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] + '" />');// Write to page (uncomment to check images)
            imageObj.src=images[i];
        }
    }
}

function changeOpac(opacity) {
  var object = document.getElementById('menu-i').style;
  object.opacity = (opacity / 100);
  object.MozOpacity = (opacity / 100);
  object.KhtmlOpacity = (opacity / 100);
  object.filter = "alpha(opacity=" + opacity + ")";
}

function menuimage(page, title) { 
    var speed = 5; 
    var timer = 0;
    var imagefile = "img/m_" + page + ".jpg";
    var imagelink = page + ".php";
     
    //set the current image as background 
    document.getElementById('menu-d').style.backgroundImage = "url(" + document.getElementById('menu-i').src + ")"; 
     
    //make image transparent 
    changeOpac(0); 
     
    //make new image 
    document.getElementById('menu-i').src = imagefile;
    document.getElementById('menu-i').alt = title;
    document.getElementById('menu-i').title = title;
    
    //change title text
    document.getElementById('menu-t').innerHTML = title;
    
    //change href
    document.getElementById('menu-l').href = imagelink;
    
    //fade in image 
    for(i = 0; i <= 100; i++) { 
        setTimeout("changeOpac(" + i + ",'menu-i')",(timer * speed)); 
        timer++; 
    } 
}