function preload(images) {
    if (document.images) {
        var i = 0;
        var imageArray = new Array();
        imageArray = images.split(',');
        var imageObj = new Image();
        for(i=0; i<=imageArray.length-1; i++) {
            document.write('  <img src="' + imageArray[i] + '" style="display: none;" />');// Write to page (uncomment to check images)
            imageObj.src=images[i];
        }
    }
}