How to detected isolated/closed contours?

Hello. I'd like to know if there are any functions that I can use to detect detached and isolated closed contour lines. I've obtained the contour lines by using:

[C,h] = contourf(...)

But C gives location of points in contours of the same value, and I find it hard to sort out those which forms a close loop and those spread over the space domain. I wonder if there're any algorithms to detect closed contour / detached filament like those in the following image? (I use arrows to indicate some filaments of interest)

Thanks for any kind help.

Answer 1

[Image Analyst]

I think you should be able to use imregionalmax and imregionalmin in the Image Processing Toolbox.

Or, maybe try this: http://www.mathworks.com/matlabcentral/fileexchange/35452-finddepressions