How to draw bounding box around white area in binary image

this test image Promblem I want draw bounding box and know angle of image 4 angle

Answer 1

[Image Analyst]

Use regionprops() to get the bounding box.

I don't know what "angle of image 4 angle" is.

[Adisorn Phanukthong]

Angle of image top left measured from the center

please write code use boundingbox

[Walter Roberson]

Angle? As in the arctan of the ratio between the height and width?

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/87597-rectangle-around-the-object-bounding-box

[Image Analyst]

Try this:

[labeledImage, numRegions] = bwlabel(mask);
props = regionprops(labeledImage, 'BoundingBox');
hold on;
% Plot the bounding box around each region.
for k = 1 : numRegions
    thisBB = props(k).BoundingBox;
    rectangle('Position', thisBB, 'Color', 'r');
end

[Adisorn Phanukthong]

Thank you I start learn in matlab in 2 month

[Adisorn Phanukthong]

Yes Angle as between the height and width

[Walter Roberson]

angle = atan2(thisBB(4), thisBB(3))