This is an extremely simple m-file which implements the method described in :
J. Immerkær, “Fast Noise Variance Estimation”, Computer Vision and Image Understanding, Vol. 64, No. 2, pp. 300-302, Sep. 1996
The function inputs a grayscale image I and returns Sigma, the noise estimate. Here is a sample use:
I = rgb2gray(imread('sample.jpg'));
The advantage of this method is that it includes a Laplacian operation which is almost insensitive to image structure but only depends on the noise in the image.
In this source code, is M=[1 -2 1; -2 4 -2; 1 -2 1] correct ? I am asking this because the Laplacian kernel is M=[0 -1 0; -1 4 -1; 0 -1 0]. Please tell me which one is correct.
This might sound very lame but can you please tell guide me from point to point as to how to run this file? Its very urgent