var Down=2;

var MediaItems=new Array();

function GetMediaItems()
{
var j=0;
MediaItems=[];
for(i=0;i<document.getElementsByTagName("input").length;i++)            
    if(document.getElementsByTagName("input").item(i).type=="image" && document.getElementsByTagName("input").item(i).className=="MediaListItems")
    {        
        MediaItems[j]=document.getElementsByTagName("input").item(i).id;                
        j++;                            
    }          
}

function SlideUp()
{
    GetMediaItems();    
                      
        if(Down < MediaItems.length-1) 
        {
            
            document.getElementById(MediaItems[Down-2]).style.visibility = "hidden";
            document.getElementById(MediaItems[Down-2]).style.display = "none";            
            document.getElementById(MediaItems[Down+1]).style.visibility = "visible";
            document.getElementById(MediaItems[Down+1]).style.display = "block";
            
            Down+=1;            
            
            for(i=0;i<MediaItems.length;i++)            
                if(i<Down-2 && i>Down)
                    document.getElementByID(MediaItems[i]).style.visibility = "hidden";
         }
}
function SlideDown()
{
        GetMediaItems();
        
        if(Down-2>0) {            
            document.getElementById(MediaItems[Down]).style.visibility = "hidden";
            document.getElementById(MediaItems[Down]).style.display = "none";            
            document.getElementById(MediaItems[Down-3]).style.visibility = "visible";
            document.getElementById(MediaItems[Down-3]).style.display = "block";                                                                                
            
            Down-=1;            
            
            for(i=0;i<MediaItems.length;i++)            
                if(i<Down-2 && i>Down)
                    document.getElementByID(MediaItems[i]).style.visibility = "hidden";
         }
}