I'm still pretty confused about the right side images. How do they relate to the current image frequencies?

@unreal, the right image is the frequency transform of the left hand side image. In order to filter in the frequency domain, you would first convert your image (e.g. the picture of Kayvon) to the frequency domain and then multiply the result by a mask (which frequencies are you cancelling out? A low pass filter will preserve low frequency data. This is a high pass filter (see the disk) so you exclude low frequency information.). Then you can inverse transform the image in the frequency domain back to the spatial domain and you'll get a filtered image like the result on the right. In this case, only high frequency info / edges are preserved which is why you get strongest edges. Hope that explanation helps some! Sorry it's a bit verbose