Find a pattern in a point cloud.

Hi there, I’m a beginner and I’m trying to find a pattern in a cloud point to create a line on the contour of the object that I get from a Kinect or I want to match a predefine line in the contour of the cloud, I’m trying to do this with an image of a shoe. Anyone have an idea to achieve this problem with grasshoper or you can give some tips where can I find examples that involve a similar problem.    Attach is the cloud of points that I get with the Kinect.  Sorry for my bad English.