Ideal Lowpass Filter

The Ideal Lowpass Filter (ILPF) blocks off the higher frequencies which are above the cutoff frequency Do, and only lets the
lower frequencies pass. Since the higher frequencies contain the detail information blocking them off causes a blurring
of the image. The decrease in the blurring when Do is increased can be seen below. Also these are analogous to the
smoothening filters in the spatial domain.


`The Original Image`	`Image after using the ILPF` `with Do = 10`	`Image after using the ILPF` `with Do = 30`	`Image after using the ILPF` `with Do = 60`

`Fourier Spectra of Original Image`	`Fourier Spectra after using the ILPF` `with Do = 10`	`Fourier Spectra after using the ILPF` `with Do = 30`	`Fourier Spectra after using the ILPF` `with Do = 60`

A 3D plot of the fourier spectra after applying the ILPF
(The X - Y ranges have been modified to get a better view of the plot)

Page last updated on 28 January, 2004.	`AT cse.iitd.ac.in`	© Parag Chaudhuri , 2009