Functions > Image Processing > Image Manipulation > Addition and Noise Measurement
  
Addition and Noise Measurement
addnoise(M, p, n)—Returns matrix M with added noise, with probability p/2 to add or subtract n to or from the pixel intensity.
The addnoise function clips the resulting pixel values to the range 0 to 255.
Arguments
M is an image matrix.
p is a real number between 0 and 1, inclusive.
n is a real number with absolute value between 0 and 255, inclusive.