Can a skeleton be defined on a neighbourhood of 8 pixels ?

[Jean-Patrick Pommier]

Hi,
Is it possible to skeletonize a binary 2D shape such that  its skeleton is 
defined on a neighbourhood of 8 pixels?

When skeletonizing with  : *morphology.medial_axis()* , I tried two 
structuring elements (se8 or se4) as mask :

se8 = np.array([[True,True,True],[True,True,True],[True,True,True]])
se4 = 
np.array([[False,True,False],[True,True,True],[False,True,False]])                       

imK = makeLetterImage('K', 70)
skel = *morphology.medial_axis*(imK,mask=se8) 
Ep_Bp, Bp_Bp, Bp, Ep = SkeletonDecomposition(skel)

The skeletons returned using se8 or se4 are very similar and look defined 
on a neighbourhood of 4 pixels (left). To me, this is a problem when trying 
to label the skeleton edges (right).

<https://lh4.googleusercontent.com/-curcY_g5N9A/U5BfJdpe6yI/AAAAAAAAB0w/1PbxFHLHJ6s/s1600/labeling+edges.png>

Jean-Patrick
<https://lh4.googleusercontent.com/-curcY_g5N9A/U5BfJdpe6yI/AAAAAAAAB0w/1PbxFHLHJ6s/s1600/labeling+edges.png>
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