Problem with cell array and mat2gray

Hi everyone i have written the next code that reads multiple images whose names start with specific numbers and then does some changes to those images

clc; clear; 

outLoopValues = number; 
for k = 1 : numel(outLoopValues)
	index = outLoopValues(k);
    
        outLoopValues2 = size; 
        for r = 1 : numel(outLoopValues2)
	    index2 = outLoopValues2(r);
     
		thisBaseFileName = sprintf('%d.%d0.png', index2, index);
		thisFileName = fullfile(folder, thisBaseFileName);
		    
            images{index2, index} = imread(sprintf('%d.%d0.png', index2, index));
            I1{index2, index} = images{index2, index}(:,:,1);
            Icrop{index2, index} = imcrop(I1{index2, index},[1 1 100 100]);
            Inew = Icrop(~cellfun('isempty', Icrop));
            inpsur1{index2, index}=double(Icrop{index2, index});
            Idetrended=mat2gray(inpsur1');
            I=uint8(255*Idetrended);
           I1=imadjust(I);
           I2 = medfilt2(I1,[3 3]);
           z=I1;
            
            
       
        end
end

but i get the next error:

Error using mat2gray
Expected input number 1, A, to be one of these types:

logical, uint8, uint16, uint32, int8, int16, int32, single, double

Instead its type was cell.

does anyone know how can i fix this?

Answer 1

[Walter Roberson]

Idetrended = cellfun(@mat2gray, inpsur1', 'UniformOutput', 0);
I = cellfun(@im2uint8, Idetrended, 'UniformOutput', 0);
I1 = cellfun(@imadjust, I, 'UniformOutput', 0);
I2 = cellfun(@(img) medfilt2(img, [3 3]), 'UniformOutput', 0);

Several of those steps can be combined if you do not have a use for the intermediate variables.

[lena kappa]

Thanks @Walter Roberson for your time but i get the following error:

Error using cellfun
Input #2 expected to be a cell array, was char instead.

Error in Untitled (line 29)
            I2 = cellfun(@(img) medfilt2(img, [3 3]), 'UniformOutput', 0);
 

also what do you mean they can be combined ? how?

[lena kappa]

I think that it should be

I2 = cellfun(@(img) medfilt2(img, [3 3]), I1, 'UniformOutput', 0);

[lena kappa]

but what do you mean by : Several of those steps can be combined if you do not have a use for the intermediate variables?

Thanks again @Walter Roberson have a nice day!

[Walter Roberson]

I2 = cellfun(@(img) medfilt2(img, [3 3]), I1, 'UniformOutput', 0);

[lena kappa]

wait isn't this the exact same thing i wrote in the comment above?

[Walter Roberson]

Yes, you posted while I was composing my reply.

[Walter Roberson]

%one combined step
I2 = cellfun(@(rgbimg) mefilt2(imadjust(im2uint8(mat2gray(rgbimg))), [3 3]), inpsur1.', 'uniform', 0)