var pic = "";

rollpic = function (img_name, img_src) {
document[img_name].src=img_src;
}

foto = function(pic){
rollpic('image', 'foto/gallery/' + pic + '.jpg');
}

function pup(pageURL, title) {
var w = 800;
var h = 600;
var left = (screen.width/2)-(w/2);
var top = (screen.height/2)-(h/2);
var targetWin = window.open (pageURL, title, 'toolbar=no, location=no, directories=no, status=no, menubar=no, scrollbars=no, resizable=yes, copyhistory=no, width='+w+', height='+h+', top='+top+', left='+left);
}