JSFiddle - React, Tailwind, and code Playground
by alexandroppolus
HTML
<canvas width="250" height="200" style="border:1px solid #000"></canvas>
JavaScript
var cv = document.querySelector('canvas');
var ctx = cv.getContext('2d');
ctx.fillStyle = '#ff0';
ctx.fillRect(0, 0, 100, 80);
setTimeout(function() {
var imageData = ctx.getImageData(0, 0, cv.width, cv.height);
var pix = new Uint32Array(imageData.data.buffer);
var replacedColor = 0xff00ffff;
var resultColor = 0xff1e3ce4;
console.log(pix);
for (var i = 0, n = pix.length; i < n; ++i) {
if(pix[i] == replacedColor) {
pix[i] = resultColor;
}
}
ctx.putImageData(imageData, 0, 0);
}, 2000);