function change_galpic(num, total) {
	for(n=0;n<total;n++){
		if(document.getElementById("galpic_id_"+(n+1)).style.visibility == "visible"){
			document.getElementById("galpic_id_"+(n+1)).style.visibility = "hidden";
		}
	}
	document.getElementById("galpic_id_"+num).style.visibility = "visible";
}