/* fade-in fade-out */

function opacity(id, opacStart, opacEnd, millisec) { 
    //speed for each frame 
    var speed = Math.round(millisec / 100); 
    var timer = 0; 

    //determine the direction for the blending, if start and end are the same nothing happens 
    if(opacStart > opacEnd) { 
        for(i = opacStart; i >= opacEnd; i--) { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } else if(opacStart < opacEnd) { 
        for(i = opacStart; i <= opacEnd; i++) 
            { 
            setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed)); 
            timer++; 
        } 
    } 
} 

function shiftOpacity(id, millisec) { 
    //if an element is invisible, make it visible, else make it ivisible 
    if(document.getElementById(id).style.opacity == 0) { 
        opacity(id, 0, 100, millisec); 
    } else { 
        opacity(id, 100, 0, millisec); 
    } 
} 

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

function blendimage(divid, imageid, imageNewSrc, millisec) { 
    var speed = Math.round(millisec / 100); 
    var timer = 0; 
    //set the current image as background 
    document.getElementById(divid).style.backgroundImage = "url(" + document.getElementById(imageid).src + ")"; 
     
    //make image transparent 
    changeOpac(0, imageid); 
     
    //make new image 
    document.getElementById(imageid).src = imageNewSrc; 

    //fade in image 
    for(i = 0; i <= 100; i++) { 
     	setTimeout("changeOpac(" + i + ",'" + imageid + "')",(timer * speed));
    	document.getElementById(imageid).src = imageNewSrc; 
        timer++; 
    } 
    changeOpac(0,imageid);
}