var currentId=1;

function changeImage() {
	if(currentId == 1) {
		document.getElementById("slide" + 16).style.display = "none";
	} else {
		document.getElementById("slide" + (currentId - 1)).style.display = "none";
	}
	document.getElementById("slide" + currentId).style.display = "inline";
	if(currentId == 16) {
		currentId = 1;
	} else {
		currentId++;
	}
	setTimeout("changeImage()", 1500);
}