Q$3.$

$(8)$

Median filters are used to remove noise from

$\backslash$table$[[0,0,1,0,0,0],[1,0,0,1,0,1],[0,1,1,0,1,0],[1,0,0,1,0,1],[1,0,1,0,0,0]]$

image especially salt and pepper noise. However, user has to define the window size before applying filter. On the other hand, adaptive median filter changes size of Sxy $($the size of the neighborhood$)$ during operation. The algorithm for adaptive median filter is given below.

Notation

Zmin $=$ minimum gray level value $inSxy$

$Z$ max $=$ maximum gray level value $inSxy$

$Z$ med $=$ median $of$ gray levels $inSxy$

$Zxy=$ gray level $at$ coordinates $(x,y)$

Smax $=$ maximum allowed size $ofSxy$

Algorithm

Level A: A$1=$ Zmed $-$ Zmin

A$2=$ Zmed $-$ Zmax

if $A1>0$ AND go to level $B$

else increase the window size

if window size $$ Smax, repeat level $A$

else output $Zxy$

Level B: B$1=$ Zxy $-$ Zmin

B$2=$ Zxy $-$ Zmax

if B$1>0$ AND B output Zxy

else output Zmed

An $88$ image is given in figure below. Apply this algorithm on pixel $(5,5)$ only with original value $=112$ image. Give final value for this pixel after applying adaptive median filtering.

$\backslash$table$[[10,143,210,0,0,10,110,170]]$

$\frac{14}{2}|P|$ a g e

$\backslash$table$[[110,54,60,0,111,211,139,102],[60,63,111,71,161,105,10,70],[10,11,255,0,0,15,255,70],[0,50,190,0,112,0,6,200],[0,130,10,0,115,175,75,200],[60,0,150,10,200,61,255,50],[255,105,111,41,211,113,201,106]]$