bwarea & area, white/black ratio
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Hi,
Can someone please explain me what is the difference of bwarea & area.
I have an image which is black and white (after segmentation and fill) & I wish to calculate the area of an object (as I understand done by bwarea) relative to the image area (imageArea = regionprops(image_name, 'Area')), more or less calculating the white/black ratio.
Any other ideas is welcome.
Thanks.
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Accepted Answer
Image Analyst
on 3 Oct 2012
Edited: Image Analyst
on 3 Oct 2012
They use different algorithms. regionprops gives the number of pixels while bwarea gives some kind of weighted area that depends on the shape of the boundary. This is described in the documentation for bwarea
The white to black ratio is
totalPixels = numel(binaryImages);
numWhitePixels = sum(binaryImage(:));
numBlackPixels = totalPixels - numWhitePixels;
ratio = numWhitePixels / numBlackPixels;
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More Answers (1)
dan kin
on 3 Oct 2012
3 Comments
shivam sahil
on 21 Dec 2017
Hey! I want to implement the same code for RGB to get pixel count of particular rgb index, please guide me with the code for the same.
Image Analyst
on 22 Dec 2017
See attached demo. Also see the function colorcloud().
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