How to find the center co-ordinates of different regions

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Hi there,
Can anyone assist me how to find the center co-ordinates automatically and save the co-ordinate (x and y position) values in an array automatically? The shapes are different for the regions but each region has same pixel value.
Please have a look at my image and guide me how to find the center co-ordinates of each region and save them in an array automatically without using manual operation.
Any help will be highly appreciated.

Accepted Answer

Image Analyst
Image Analyst on 11 May 2015
Edited: Image Analyst on 11 May 2015
I thought you'd seen it before, but I guess not. See my image segmentation tutorial in my File Exchange http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862
Basically it's something like
grayImage = rgb2gray(rgbImage);
[labeledImage, numberOfBlobs] = bwlabel(grayImage ~= 0);
measurements = regionprops(labeledImage, 'Centroid');
allCentroids = [measurements.Centroid];
xCentroids = allCentroids(1:2:end);
yCentroids = allCentroids(2:2:end);
  7 Comments
Image Analyst
Image Analyst on 11 May 2015
If you want to treat the black background as its own object, then you'll have to do that separately (well, that's the simplest and most straightforward way).
grayImage = rgb2gray(rgbImage);
[labeledImage, numberOfBlobs] = bwlabel(grayImage == 0);
measurements = regionprops(labeledImage, 'Centroid');
allCentroids = [measurements.Centroid];
xCentroids = allCentroids(1:2:end);
yCentroids = allCentroids(2:2:end);
Note the == 0 instead of ~= 0 so that we pick up only pure black pixels.
Tania
Tania on 11 May 2015
Thank you very much. That solved my problem.
Great help

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