1. Blobs as Interest Points

• Characteristic scale

  • 2nd derivative of Gaussian.

• Normalize LOG

  • Basic Laplacian detector = local maxima of characteristic scale.
  • LOG is good for finding scale.

• Use difference

2. Combine the Harris and Laplace

• Combine methods to enhance detection and reliability.

3. SIFT

• Scale-Invariant Feature Transform (SIFT).