How to Make a square image of size= 256 * 256 and fill it diagonally with 11 black pixels and 20white pixels ?

clear all close all

for row=1:256 for col=1:256 a(row,col)=1

       end

    end
end
figure,imshow(a)

[Wayne King]

There will be 256 elements on the main diagonal, so how exactly do you want these 11 and 20 to be chosen?

Answer 1

[Image Analyst]

Try this:

width = 256;
% Create some initial sample data (all 99's).
myArray = 99 * ones(width, width, 'uint8');
% Make 11 black pixels.
for k = 1 : 11
  myArray(k,k) = 0;
end
% Make 20 white pixels.
for k = 12 : 31
  myArray(k,k) = 255;
end

and read this: http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer