Question

Type in MATLAB code

1 Download from the class web page the image Fig5.07(b)jpg (X-Ray image corrupted by Gaussian noise) (a) Write a computer program to implement the arithmetic mean filter of size 3x3. Apply the program to the image Fig5.07(b).jpg (b) Write a computer program to implement the geometric mean filter of size 3x3. Apply the program to the image Fig5.07(b).jpg

Figure5.07(a)

Figure5.07(b)

Answer 1

CODE:

K = imread('C:\lena.bmp');

subplot(2,5,1),imshow(K),title('original image');

I=imnoise(K,'gaussian');

subplot(2,5,6),imshow(I),title('Image with gaussian noise');

%contrahormonic filter

data=im2double(I);

Q=-2;

sumn=[];

sumd=[];

pixln=0;

pixld=0;

ro=512;

col=512;

for i=1:ro;

for j=1:col;

for m=-1:1;

for n=-1:1;

if (i+m>0 && i+m<ro && j+n>0 && j+n<col && ... % To keep indices in limit

1+m>0 && 1+m<ro && ...

1+n>0 && 1+n<col)

pixl1=(data(i+m,j+n)).^(Q+1);

% Application of Formula

pixl2= (data(i+m,j+n)).^Q;

pixln=pixln+pixl1; % Application of Summation

pixld=pixld+pixl2;

end

end

end

reformedimage(i,j)=(pixln/pixld);

pixln=0;

pixld=0;

end

end

subplot(3,5,5),imshow(reformedimage),title('contra-harmonic mean (Q=-ve)');

data=im2double(I);

Q=2;

sumn=[];

sumd=[];

pixln=0;

pixld=0;

ro=512;

col=512;

for i=1:ro;

for j=1:col;

for m=-1:1;

for n=-1:1;

if (i+m>0 && i+m<ro && j+n>0 && j+n<col && ... % To keep indices in limit

1+m>0 && 1+m<ro && ...

1+n>0 && 1+n<col)

pixl1=(data(i+m,j+n)).^(Q+1); % Application of Formula

pixl2= (data(i+m,j+n)).^Q;

pixln=pixln+pixl1; % Application of Summation

pixld=pixld+pixl2;

end

end

end

reformedimage(i,j)=(pixln/pixld);

pixln=0;

pixld=0;

end

end

subplot(3,5,7),imshow(reformedimage),title('contra-harmonic mean (Q=+ve)');