How to check if image exists with given url?

I want to check if an image exists using jquery.

For example how do I check this image exists

http://www.google.com/images/srpr/nav_logo14.png 

the check must give me a 200 or status ok

--------------edited-------------------

var imgsrc = $(this).attr('src');
var imgcheck = imgsrc.width;


if (imgcheck==0) {
alert("You have a zero size image");
} else { //do rest of code }

Thanks Jean