var current;

function initTabs(id){
	var obj = document.getElementById(id);
	tabOn(obj);
	current = obj;
}

function tabOn(obj){
	obj.style.backgroundImage = 'url(images/knop_actief.png)';
}

function tabOff(obj){
	if (obj != current) {
		obj.style.backgroundImage = 'url(images/knop_inactief.png)';
	}
}

function transp(){

	//maak transparant
	all = document.getElementsByTagName('table');
	
	for (i = 0; i < all.length; i++) {
	
		all[i].style.backgroundColor = "transparent";
		
	}
	
}

function rescue(selfId, id){
	if (parent.frames.length > 0) {
	    parent.location.href = self.document.location;
	}
	
}

function checkButton(){
	if (parent.frames.length == 0) {
	    document.getElementById('stop').style.display = 'none';
	    document.getElementById('play').style.display = 'inline';
	}
}