hi.... first of all i would like to introduce myself... my name is johan...
right now i'm doing my S1 thesis in information technology.....
i take image restoration topic and.... i'm a newbie in this topic (so... i
need a lot of help to understand about the step)
and.... i use handbook : image processing theory, algorithms, &
architectures by Maher A. Sid-Ahmed
it is said that one of the procedure of image restoration was like this :
1.obtain the edge or i could say doing some edge detection
in this step it should have input an image n output an image too right ?
2.compute the extend of the blur in x n y 
using the formula σ_x=√(∑_x▒〖(x-μ_x )^2 F(x)〗)
but in this step i dun really understand what the input... i suppose it
should be the result image in the edge detection
and then....
3.compute frequency response of deblurring function from the derived OTF
in this step it is said to calculate using this formula
Ĥ(u,v)=  1.0/(2πσ_x σ_y e^(-(u^2 σ_x^2+v^2 σ_y^2)/2)+1.0)
is it true that i could get the value of frequency response from that
formula ?
and then...
4.design an iIR filter
i really dont know what will be the input n the output from this step... n
i dont know how to design the iir filter... could anyone explain to me ? or
any useful link that explain how to do this step ? please... and i
suppose..... i would use butterworth filter but i dont really know how to
design it.... even i had already look some mathlab code from this link
http://www.csse.uwa.edu.au/~pk/Research/MatlabFns/FrequencyFilt/lowpassfilter.m
i looked in my handbook that the formula is a bit different but... i think
its allright to use one of the formula i choose... but... could anyone
explain to me how to get some impulse response, cutoff frequency, n some
other variable that would be used in this step
and the last step is...
5.apply the filter
and... i hanvent reach this step ^^ i'm still confuse about the 3rd and
4th step T_T

need help for explaining some details pleaseeee T_T or... any other
solution that more easy for me to understand the step ?
i would very appreciate for any help even it just a small thing
thanks..... thanks a lottttt.........