var fDesc=new Array();
fDesc[0] = "The Fourier Transform is a powerful tool allowing us to move back and forth between the spatial and frequency domains. This applet helps students feel comfortable, helping to build a strong intuitive grasp of how signals in one domain correspond to signals in the other.<br /> <br /> Students can load scanlines from common image patterns and see that scanline&#039;s Fourier Transform in real-time. For example, they can load the scanline of a standard test image to note how most of the energy is concentrated at low frequencies -- a key to why low-pass filtering doesn&#039;t render an image unintelligible.";

function tShowHide(id, show)
{
	var s = document.getElementById("desc");

	if ((s.innerHTML.length<=212 || show==1) && show!=2)
	{
		s.innerHTML = fDesc[id];
		if (document.getElementById('m1'))
			document.getElementById('m1').style.display='none';
		if (document.getElementById('m2'))
			document.getElementById('m2').style.display='none';
		if (document.getElementById('more_txt'))
			document.getElementById('more_txt').style.display='inline';
	}
	else
	{
		s.innerHTML = '';
	}
}