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From: alonso hauer on 8 Dec 2009 01:50
Hi there,
thanks for reading. I was given a 2-D video with about 1000 frames with the light intensity of a chemical wave that has a closed-shape form and propagates. I did obtain a decent contour of the wave by doing a threshold and a gaussian filter. This resulted on having the coordinates of the wave edge (Xe,Ye). Now, I need to calculate points of maximum 2-D curvature. I have read things about fitting a polynomial to the edge using polyfit. In my case, I guess that won't work since my function Ye(Xe) is multivalued and has turning points (it is a closed-shape form). I have heard that once you have that polynomial fit you could fit a circle to points along the edge and obtain the radius of curvature (curvature^-1) at each point. My questions

1) I could fit the circle to those points, but I don't think that will work since I can't fit the edge to an analytic function for the reasons above, can I?.

2) You guys know of any matlab routine that does this automatically (i.e., one with input {Xe, Ye(Xe)} and output Curvature(Xe,Ye(Xe))?.

Thanks!
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