# count rectangular and circles

13 views (last 30 days)
Tu Nguyen on 14 Apr 2022
Commented: DGM on 15 Apr 2022
Hi all,
I want to count how many rectangular and circles in the image? what is the difference between rectagular and circle in matlab regionprops?
Also, I want to count how many rectangular and circles, both with holes in the image?
Finally, I want to export a figure just square and rectangular only.
clc;
close all;
clear;
A = imbinarize(A);
[label counts]= bwlabel(A);
imshow(A);
stats = regionprops(A,'Circularity','Centroid','Area','Perimeter','Solidity','FilledArea');
filledImage = imfill(A,'holes');
boundaries = bwboundaries(filledImage);
circularity = [stats.Circularity];
perimeters = [stats.Perimeter];
area = [stats.Area];
filledarea = [stats.FilledArea];
solidities = [stats.Solidity];
Centroid = [stats.Centroid];
circularities = perimeters.^2./(4*pi*filledarea);
hold on;
for blobNumber = 1 : counts
if circularities(blobNumber) < 1.19
theLabel = 'Circle';
elseif circularities(blobNumber) < 1.53
theLabel = 'Rectangle';
else
theLabel = 'Triangle';
end
text(stats(blobNumber).Centroid(1), stats(blobNumber).Centroid(2),...
theLabel, 'Color', 'r');
end
##### 3 CommentsShow 1 older commentHide 1 older comment
Tu Nguyen on 14 Apr 2022
I read the answer, however, they use a function minboundrect that is the built-in function. Do you have any method that classify rectangular and circles ny metric value?
DGM on 15 Apr 2022

yanqi liu on 15 Apr 2022
yes，sir，use regionpropers to find difference between rectagular and circle, may be use：
Circularity、BoundingBox
such as
bwi = imcrop(bw, round(stats(i).BoundingBox));
rate = nueml(find(bwi(:)))/numel(bwi);
now we can find rectagular get more rate than circle, may be try it.

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