var objCount = 0; // number of (changing) images on web-page
function preload(name, first, second) {  
if (browserOK) {     
pics[objCount] = new Array(25);
pics[objCount][0] = new Image();
pics[objCount][0].src = first;
pics[objCount][1] = new Image();
pics[objCount][1].src = second;
pics[objCount][2] = name;
objCount++;
}
}
function on(name){
if (browserOK) {
for (i = 0; i < objCount; i++) {
if (document.images[pics[i][2]] != null)
if (name != pics[i][2]) { 
// set back all other pictures
document.images[pics[i][2]].src = pics[i][0].src;
} else {
// show the second image because cursor moves across this image
document.images[pics[i][2]].src = pics[i][1].src;
}
}
}
}
function off(){
if (browserOK) {
for (i = 0; i < objCount; i++) {
// set back all pictures
if (document.images[pics[i][2]] != null) 
document.images[pics[i][2]].src = pics[i][0].src;
}
}
}
preload("images/indexbg_01.jpg");
preload("link1","images/indexbg_01aa.jpg" , "images/indexbg_01ab.jpg");
preload("link2","images/indexbg_01ba.jpg" , "images/indexbg_01bb.jpg");
preload("link3","images/indexbg_01ca.jpg" , "images/indexbg_01cb.jpg");
preload("link4","images/indexbg_01da.jpg" , "images/indexbg_01db.jpg");