Understanding AudioBuffer to ArrayBuffer conversion

amazon-web-services, express, javascript, node.js, web-audio-api

Solution

Use the copyFromChannel method, then convert the `Float32Array` to an `ArrayBuffer`.

var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);  
var anotherArray = new Float32Array();
myArrayBuffer.copyFromChannel(anotherArray,1,0);

Problem

I have an AudioBuffer client-side that I'd like to AJAX to a express server. This link shows how a XMLHttpRequest can send/receive binary data - ArrayBuffer. An ArrayBuffer is different to an AudioBuffer (or so I believe) as I decoded an ArrayBuffer to make the AudioBuffer in the first place. This was done using decodeAudioData() as part of the Web Audio API. So my question is, can I convert an AudioBuffer back to an ArrayBuffer? If this is possible, I'd like to then send the ArrayBuffer to my express server and then forward it on to a S3 bucket as shown in this example. In that example, the code PUTs a Buffer in a S3 bucket created via a fs.readFileSync(). I assume the difference between a Buffer and ArrayBuffer wont be an issue with S3 :S

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