HTML5 Image Resize

gistfile1.js

function resizeImage($img,$w,$h) {
	var maxWidth = $w;
	var maxHeight = $h;

	var w = $img.width;
	var h = $img.height;

	if(w > h) {
		if(w > maxWidth) {
			h *= maxWidth/w;
			w = maxWidth;
		}
	}
	else {
		if(h > maxHeight) {
			w *= maxHeight/h;
			h = maxHeight;
		}
	}

	// resize the image.
  	var canvas = document.createElement('canvas');
	canvas.width = w;
	canvas.height = h;

	var ctx = canvas.getContext('2d');
	ctx.drawImage($img,0,0,w,h);

	return canvas.toDataURL();
}