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Spectrum - Dots

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Aalexmacy
Last edited Jun 29, 2017
Created on Jun 29, 2017

A real-time audio spectrum analyzer renders live microphone input as a field of dots on a canvas. Each dot represents a frequency bin, with its vertical position mapped to amplitude via d3.scaleLinear and its color transitioning from white to red based on intensity. The visualization uses the Web Audio API’s AnalyserNode to capture frequency data, while d3.js scales the x and y coordinates. Animation runs continuously through requestAnimationFrame, drawing translucent overlays to create a fading trail effect.

AI-generated description

A relatively simple audio spectrum analyzer built using the <a href="https://developer.mozilla.org/en-US/docs/Web/API/Web_Audio_API" target="_blank">Web Audio API</a> and <a href="https://d3js.org/" target="_blank">d3.js</a> and rendered using canvas. Also made a dark version: <a href='http://bl.ocks.org/alexmacy/52e607ddddad95e5653a0a96681aabaa'>Audio Spectrum Analyzer - dark</a>

This was made as part of a series exploring the visualization of audio that was presented at a d3.oakland meetup. A big list of the demos from this series can be found <a href="https://alexmacy.github.io/d3.oakland" target="_blank">here</a>.

mit Licensed

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