function next_image(){
	n=parseInt(document.hform1.glr_cindex.value);
	n++;
	imglist=document.getElementsByName("glr_imglist");
	if (n>imglist.length) return;
	document.obrazok.src=imglist[n].value;
	document.hform1.glr_cindex.value=n.toString();
	document.cntform.counter.value=(n+1).toString() + " z " + imglist.length;
}

function prev_image(){
	n=parseInt(document.hform1.glr_cindex.value);
	n--;
	imglist=document.getElementsByName("glr_imglist");
	if (n<0) return;
	document.obrazok.src=imglist[n].value;
	document.hform1.glr_cindex.value=n.toString();
	document.cntform.counter.value=(n+1).toString() + " z " + imglist.length;
}