Class: instance

new VowelWorm.instance(stream)

Contains methods used in the analysis of vowel audio data

Name	Type	Description
`stream`	*	The audio stream to analyze OR a string representing the URL for an audio file

Namespaces

draw

Members

nullablemodenumber

The current mode the vowel worm is in (e.g., stream, audio element, etc.)

See:

Methods

destroy() vowelworm.js, line 1092

Removes reference to this particular worm instance as well as all properties of it.

getFFT() vowelworm.js, line 770

Retrieves the current FFT data of the audio source. NOTE: this returns a reference to the internal buffer used to store this information. It WILL change. If you need to store it, iterate through it and make a copy. The reason this doesn't return a new Float32Array is because Google Chrome (as of v. 36) does not adequately garbage collect new Float32Arrays. Best to keep them to a minimum.

Example

var w = new VowelWorm.instance(audioelement),
    fft = w.getFFT();

// store a copy for later
var saved_data = [];
for(var i = 0; i<fft.length; i++) {
  saved_data[i] = fft[i];
}

getFFTSize(){number} vowelworm.js, line 902

The size of the FFT, in bins

getFormants(data, sampleRate){Array.<number>} vowelworm.js, line 1050

Retrieves formants. Uses the current time of the audio file or stream, unless data is passed in.

Name	Type	Description
`data`	Array.<number>	optional FFT transformation data. If null, pulls from the analyzer
`sampleRate`	number	optional the sample rate of the data. Required if data is not null

Returns:

formants found for the audio stream/file. If nothing worthwhile has been found, returns an empty array.

getMFCCs(options){Array.<number>} vowelworm.js, line 943

Retrieves Mel Frequency Cepstrum Coefficients (MFCCs). For best results, if using preexisting webaudio FFT data (from getFloatFrequencyData), pass your values through VowelWorm.decibelsToLinear first. If you do not pass in specific FFT data, the default data will be converted to a linear magnitude scale anyway.

Name	Type	Description
`options`	Object	mfccsOptions

Returns:

MFFCs. Probably relevant are the second and third values (i.e., a[1] and a[2])

getSampleRate(){number} vowelworm.js, line 880

The sample rate of the attached audio source

setStream(stream) vowelworm.js, line 790

Specifies the audio source for the instance. Can be a video or audio element, a URL, or a MediaStream

Name	Type	Description
`stream`	MediaStream \| string \| HTMLAudioElement \| HTMLVideoElement	The audio stream to analyze OR a string representing the URL for an audio file OR an Audio file

Throws:

An error if stream is neither a Mediastream, Audio or Video Element, or a string