Importing pixel array in Excel and creating an image

Hello everyone,

A MATLAB beginner here. I would like to ask a quick question. I believe this is simple for a lot of you folks. I have an image in the form of pixel array in Excel sheet. I wish to create an image from this and also be able to set a certain threshold so that the numerical values of any pixels that do not meet the threshold become zero.

I really really appreciate everyone's help in advance!

[Caglar]

can you post your excel file?

[Johoon Kim]

Sorry for the lack of detail in my original question. Please see attached. It is a 128 x 100 matrix.

Answer 1

[Image Analyst]

Try this:

data = importdata('AuL_1.csv', ',', 5);
grayImage = data.data;
subplot(2, 2, 1);
imshow(imadjust(grayImage), []);
subplot(2, 2, 2);
histogram(grayImage);
grid on;
threshold = 4;
mask = grayImage < threshold;
% Erase mask pixels.
grayImage(mask) = 0;
subplot(2, 2, 3);
imshow(imadjust(grayImage), []);

[Johoon Kim]

This is exactly what I needed! Thank you!

[Johoon Kim]

Actually one more thing... Is it possible to assign a color of different shades to the white pixels depending on its intensity value? e.g. brighter yellow to pixels that originally had value of 4, a darker shade to 5, an even darker shade to 6, and so on.

Thank you so much in advance!

[Image Analyst]

Yes, just use ind2rgb() to create an RGB image. Or you can keep it grayscale and just use colormap() to change the way it's displayed.

[Johoon Kim]

Got it. Thank you again!