Better Skeletonization

Provides an alternative to the image toolbox skeletonization implemented in bwmorph.

Description

The files in this package comprise the Matlab implementation of a method for skeletonizing binary images. These are my own implementation
of a skeletonization method communicated to me by Alex Telea
(http://www.win.tue.nl/~alext/). See his papers for more details.

Skeletonization is (roughly speaking) the "thinning" of a binary image or silhouette to a one-pixel width spine. The image processing toolbox provides support for skeletonization via the bwmorph function, but its results do not always conform with our intuition. I have found that the approach used herein usually generates a more pleasing result.

There is also a routine for locating endpoints and junctions in skeletonized images.

(Note: This code has not been optimized for speed.)

Bug fix 7/18/07: In rare instances, isolated points would incorrectly be assigned an infinite value for skg.

Acknowledgements

This file inspired Anaskel Written In Matlab, Tree Labelling, and Vessel Branch Segmentation.

• Required Products: Image Processing Toolbox
• MATLAB release: MATLAB 7.0.4 (R14SP2)

[Athanasios Balomenos]

Nice work, but can I ask you something. How we may compute the threshold (you demostrate in demo file) automatically according to the given object nowing only its shape apriori? Can you give the exact reference of the algorithm?

[Paul]

Good

[donny jason]

i got it already. It works. Thank you

[donny jason]

I have try other compiler.I'm using mic studio professional 2008. It seems it is still the same..
how to solve it?

[Christopher MacMinn]

With regard to my question above (15 Sep 2009), I think I've figured it out -- it looks like the local radius output of the function skeleton() is actually the radius SQUARED. Take the sqrt to get the radius in pixels.

[Christopher MacMinn]

This package is very useful.

A question: does anyone know what the local radius values correspond to, or what units they are measured in? They are not in pixels.

[Matt Fetterman]

It is very good. I have suggestions for additional features if you are interested in collaboration.

[Casey Ta]

For those having trouble compiling skeleton.m and anaskel.m, I had the same issue at first. The Lcc-win32 C 2.4.1 compiler that comes with MATLAB wouldn't compile these files. You'll have to try a different compiler. These files compiled just fine for me after I chose Microsoft Visual Studio 2008 in mex -setup.

[Sravanti]

I am a Matlab novice, having said that, this code also doesn't work for me, i ran the mex setup, chose a compiler, changed the file path names in skeleton.m and anaskel.m to the correct ones for the cpp files (from the download) - do I need to make any modifications in the C-code? how does it read the image?
I get lots of errors from the .cpp files

[elden fisher]

it works. you have to modify and run first skeleton.m and anaskel.m as they contain absolute path to the two cpp files for compilation.

[Fadi Bazzi]

This thing do not work right. Can someone help me? I am getting those errors:

??? Attempt to execute SCRIPT skeleton as a function:
C:\Users\Fkb\Documents\MATLAB\test\skeleton.m

Error in ==> demo at 9
imshow(bwmorph(skeleton(img)>35,'skel',Inf));

[Luis Felipe]

Very good.

[Jinghong Low]

Thanks for your contribution

[Scooter NGC]

 

[Vincent Pelletier]

Nice. For me it turns out that anaskel is the useful routine after all. I'm glad I tried it!

[Arvin Fan]

It works.