Trait web_audio_api::context::BaseAudioContext

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pub trait BaseAudioContext {

Show 25 methods    fn base(&self) -> &ConcreteBaseAudioContext;

    fn decode_audio_data_sync<R: Read + Send + Sync + 'static>(
        &self, 
        input: R
    ) -> Result<AudioBuffer, Box<dyn Error + Send + Sync>> { ... }

    fn create_buffer(
        &self, 
        number_of_channels: usize, 
        length: usize, 
        sample_rate: SampleRate
    ) -> AudioBuffer { ... }

    fn create_analyser(&self) -> AnalyserNode { ... }

    fn create_biquad_filter(&self) -> BiquadFilterNode { ... }

    fn create_buffer_source(&self) -> AudioBufferSourceNode { ... }

    fn create_constant_source(&self) -> ConstantSourceNode { ... }

    fn create_channel_merger(&self, number_of_inputs: u32) -> ChannelMergerNode { ... }

    fn create_channel_splitter(
        &self, 
        number_of_outputs: u32
    ) -> ChannelSplitterNode { ... }

    fn create_delay(&self, max_delay_time: f64) -> DelayNode { ... }

    fn create_gain(&self) -> GainNode { ... }

    fn create_iir_filter(
        &self, 
        feedforward: Vec<f64>, 
        feedback: Vec<f64>
    ) -> IIRFilterNode { ... }

    fn create_media_stream_source<M: MediaStream>(
        &self, 
        media: M
    ) -> MediaStreamAudioSourceNode { ... }

    fn create_media_stream_destination(&self) -> MediaStreamAudioDestinationNode { ... }

    fn create_oscillator(&self) -> OscillatorNode { ... }

    fn create_panner(&self) -> PannerNode { ... }

    fn create_periodic_wave(&self, options: PeriodicWaveOptions) -> PeriodicWave { ... }

    fn create_stereo_panner(&self) -> StereoPannerNode { ... }

    fn create_wave_shaper(&self) -> WaveShaperNode { ... }

    fn create_audio_param(
        &self, 
        opts: AudioParamDescriptor, 
        dest: &AudioNodeId
    ) -> (AudioParam, AudioParamId) { ... }

    fn destination(&self) -> AudioDestinationNode { ... }

    fn listener(&self) -> AudioListener { ... }

    fn sample_rate(&self) -> f32 { ... }

    fn sample_rate_raw(&self) -> SampleRate { ... }

    fn current_time(&self) -> f64 { ... }

}
Expand description

The interface representing an audio-processing graph built from audio modules linked together, each represented by an AudioNode.

An audio context controls both the creation of the nodes it contains and the execution of the audio processing, or decoding.

Please note that in rust, we need to differentiate between the BaseAudioContext trait and the ConcreteBaseAudioContext concrete implementation.

Required methods

retrieves the ConcreteBaseAudioContext associated with this AudioContext

Provided methods

Decode an AudioBuffer from a given input stream.

The current implementation can decode FLAC, Opus, PCM, Vorbis, and Wav.

In addition to the official spec, the input parameter can be any byte stream (not just an array). This means you can decode audio data from a file, network stream, or in memory buffer, and any other std::io::Read implementor. The data if buffered internally so you should not wrap the source in a BufReader.

This function operates synchronously, which may be undesirable on the control thread. The example shows how to avoid this. An async version is currently not implemented.

Errors

This method returns an Error in various cases (IO, mime sniffing, decoding).

Example
use std::io::Cursor;
use web_audio_api::SampleRate;
use web_audio_api::context::{BaseAudioContext, OfflineAudioContext};

let input = Cursor::new(vec![0; 32]); // or a File, TcpStream, ...

let context = OfflineAudioContext::new(2, 44_100, SampleRate(44_100));
let handle = std::thread::spawn(move || context.decode_audio_data_sync(input));

// do other things

// await result from the decoder thread
let decode_buffer_result = handle.join();

Create an new “in-memory” AudioBuffer with the given number of channels, length (i.e. number of samples per channel) and sample rate.

Note: In most cases you will want the sample rate to match the current audio context sample rate.

Creates a AnalyserNode

Creates an BiquadFilterNode which implements a second order filter

Creates an AudioBufferSourceNode

Creates an ConstantSourceNode, a source representing a constant value

Creates a ChannelMergerNode

Creates a ChannelSplitterNode

Creates a DelayNode, delaying the audio signal

Creates an GainNode, to control audio volume

Creates an IirFilterNode

Arguments
  • feedforward - An array of the feedforward (numerator) coefficients for the transfer function of the IIR filter. The maximum length of this array is 20
  • feedback - An array of the feedback (denominator) coefficients for the transfer function of the IIR filter. The maximum length of this array is 20

Creates a MediaStreamAudioSourceNode from a MediaStream

Creates a MediaStreamAudioDestinationNode

Creates an OscillatorNode, a source representing a periodic waveform.

Creates a PannerNode

Creates a periodic wave

Creates an StereoPannerNode to pan a stereo output

Creates a WaveShaperNode

Create an AudioParam.

Call this inside the register closure when setting up your AudioNode

Returns an AudioDestinationNode representing the final destination of all audio in the context. It can be thought of as the audio-rendering device.

Returns the AudioListener which is used for 3D spatialization

The sample rate (in sample-frames per second) at which the AudioContext handles audio.

The raw sample rate of the AudioContext (which has more precision than the float sample_rate() value).

This is the time in seconds of the sample frame immediately following the last sample-frame in the block of audio most recently processed by the context’s rendering graph.

Implementors