var i=0;
var Tab = new Array('images/light-camera-action-game-1.png', 'images/light-camera-action-game-2.png', 'images/light-camera-action-game-3.png', 'images/light-camera-action-game-4.png', 'images/light-camera-action-game-5.png');

function nextImage(){
   var x = document.getElementById('imageLeft');   
  
   if(i<Tab.length-1)
      i++;
   else
      i = 0;
   x.setAttribute("src", Tab[i]);
}

function previousImage(){
   var x = document.getElementById('imageLeft');  
   
   if(i != 0)
      i--;
   else
      i = Tab.length-1;
      
   x.setAttribute("src", Tab[i]);
}