var currentPic=1;

	var IE4 = (document.all && !document.getElementById) ? true : false;
	var NS4 = (document.layers) ? true : false;
	var IE5 = (document.all && document.getElementById) ? true : false;
	var N6 = (document.getElementById && !document.all) ? true : false;

 
	var extension = '.jpg';

	
	function buildImageName(imgFolder,basename)
	{
	    var nb="00";
	    
	    if (NS4 || IE4)
	     nb= eval(""+currentPic);
	    else 
	     nb= ""+currentPic;

	    
	    //PADDING A 2 zeros
	    if (nb.length <2)
	     if (NS4 || IE4)
	     nb= eval("0"+nb);
	    else 
	     nb= "0"+nb;
	     
     
	    var name ="";
	     if (NS4 || IE4)
	     name = eval(imgFolder+"/"+basename+nb+extension);
	    else
	        name = imgFolder+"/"+basename+nb+extension;
	    return name;
	}
	
	function updateCounter(nbPics)
	{
		var divTxt = getEl('slidepos');
		divTxt.innerHTML = currentPic+"/"+nbPics;
	}
		
	function firstPic(imgFolder, basename, nbPics)
	{
		currentPic=1;
		setSrc('slidepic',buildImageName(imgFolder,basename));
		updateCounter(nbPics);
	} 

	function lastPic(imgFolder, basename, nbPics)
	{
		currentPic=nbPics;
		setSrc('slidepic',buildImageName(imgFolder,basename));
		updateCounter(nbPics);
	} 

		
	function prevPic(imgFolder, basename, nbPics)
	{
		currentPic--;
		
		if (currentPic<1)
		currentPic=nbPics;

		setSrc('slidepic',buildImageName(imgFolder,basename));
		updateCounter(nbPics);
	}
	
	function nextPic(imgFolder, basename, nbPics)
	{
		currentPic++;
		
		if (currentPic >nbPics)
		currentPic=1;

		setSrc('slidepic',buildImageName(imgFolder,basename));
		updateCounter(nbPics);
	} 

        function getEl(id)
        {
        	var item;
        	
	          if (NS4) { item = eval("document." + id);}
		  else if (IE4) { item = eval("document.all." + id);}
		       else if (IE5 || N6) {
		       item = document.getElementById(id);
		       }
	       
	       return item;
        }		
		
	function setSrc(id, url) 
	{
	    var item = getEl(id);
	    item.src = url;
	}