Class: instance

VowelWorm. 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





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



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


The size of the FFT, in bins

getFormants(data, sampleRate){Array.<number>}

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


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


The sample rate of the attached audio source


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