I need to get the original width and height of an image given a specific source. My current method is:

```
img.tag = "<img style='display:none;' src='" + img.src + "' />";
img.Owidth = 0;
img.Oheight = 0;

$(img.tag).load(function() {
    img.Owidth = $(this).width();
    img.Oheight = $(this).height();
}).appendTo(img.parent());

```

With `Owidth` and `Oheight` being the original dimensions of the loaded image. I'm wondering if there is a better way to do this given that:

* The image could either already be loaded, but displayed at a different size than its original size.
* The image has not yet been loaded at all