noise is added to the central region of each image

noise is added to the central region of each image ???

Answer 1

[KALYAN ACHARJYA]

Considering im is a gray level image, and the central part of the image considered as mid section of the image as per its rows and clumns number or you may change the segment as per your requiremnt.

original_im=im;
[r,c]=size(im);
cent_part=im(round(r/4):round(3*r/4),round(c/4):round(3*r/4));
im(round(r/4):round(3*r/4),round(c/4):round(3*r/4))=cent_part+imnoise(cent_part,'gaussian');
% You can add any other types of noises here,'gaussian' just for example 
imshow([original_im,im]);
title('Priginal Image     Noise Added Image');

[arwa allubani]

thank you KALYAN ACHARJYA