How can I sum the centroids of blobs and display in the same image?

I have an image with a number of objects. I've labelled the objects and need to isolate the blobs with a certain feature. I've used a "for" loop to run through the objects and within the "for" loop I have used an "if" loop to find the blobs with the feature. How can I get the centroids of the blobs that result from the "if" loop and overlay their centroids togehter on the original image using markers?

Answer 1

[Image Analyst]

This is completely explained in my Image Segmentation Tutorial: http://www.mathworks.com/matlabcentral/fileexchange/25157-image-segmentation-tutorial