Because of security restrictions, getImageFromUrl will not load images from other domains.  Chrome has added security restrictions that prevent it from loading images when running local files.  Run with: chromium --allow-file-access-from-files --allow-file-access to temporarily get around this issue.
function (url, callback) {
		var img = new Image(), data, ret = {
			data: null,
			pending: true
		};

		img.onError = function () {
			throw new Error('Cannot load image: "' + url + '"');
		};
		img.onload = function () {
			var canvas = document.createElement('canvas');
			document.body.appendChild(canvas);
			canvas.width = img.width;
			canvas.height = img.height;

			var ctx = canvas.getContext('2d');
			ctx.drawImage(img, 0, 0);
			// Grab the image as a jpeg encoded in base64, but only the data
			data = canvas.toDataURL('image/jpeg').slice('data:image/jpeg;base64,'.length);
			// Convert the data to binary form
			data = atob(data);
			document.body.removeChild(canvas);

			ret['data'] = data;
			ret['pending'] = false;
			if (typeof callback === 'function') {
				callback(data);
			}
		};
		img.src = url;

		return ret;
	}