audio-frequency-to-index

convert a Hz frequency to an index for WebAudio

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audio-frequency-to-index
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Readme

audio-frequency-to-index
stable
Convert a Hz frequency to an index for WebAudio frequency analysis. Also see audio-index-to-frequency.
The value is clamped between [ 0 .. frequencyBinCount ]. The frequencyBinCount is the same as ananlyserNode.fftSize / 2.
const freq2index = require('audio-frequency-to-index')
const sampleRate = audioContext.sampleRate // 44100
const length = analyserNode.frequencyBinCount // 1024

const index = freq2index(400, sampleRate, length)
//=> 19

Usage

NPM

index = frequencyToIndex(frequency, sampleRate, frequencyBinCount)

Converts frequency (in Hz) to an index integer using the audioContext.sampleRate and analyserNode.frequencyBinCount from the Web Audio API.

License

MIT, see LICENSE.md for details.