jQuery fadeout image
<p>I have a code to change image for every fixed intervals but this image is just normally changing. How can I use fadeout option to my code so that it will slowly fadeout to open a new image. My code follows</p>

<pre><code>$(document).ready(function() {
        (function() {
            var curImgId = 0;
            var numberOfImages = 2;
            window.setInterval(function() {
                $('body').css('background-image','url(bg' + curImgId + '.jpg)');
                curImgId = (curImgId + 1) % numberOfImages;
            }, 15 * 100);
        })();
 });
</code></pre>
