function getTopPos(inputObj)
{
    var returnValue = inputObj.offsetTop;
    while((inputObj = inputObj.offsetParent) != null){returnValue += inputObj.offsetTop;}
    return returnValue;
 }

function getLeftPos(inputObj)
{
    var returnValue = inputObj.offsetLeft;
    while((inputObj = inputObj.offsetParent) != null){returnValue += inputObj.offsetLeft;}
    return returnValue;
 }

function show_large_image(obj)
{
    var large_image_obj = document.getElementById("image_holder");
    large_image_obj.src = obj.src;
    large_image_obj.style.left = getLeftPos(obj)+"px";
    large_image_obj.style.top = getTopPos(obj)+"px";
    large_image_obj.style.display = "block";
 }

function hide_large_image(obj)
{
    obj.style.display = "none";
}