I have a Float32Array with values from an audio file.I want to save it as a .wav file so I need to convert that values to a Uint8array.
To convert from uint8 to float I convert first to an int16 array and then to a Float32Array (Convert int16 array to float) How can I do that conversion in the other direction?
You can convert to an ArrayBuffer, copy the data into and then create a byte view of this buffer :
var data = new Float32Array([0.1, 0.2, 0.3]);
var buffer = new ArrayBuffer(data.byteLength);
var floatView = new Float32Array(buffer).set(data);
var byteView = new Uint8Array(buffer);
This function can convert any TypedArray to any other kind of TypedArray :
function convertTypedArray(src, type) {
var buffer = new ArrayBuffer(src.byteLength);
var baseView = new src.constructor(buffer).set(src);
return new type(buffer);
}
Example :
convertTypedArray(new Float32Array([0.5, 0.3, -0.1]), Uint8Array);
As Ian pointed out in the comment section, you can access the ArrayBuffer with TypedArray.buffer, so you can simply do :
var byteArray = new Uint8Array(floatArray.buffer);
Note that doing this, byteArray and floatArray will share the same buffer, so modifying byteArray will modify floatArray and vice versa.
return new type(src.buffer).
const floats = new Float32Array([1.53, 1000.5]), using new Uint8Array(floats) will give you [1, 232], so be careful. Only in certain circumstances will you want your floats to be wrap back around 255. i.e. 232 was gotten by doing 1000-256-256-256