var interval = 5;		// delay between rotating images (in seconds)
var random_display = 1; // 0 = no, 1 = yes
var number_of_image = 22;
var base_url = 'images/banner/banner';
interval *= 1000;

function generate(x, y) {
	var range = y - x + 1;
	return Math.floor(Math.random() * range) + x;
}
function getNextImage() {
	var image_index = 0;
	if (random_display) {
		image_index = generate(0, number_of_image-1);
	}
	else {
		image_index = (image_index+1) % number_of_image;
	}
	return (base_url + image_index + '.jpg');
}
function rotateImage(place) {
	document[place].src = getNextImage();
	var recur_call = "rotateImage('"+place+"')";
	setTimeout(recur_call, interval);
}