<!DOCTYPE html> <head><meta charset="utf-8"></head> <body> <canvas id="canvas" width="200" height="200"></canvas> <script> let canvas = document.getElementById('canvas'); let ctx = canvas.getContext('2d'); let arr = new Uint8ClampedArray(Array(40000).fill(200)); createImageBitmap(new ImageData(arr, 100)).then(img => { for (let i=0; i<100; i+=50) ctx.drawImage(img, i, i); }); </script> </body>