function getRandomNum(lbound, ubound) {
	return (Math.floor(Math.random() * (ubound - lbound)) + lbound);
}
var newnr=getRandomNum(1,5);
var oldnr=newnr;
var first=4;
function randomon() {
	if (first>0) document.images['homepic'+first].src='img/homepic'+first+'_off.jpg';
	pics=4;
	if (newnr<=pics) {
		document.images['homepic'+oldnr].src='img/homepic'+oldnr+'_off.jpg';
		document.images['homepic'+newnr].src='img/homepic'+newnr+'_on.jpg';
		oldnr=newnr;
		newnr=getRandomNum(1,5);
	}else {
		newnr=1;
	}
	first=0;
}
var interval='';
window.clearInterval(interval);
interval = window.setInterval("randomon()", 1000);

function flip(nr,onoff) {
	document.images['homepic'+nr].src='img/homepic'+nr+'_'+onoff+'.jpg';
}