A function that fit images to his parent

fitImages.css

body img{
	width: 100%; /* default */
}
img.fitWidth{
	height: 100% !important;
	width: auto !important; 
}

fitImages.js

fitImages: function(){
		var screenImages = $("body img"); //select the img of the screen
		
		$.each(screenImages, function(i, item) {
			var theImage = new Image(); // Create new offscreen image to test
			theImage.src = $(item).attr("src");
			// Get accurate measurements from that.
			theImage.onload = function() { //it will be 0x0 if you don't try to get the dimensions on the load
				var imageWidth = this.width;
				var imageHeight = this.height;
				if (imageWidth > imageHeight)
					$(item).addClass('fitWidth'); //check fitImages.css
			}
		});
	}