Vanilagy

const RGBAToYUV420 = ({ width, height, data }: ImageData) => {
    // Assume both width and height are even
	let yuv = new Uint8Array(width * height * 1.5);

    // Use loop tiling as a cache optimization
	const tileSize = 64;
	for (let y0 = 0; y0 < height; y0 += tileSize) {
		for (let x0 = 0; x0 < width; x0 += tileSize) {
			let limitX = Math.min(width, x0 + tileSize);
			let limitY = Math.min(height, y0 + tileSize);

Vanilagy

// @Vanilagy 2019
//
// Example: 
// structuredClone([5, {hello: 'world'}, new Set()]).then((data) => console.log(data));
// > [5, {hello: "world"}, Set(0)]

var structuredClone = (function() {
    var sender = new BroadcastChannel('structuredClone'),
        receiver = new BroadcastChannel('structuredClone');