MATLAB: How to calculate Area ?

image processingImage Processing Toolbox

Hey every body….

I am asking "how can i compute area of the bounding box and convex hull where i had already get it's parameters?"

Thank you

Best Answer

If you have the vertices of the convex hull, use the polyarea() command.

Related Solutions

MATLAB: Drawing bounding box for the skew text regions

Use bwconvhull() and regionprops()

binaryImage = grayImage < 128; % Threshold.
joinedBlobs = bwconvhull(binaryImage, 'union'); % Get convex hull of all blobs.
props = regionprops(joinedBlobs, 'BoundingBox'); % Find bounding box.
boundingBox = props.BoundingBox; % Pull from field of structure into 1x4 vector.

You'll have to get rid of that outer black box first though so that you have ONLY the letters and not some frame or boundary.

To determine angle of skew, you might look at the radon transform. Demo attached.

MATLAB: How to find the area of each bounding box of an image

BB = vertcat(compBinaryFeat.BoundingBox);
BBarea = BB(:,3).*BB(:,4);

Caution: the bounding box of the center object includes the bounding boxes of two smaller objects. You should think about whether you really want the area of the bounding boxes, or if instead you want the areas of the objects -- which you can get by requesting the Area property.

Also I suggest you look at bwareafilt() unless you are using an older MATLAB.

Best Answer

Related Solutions

MATLAB: Drawing bounding box for the skew text regions

MATLAB: How to find the area of each bounding box of an image

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