EE $431$ Final Part $2(25$ pts$)$ Time allowed: $25$ minutes. Upload should be strictly finished by $14$:$30.$ Late submission is not allowed. Submit a single file named $($using your own name$)$ fin$2$name$\_$lastname.jpg $($or pdf$,$ etc.$)$

This is an open book, open notes, open research exam. But any kind of teamwork is strictly forbidden. By answering the following question you will be accepting the following statement: I pledge my honor, I have not given, received, or used any unauthorized assistance.

The first step in image restoration is finding an appropriate image degradation model. The most common choice is: $g(x,y)=f(x,y)**h(x,y)+n(x,y).$

a$)$ What do $g(x,y),f(x,y),h(x,y)$ and $n(x,y)$ stand for in the above equation? Which are known prior to image restoration and which are unknown?

b$)$ Describe how inverse filtering is typically implemented in the frequency domain. How are $g(x,y),f(x,y),h(x,y)$ and $n(x,y)$ used in this process?

c$)$ How would you model the image degradation situation where a photographer accidently moves a camera downward as they click on the shutter button?

d$)$ How would you use this information to restore the image?

e$)$ Why is inverse filtering approach practically useless? How can we modify it to make it useful?