var bgimgurl = ["_images/homepage-loop1.jpg", "_images/homepage-loop2.jpg", "_images/homepage-loop3.jpg", "_images/homepage-loop4.jpg", "_images/homepage-loop5.jpg", "_images/homepage-loop6.jpg", "_images/homepage-loop7.jpg", "_images/homepage-loop8.jpg"]; // images
var maskurl = ["_images/mask00.png", "_images/mask10.png", "_images/mask20.png", "_images/mask30.png", "_images/mask40.png", "_images/mask50.png", "_images/mask60.png", "_images/mask70.png", "_images/mask80.png", "_images/mask90.png", "_images/mask100.png"]; // mask images

// preload images
var bgimg = []; 
for(i=0; i<bgimgurl.length; i++){
  bgimg[i] = new Image();
  bgimg[i].src = strPath + bgimgurl[i];
}

// preload masks
var mask = []; 
for(i=0; i<maskurl.length; i++){
  mask[i] = new Image();
  mask[i].src = strPath + maskurl[i];
}

var maskDuration = 75;
var totalDuration = 5000;
var staticDuration = totalDuration - 2*maskDuration*(mask.length-1);
var strMethod = "standard";

function getMethod() {
  var arVersion = navigator.appVersion.split("MSIE");
  var version = parseFloat(arVersion[1]);
  if ((version >= 5.5) && (version < 7) && (document.body.filters)) {
    strMethod = "filter";
    document.getElementById("imMask").style.display = "none";
  } else {
    document.getElementById("spMask").style.display = "none";
  }
}

function changePic() {

   document.getElementById('bannerphoto').style.background = "url(" + bgimg[j].src + ") -1px top no-repeat"; //change background 

   if (strMethod == "filter") {
     for (i=1; i<mask.length; i++) {   //1 to 5
       setTimeout("document.getElementById('spMask').style.filter = \"progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + mask[mask.length-1-i].src + "', sizingMethod='scale')\"", maskDuration*i);   //4 to 0, 1 to 5
     }

     for (i=1; i<mask.length; i++) {  //1 to 5
       setTimeout("document.getElementById('spMask').style.filter = \"progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + mask[i].src + "', sizingMethod='scale')\"", staticDuration + maskDuration*(mask.length+i-2));   //1 to 5, static + (5 to 9)
     }
   } else {
     document.getElementById('imMask').src = mask[mask.length-1].src;  //initialise mask

     for (i=1; i<mask.length; i++) {   //1 to 5
       setTimeout("document.getElementById('imMask').src = mask[" + (mask.length-1-i) + "].src", maskDuration*i);   //4 to 0, 1 to 5
     }

     for (i=1; i<mask.length; i++) {  //1 to 5
       setTimeout("document.getElementById('imMask').src = mask[" + i + "].src", staticDuration + maskDuration*(mask.length+i-2));   //1 to 5, static + (5 to 9)
     }
   }
 
   j = j + 1;
   if (j >= bgimgurl.length) {j = 0};
}