var minAncho = 478;
var minAlto = 338;

var winName = "titulo";
var win = null;

function AbreVentana( theURL, ancho, alto, nomVentana, mosBarra )
{
    var h = (screen.width-ancho)/2;
    var v = (screen.height-alto)/2;
    
    if (mosBarra != 1)
        mosBarra = 0;
    
    var windowprops = "top=0,left=0,toolbar=no,location=no,status=no,menubar=no,scrollbars="+mosBarra+", resizable=no,width="+ancho+",height="+alto+",left="+h+", top="+v;
    
    if (win)
    {
        win.close();
    }
    
    win = window.open(theURL, nomVentana, windowprops);
}

function CambiaImg( idElemento, imagen )
{
    document.getElementById( idElemento ).src = imagen;
}