MATLAB: Obtaining Histogram of Image Stored in Cell Array

Question

Hello,

I have a cell array called output. Output contains matrices of size 1024 x 1024, type = double, grayscale. I would like to plot each matrix and its corresponding histogram on a single plot. Here is what I have so far:

for i = 1:size(output,2)
    figure 
    subplot(2,1,1)
    imagesc(output{1,i});
    colormap('gray')
    colorbar;
    title(num2str(dinfo(i).name))
    subplot(2,1,2)
    [pixelCount, grayLevels] = imhist(output{1,i});
    bar(pixelCount);
    title('Histogram of original image');
    xlim([0 grayLevels(end)]); % Scale x axis manually.
    grid on;
end

The plot I get, however, seems to be faulty… I was expecting a distribution of bars.

I am somewhat lost at how to proceed, any help or suggestions would be appreciated!

Thanks 🙂

Answer 1

Instead of this

[pixelCount, grayLevels] = imhist(output{1,i});
bar(pixelCount);

try this:

histogram(output{1,i}, 256);
grid on;