function next_image() 
{
  count++;
  if( count > max ) count = 0;
  document.display_img.src = dir_path + "/" + files[count];
  document.getElementById('link_img').href = dir_path + "/" + files[count];
}
 
function previous_image() 
{
  count--;
  if( count < 0 ) count = max;
  document.display_img.src = dir_path + "/" + files[count];
  document.getElementById('link_img').href = dir_path + "/" + files[count];
}

function display_image(count)
{
  document.display_img.src = dir_path + "/" + files[count];
  document.getElementById('link_img').href = dir_path + "/" + files[count];
}
  
function enlarge_image(item)
{
  document.getElementById(item.name).style.zIndex = "10";
  item.height = "100";
}

function reduce_image(item)
{
  document.getElementById(item.name).style.zIndex = "0";
  item.height = "80";
}

function btn_over(id)
{
  if( id == "pre_id" )
  {
    document.getElementById(id).src = previous_over_icon;
  }
  else
  {
    document.getElementById(id).src = next_over_icon;
  }
}

function btn_out(id)
{
  if( id == "pre_id" )
  {
    document.getElementById(id).src = previous_icon;
  }
  else
  {
    document.getElementById(id).src = next_icon;
  }
}

function submit_folder(folder)
{
  document.getElementById("hdn_folder").value = folder;
  document.folder_form.submit();
}

function folder_over(folder)
{
  document.getElementById("div_"+folder).className = "alpha";
  document.getElementById("txt_"+folder).style.color = "#f00";
  
  //folder.style.borderColor = "#f00";
  //folder.style.color = "#f00";
}

function folder_out(folder)
{
  document.getElementById("div_"+folder).className = "";
  document.getElementById("txt_"+folder).style.color = "#fff";
  
  //folder.style.borderColor = "#fff";
  //folder.style.color = "#fff";
}

function play_track(track)
{
  document.getElementById("hdn_track").value = track;
  document.folder_form.submit();
}