After obtaining the pixel values of an image..how to store those pixel values in an array?

After obtaining the pixel values of an image..how to store those pixel values in an array?

[Walter Roberson]

how are you obtaining pixel values ?

[Kamali M]

clc;
close all;
my_image =imread('football.jpg');
figure,imshow(my_image);title('Orginal Image In Colour');


my_image=rgb2gray(my_image);
figure,imshow(my_image);title('Orginal Image In Gray scale');

% my_image = imresize(my_image,[512 512]); if you want to fix image size as constant

[rows,columns,depth]=size(my_image);  % Here row and columns of particular image are fetched 

for R=1:rows
    for C=1:columns
        pixel=my_image(R,C);
        disp (R)
      
    end
end

[Kamali M]

If this isnt correct please say that method also along with how to load them in an array?

thanks in advance.

[Guillaume]

Kamali, you have to explain better what it is you want to do. As commented you already have the pixels in an array. It's the my_image array

Answer 1

[madhan ravi]

pixel = cell(1,rows);
ctr = 1;
for R=1:rows
    for C=1:columns
        pixel{ctr}=my_image(R,C);
        disp (R)      
    end
    ctr = ctr+1;
end
celldisp(pixel)
[pixel{:}] % double array

[Walter Roberson]

pixel{ctr}( C) = ...

otherwise you overwrite .

[madhan ravi]

Thank you sir Walter.

[Guillaume]

The whole question is very puzzling and this answer is just as much puzzling. As per Walter's answer, the pixels are already stored in an array: my_image.

All the above code does is very inefficiently copy only the red channel of the image array into a cell array. The same could be achieved much faster in just one line with:

pixel = num2cell(my_image(:, :, 1));

which is a complete waste of time and just use more memory to store the same information.

[madhan ravi]

Thank you Guillaume , you are completely right , just noticed after answering the my_image was already stored.

[Kamali M]

ACTUALLY my input is a 256X320 but i get only a single row with 256 elements in it.

my_image =imread('football.jpg');
my_image=rgb2gray(my_image);
[rows,columns,depth]=size(my_image);
pixel = cell(1,rows);
ctr = 1;
for R=1:rows
    for C=1:columns
        pixel{ctr}=my_image(R,C);   
    end
    ctr = ctr+1;
end
celldisp(pixel)
disp ([pixel{:}]); % double array

what are the necessary changes in it?

thanks in advance.

[madhan ravi]

@kamali see sir Walter's answer this is not the correct approach as mentioned by the peers.

Answer 2

[Walter Roberson]

The pixel values are already stored in my_image and do not need to be stored again .

Answer 3

[Kamali M]

@madhan sir, please tell me what should i change i dont get it..

thank u sir.

[Walter Roberson]

What data type do you need as output? What array size do you need as output? What difference do you intend between "pixel values" that you want stored, compared to what is already in my_array ?

Answer 4

[Saipraveen]

For the information of other users, In this file exchange - https://www.mathworks.com/matlabcentral/fileexchange/72535-image-to-c-c-array-converter, I have written a script to generate an array from an image. I convert the input image to monochrome and store the pixel values in hex format in a different file. It could be modified to suit your needs.

Hope that helps.