how to create noise manually to a color image without imnoise function explain with example?

how to create noise manually to a color image without imnoise function explain with example?

[Image Analyst]

Duplicate of http://www.mathworks.com/matlabcentral/answers/72393-how-do-i-add-noise-to-a-color-image-without-using-imnoise-function

Answer 1

[Iman Ansari]

Hi. For gaussian noise with standard deviation of S:

clear
S = 20;
I = imread('peppers.png');
J = double(I) + S.*randn(size(I));
figure;
subplot(121)
imshow(I)
title('Original Image')
subplot(122)
imshow(J./255)
title('Additive Gaussian Noise')

Answer 2

[muhammad khatib]

clear

S = 20;

I = imread('peppers.png');

J = double(I) + S.*randn(size(I));

figure;

subplot(121)

imshow(I)

title('Original Image')

subplot(122)

imshow(J./255)

title('Additive Gaussian Noise')