// JavaScript Document

function showPreviewPic(picPath, opacStart, opacEnd, millisec) { 
    //speed for each frame 
    var speed = Math.round(millisec / 100); 
    var timer = 0; 
	var obj = document.getElementById('previewImg');

    //determine the direction for the blending, if start and end are the same nothing happens
	obj.style.opacity = 0;
	obj.style.MozOpacity = 0; 
	obj.style.KhtmlOpacity = 0; 
	obj.style.filter = "alpha(opacity= "+ 0 +")";
	obj.src = picPath;
	
	if(opacStart < opacEnd) { 
		for(i = opacStart; i <= opacEnd; i++) 
			{
			setTimeout("changeOpac(" + i + ", 'previewImg')",(timer * speed)); 
			timer++; 
			 
		}
	}
}


//change the opacity for different browsers 
function changeOpac(opacity, obj) {
	var object = document.getElementById(obj).style;
    object.opacity = (opacity / 100); 
    object.MozOpacity = (opacity / 100); 
    object.KhtmlOpacity = (opacity / 100); 
    object.filter = "alpha(opacity=" + opacity + ")"; 
}