how to mask an image?

 I = imread('E:\M.E 3rd semester\project\coding\flower.jpg');
 I = rgb2gray(I);
 J=ones(3,3)/9;
 K = conv2(I,J,'same');

Warning: CONV2 on values of class UINT8 is obsolete. Use CONV2(DOUBLE(A),DOUBLE(B)) or CONV2(SINGLE(A),SINGLE(B)) instead.

Can anyone help to correct the error?

[Image Analyst]

That's not masking an image - that's blurring it with a box (or sliding mean) filter. But like the others said, you need to case to double before convolving. Masking would be like setting inside or outside a region to some value or creating an ROI. For example you could mask your image so that the blurring just occurred inside a big circle in the middle of your image. Let me know if you want a masking demo.

[sheno39]

Thanks for your explanation. As am new to image processing in matlab it would be more helpful to me.

Answer 1

[Anand]

I = im2double(imread('..'));
I = rgb2gray(I);
J = ones(3)/9;
K = conv2(I,J,'same');

[sheno39]

thank you..

Answer 2

[Image Analyst]

Regarding your comment asking for a masking demo, one of mine is attached. Click on it below to see it.

Answer 3

[Matt J]

I = double(rgb2gray(I));

[sheno39]

I = double(rgb2gray(I));

Error using rgb2gray>parse_inputs (line 81) MAP must be a m x 3 array.

Error in rgb2gray (line 35) X = parse_inputs(varargin{:});

[Matt J]

 I = imread('E:\M.E 3rd semester\project\coding\flower.jpg');
 I = double(rgb2gray(I));

[sheno39]

thank you..