SIGNAL AND IMAGE PROCESSING MIDTERM MAKEUP EXAMINATION

$08.12\mathrm{.}2023$

Duration : $90$ Minutes

Student ID:

Name Surname:

Signature:

$\backslash$table$[[$Q$1(25)($L$01,$ L$02),$Q$2(25)($LO$2),$Q$3(25)($LO$3),$Q$4(25)($L$\mathrm{.}02),$TOTAL$],[,,,,]]$

Q$1)(25$ pts$.)$ Consider the following gravsale $8-$bit digital image for the questions $1$ and $2.$

Pixel values

$\backslash$table$[[65,25,55,65,25],[10,55,55,25,25],[25,25,65,10,65],[25,25,10,10,25],[25,65,10,25,10]]$

a$)$ Draw the histogram.

b$)$ Derive the probabilities for each gray level value.

c$)$ Apply histogram equalization.

d$)$ Re$-$draw the histogram.

Q$2)(25$ pts$.)$ a$)$ Apply weighted average filter $(33)$ to pixel location $(4,4),$ write new pixel value.

b$)$ What kind of filter is weighted average? Smoothing or sharpening?

c$)$ Apply Laplacian filter $($any version$)(33)$ to pixel location $(2,3),$ write new pixel value.

d$)$ What kind of filter is Sobel filter? Smoothing or sharpening?

e$)$ Apply midpoint filter to pixel location $(2,2),$ write the new pixel value.

f$)$ What kind of filter is midpoint? Smoothing or sharpening?

g$)$ Apply median filter to pixel location $(3,3),$ write the new pixel value.

h$)$ What kind of filter is median? Smoothing or sharpening?

Note: take all filter sizes as $33.$