.sound.sampled.AudioFormat audioFormat)

Creates a new AudioContext with the specified buffer size, system buffer size and audio format.

Parameters:

bufferSizeInFrames - the buffer size in samples.

systemBufferSizeInFrames - the system buffer size in samples.

audioFormat - the audio format, which specifies sample rate, bit depth, number of channels, signedness and byte order.

Method Detail

chooseMixerCommandLine

public void chooseMixerCommandLine()

Presents a choice of mixers on the commandline.

selectMixer

public void selectMixer(int i)

Select a mixer by index.

Parameters:

i - the index of the selected mixer.

printMixerInfo

public static void printMixerInfo()

Prints information about the current Mixer to System.out.

isRunning

public boolean isRunning()

Checks if this AudioContext is running.

Returns:

true if running.

start

public void start()

Starts the AudioContext running in realtime.

runNonRealTime

public void runNonRealTime()

Starts the AudioContext running in non-realtime. This occurs in the current Thread.

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 javax.sound.sampled.AudioFormat getAudioFormat()

Gets the AudioFormat for this AudioContext.

Returns:

AudioFormat used by this AudioContext.

stop

public void stop()

Stops the AudioContext if running either in realtime or non-realtime.

postAudioFormatInfo

public void postAudioFormatInfo()

Prints AudioFormat information to System.out.

postSourceDataLineInfo

public void postSourceDataLineInfo()

Prints SourceDataLine info to System.out.

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 int 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.

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.

checkForDroppedFrames

public void checkForDroppedFrames(boolean checkForDroppedFrames)

Switch on/off checking for dropped frames when running in realtime. The scheduler checks to see if audio is not being calculated quickly enough, and prints dropped-frame messages to System.out.

Parameters:

checkForDroppedFrames - set true to check for dropped frames.

record

public void record(double timeMS,
                   java.lang.String filename)
            throws java.io.IOException

Tells the AudioContext to record all output for the given millisecond duration 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.

See Also:

Recorder, Sample}

quickie

public void quickie(UGen ugen)

Convenience method to quickly audition a UGen.

Parameters:

ugen - the UGen to audition.