mirror of
https://github.com/Tonejs/Tone.js
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31 lines
617 B
TypeScript
31 lines
617 B
TypeScript
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import { TestAudioBuffer } from "./TestAudioBuffer";
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import windowing from "fft-windowing";
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import ft from "fourier-transform";
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/**
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* Return a spectrogram of the buffer
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*/
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export function analyze(
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buffer: TestAudioBuffer,
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fftSize = 256,
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hopSize = 128
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) {
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const spectrogram: number[][] = [];
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buffer
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.toMono()
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.toArray()
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.forEach((channel) => {
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for (
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let index = 0;
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index < channel.length - fftSize;
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index += hopSize
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) {
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const segment = windowing.blackman_harris(
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channel.slice(index, index + fftSize)
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);
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spectrogram.push(ft(segment));
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}
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});
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return spectrogram;
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}
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