var nazi = new Image;
nazi.src = "http://cdn.thedailybeast.com/content/dailybeast/articles/2016/05/26/how-pepe-the-frog-became-a-nazi-trump-supporter-and-alt-right-symbol/jcr:content/image.img.2000.jpg/1464239062807.cached.jpg";
nazi.crossOrigin="anonymous";
var myCanvas = document.getElementById('sketch');
var ctx = myCanvas.getContext('2d');
nazi.onload = function(){
  ctx.drawImage(nazi,20,20,610,435); // Or at whatever offset you like
};