Converts all images on a page to canvas of images

img2canvas.js

// requires jQuery obviously

$(function(){
  $('img').each(function(i, img){
    var $img = $(img);
    var url = $img.attr('src');
    var w = $img.width();
    var h = $img.height();
    var canvas = $('<canvas data-image="'+i+'"></canvas>').attr({ width: w, height: h });
    $(img).replaceWith(canvas);
    
    canvas = $('canvas[data-image="'+i+'"]')[0];
    var context = canvas.getContext('2d');
    var imageObj = new Image();
    
    imageObj.onload = function() {
      context.drawImage(imageObj, 0, 0, w, h);
    };
    imageObj.src = url;
  });
});