MATLAB: Multiplicative noise generate using randn

Question

I add additive '0' mean Gaussian noise to original image using

n=0+(sd)*randn(size(original image)) and i apply noise estimation algorithm to noisy image and i found additive noise.

If i needs to simulate noise estimation algorithm using multiplicative noise,how i generate noisy image with multiplicative noise? (only using 'randn' function, not using imnoise)

Answer 1

noiseOnlyImage = sd * randn(size(noiseFreeImage));
noisyImage = noiseFreeImage .* noiseOnlyImage;
% Cast to uint8 if you want.
imshow(noisyImage, []);  % Use [] if it's a double image.