find homogeneities of each block of quadtree decomposed image

Hello,

The above image is the light house image and its quadtree decomposed image using Matlab.

What I'd like to do is to find the homogeneity of each block from the quadtree decomposed image.

I think I need to get the exact position of black region of each block and then find the homogeneity from RGB (or gray) image with these position of black region.

Any advice is warmly welcome. Thank you.

Answer 1

[Image Analyst]

Try this:

grayImage = imread('liftingbody.png');
S = qtdecomp(grayImage,.27);
blocks = repmat(uint8(0),size(S));
[rows, columns] = size(S)
for row = 1 : rows
    for col = 1 : columns
        if S(row, col) ~=0
            upperLeftRow = row;
            upperLeftCol = col;
            width = S(row, col);
            height = S(row, col);
            hold on;
            boundingBox = [upperLeftCol, upperLeftRow, width, height];
            rectangle('position', boundingBox, 'EdgeColor','r', 'LineWidth',2)
            % Extract the subimage
            thisBlock = imcrop(grayImage, boundingBox);
            % Compute mean
            thisMean = mean2(thisBlock);
            stdDev = std2(thisBlock);
        end
    end
end