How to get image size (height & width) using JavaScript?

Question

Are there any JavaScript or jQuery APIs or methods to get the dimensions of an image on the page?

Answer 1

Nicky De Maeyer asked after a background picture; I simply get it from the css and replace the "url()":

var div = $('#my-bg-div');
var url = div.css('background-image').replace(/^url\(\'?(.*)\'?\)$/, '$1');
var img = new Image();
img.src = url;
console.log('img:', img.width + 'x' + img.height); // zero, image not yet loaded
console.log('div:', div.width() + 'x' + div.height());
img.onload = function() {
  console.log('img:', img.width + 'x' + img.height, (img.width/div.width()));
}