Gradient Vector Flow Snake

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Gradient Vector Flow Snake

• C. Xu and J. L. Prince
• Project by Charlie Neo

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Problem Description

• Finding Object Boundaries
• Snake (Active Contour)
• Initialization problem
• Poor convergence to boundaries concavities
• C. Xu and J. L. Prince, Snakes, Shapes, and
  Gradient Vector Flow,'' IEEE Transactions on
  Image Processing, 7(3), pp. 359-369, March 1998.

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Algorithm (GVF)

• Edge map f (x,y) from Image
• Gradient vector flow field
• That minimizes energy function
• GVF can be found by solving Euler equation as a
  function of time

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Implementation

• Setup the iterative solution

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Implementation cont.

• Force balance equation.
• Using GVF field as the internal force.

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Testing
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Testing
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Testing
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Testing
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Testing
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Testing
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Future Work

• Better initialization method.
• Optimization.