Run results for: Canvas context2d: Image vs ImageBitmap vs Canvas (with clear canvas and alpha true)

Test name	Executions per second
✓ Canvas	1,147,358 Ops/sec
Image	1,049,807 Ops/sec
ImageBitmap	967,186 Ops/sec

Script Preparation code:

var img = new Image();
var imageBitmap;
var doneLoading = false;
var canvasImage = document.createElement('canvas');
canvasImage.width = 700;
canvasImage.height = 700;
var canvasImageBitmap = document.createElement('canvas');
canvasImageBitmap.width = 700;
canvasImageBitmap.height = 700;
var canvas = document.createElement('canvas');
canvas.width = 700;
canvas.height = 700;
var canvasCanvas = document.createElement('canvas');
canvasCanvas.width = 700;
canvasCanvas.height = 700;

var ctxImage = canvasImage.getContext('2d');
var ctxImageBitmap = canvasImageBitmap.getContext('2d');
var ctx = canvas.getContext('2d');
var ctxCanvas = canvasCanvas.getContext('2d');

async function globalMeasureThatScriptPrepareFunction() {
  return new Promise((resolve, reject) => {
    img.addEventListener('load', function() {
        createImageBitmap(img)
      .then(function(bitmap) {
        imageBitmap = bitmap;
        debugger;
        doneLoading = true;
        console.log("bitmap preparation done");
        resolve(true);
      }, false);
      
      ctx.drawImage(img, 0, 0);
      console.log("canvas preparation done");
    });

    img.src = 'https://1.bp.blogspot.com/-52MtzD0GfX0/WvP52CL1WjI/AAAAAAAAOVw/_OpK4JHeWK01d-7IiZ6vzojYGhXqLRXrACLcBGAs/s1600/EMxediL.jpg';
  });
}

Tests:

Image
ctxImage.drawImage(img,0,0); ctxImage.clearRect(0,0,700,700);
ImageBitmap
ctxImageBitmap.drawImage(imageBitmap,0,0); ctxImageBitmap.clearRect(0,0,700,700);
Canvas
ctxCanvas.drawImage(canvas,0,0); ctxCanvas.clearRect(0,0,700,700);