var ctnrHeight;
var r = 0;
var frameHeight = 274;
var originalTop = 206;
var ctnrTop = 0;

function ThumbInitial(ctnrImgCount) {
	ctnrHeight = (ctnrImgCount * 91) + 1;
	r = (ctnrHeight - 60) / (frameHeight - 60);
}

function ThumbOnMouseClick(f) {
	var img = document.getElementById('imgDisplay');
	img.src = 'Images/' + f + '.jpg';
	
}

function ThumbOnMouseOver(i) {
	i.className = 'Hover';
}

function ThumbOnMouseOut(i) {
	i.className = '';
}

function ThumbOnMouseMove(evt) {
	
	if (r!=0) {
		var x, y;
		if (document.all) {
			y = event.y + ctnrTop;
		} else {
			y = evt.pageY - originalTop;
		}
	
		ctnrTop = (y - 30) * (1 - r);
		if (ctnrTop > 0) {
			ctnrTop = 0
		} else if (ctnrTop + ctnrHeight < frameHeight) {
			ctnrTop = frameHeight - ctnrHeight;
		}
	
		document.getElementById('divThumbCtnr').style.top = ctnrTop + 'px';
	}
}