erosion only pixels with value 50 and 51 in grayscale image

I have a grayscale image with pixels values 2, 3, 4, 50 and 51. I need to erode only a pixels with value 50 and 51(it represents the clouds). The result should be picture with pixels values 2,3 and 4. Can you please help me with this.

Answer 1

[Image Analyst]

Try this:

windowSize = 3; % Whatever you want
erodedImage = imerode(grayImage, true(windowSize));
% Get map of where the 50 and 51 are
mask = grayImage >= 50;
% Replace only those locations with the eroded pixels.
grayImage(mask) = erodedImage(mask);

Of course, you will still have 50 and 51 in the output image if those regions are larger than your mask regions.

[nm]

thank you from answer, but if i apply this the size of the matrix is 13112x1, it doesn´t work

[Image Analyst]

You did something wrong. I just tried it and it works. See my attached demo. Then attach your demo.

[nm]

Thank you very much, it was my fault, it really works :D