function change_media(obj, info) {
	$('.visible_info').addClass('invisible_info');
	$('.visible_info').removeClass('visible_info');
	$('.visible').removeClass('visible');
	$(obj).addClass("visible");
	$(document.getElementById(info)).removeClass('invisible_info');
	$(document.getElementById(info)).addClass('visible_info');
	document.getElementById('mediaInfoHeader').innerHTML=obj.innerHTML;
}