Package com.codename1.media.audio

package com.codename1.media.audio

A real-time and offline audio graph modelled on the W3C Web Audio API.

Sources (AudioBufferSourceNode, OscillatorNode, ConstantSourceNode) feed processing nodes (GainNode, DelayNode, BiquadFilterNode, IIRFilterNode, StereoPannerNode, ChannelSplitterNode, ChannelMergerNode) that end at the context's destination. Node parameters are AudioParams with sample-accurate automation and can be modulated by other nodes.

ConvolverNode (reverb), DynamicsCompressorNode, WaveShaperNode (distortion) and AnalyserNode (spectrum and waveform for visualisers) complete the processing set.

PannerNode places a source in 3D around the context's AudioListener, with the specification's distance models and sound cones. Its PanningModel.HRTF mode renders binaurally for headphones from a structural head model (interaural delay, head shadow and pinna echoes), so it is the same portable code, with the same result, on every platform.

OfflineAudioContext renders to memory on every platform. AudioContext plays to the speaker where the platform has a real-time output; call AudioContext.isSupported() first. Names and behaviour follow the specification, so Web Audio material applies with Java naming: gain.gain.value = 0.5 becomes gain.getGain().setValue(0.5f).

The graph is rendered by portable code, so a graph sounds the same on every platform it runs on.

Related Packages

Package	Description
com.codename1.media	Video and Audio playback support are handled within this package using the com.codename1.media.Media & com.codename1.media.MediaManager APIs.

Class	Description
AnalyserNode	Exposes the recent signal and its spectrum for visualisation, passing its input through unchanged: the Web Audio AnalyserNode.
AudioBufferSourceNode	Plays AudioData, the Web Audio AudioBufferSourceNode.
AudioContext	Renders an audio graph to the device's speaker in real time, the Web Audio AudioContext.
AudioContextState	The life cycle state of an audio context.
AudioData	In-memory PCM audio: one float array per channel, samples nominally in the range -1 to 1.
AudioDestinationNode	The end of every audio graph: the speaker for an AudioContext, the rendered AudioData for an OfflineAudioContext.
AudioListener	The position and orientation of the listener every PannerNode of a context is heard from, the Web Audio AudioListener.
AudioNode	A processing block of an audio graph, the Web Audio AudioNode.
AudioOutputPeer	A platform audio output stream that pulls samples from an AudioRenderCallback.
AudioParam	A value of an AudioNode that can be scheduled ahead of time and modulated by other nodes, the Web Audio AudioParam.
AudioParamDescriptor	Declares one AudioParam of an AudioProcessorNode, the Web Audio AudioParamDescriptor.
AudioProcessor	Custom DSP in Java, the Codename One counterpart of the Web Audio AudioWorkletProcessor.
AudioProcessorNode	Runs an AudioProcessor in the graph, the Web Audio AudioWorkletNode.
AudioRenderCallback	Supplies the samples an AudioOutputPeer plays.
AudioScheduledSourceNode	A source node that is started and stopped at scheduled times, the Web Audio AudioScheduledSourceNode.
AutomationRate	Whether an AudioParam is computed for every sample or once per render quantum.
BaseAudioContext	What AudioContext (real time, to the speaker) and OfflineAudioContext (as fast as possible, to memory) share: the clock, the destination and the factory methods for every node, the Web Audio BaseAudioContext.
BiquadFilterNode	A second order filter, the Web Audio BiquadFilterNode: low and high pass, band pass, shelves, peaking, notch and all pass.
BiquadFilterType	The response of a BiquadFilterNode.
ChannelCountMode	How an AudioNode decides the number of channels it mixes its inputs to, matching the Web Audio ChannelCountMode enumeration.
ChannelInterpretation	How channels are up-mixed or down-mixed when a connection has a different number of channels than the input it feeds, matching the Web Audio ChannelInterpretation enumeration.
ChannelMergerNode	Merges mono inputs into one output with a channel per input, the Web Audio ChannelMergerNode.
ChannelSplitterNode	Splits the channels of its input into mono outputs, the Web Audio ChannelSplitterNode.
ConstantSourceNode	A mono source whose output is ConstantSourceNode.getOffset(), the Web Audio ConstantSourceNode.
ConvolverNode	Convolves its input with an impulse response, for reverb and cabinet or room simulation: the Web Audio ConvolverNode.
DelayNode	Delays its input by DelayNode.getDelayTime(), the Web Audio DelayNode.
DistanceModelType	How a PannerNode attenuates a source with distance, using its refDistance, maxDistance and rolloffFactor.
DynamicsCompressorNode	Lowers the volume of loud passages so the mix stays clear of clipping: the Web Audio DynamicsCompressorNode.
GainNode	Multiplies its input by GainNode.getGain(), the Web Audio GainNode.
IIRFilterNode	A general infinite impulse response filter with fixed coefficients, the Web Audio IIRFilterNode.
MicrophoneSourceNode	Live captured audio as a graph source, the Codename One counterpart of the Web Audio MediaStreamAudioSourceNode for a microphone.
OfflineAudioContext	Renders an audio graph to memory as fast as the device can, the Web Audio OfflineAudioContext.
OscillatorNode	A band-limited periodic waveform, the Web Audio OscillatorNode.
OscillatorType	The waveform an OscillatorNode generates.
OverSampleType	How much a WaveShaperNode oversamples while it applies its curve: the Web Audio "none", "2x" and "4x".
PannerNode	Positions a source in 3D space relative to the context's AudioListener, the Web Audio PannerNode.
PanningModel	How a PannerNode places a source in the stereo output.
PeriodicWave	A custom oscillator waveform given by its Fourier coefficients, the Web Audio PeriodicWave.
StereoPannerNode	Places mono or stereo input in the stereo field with an equal-power law, the Web Audio StereoPannerNode.
WaveShaperNode	Applies a transfer curve to every sample, for distortion and saturation: the Web Audio WaveShaperNode.