Accurate extraction of the image feature directions is essential to image smoothing and other image processing tasks. We show that the gradient-based feature direction extraction method can be very erroneous. The gradient is too local, and it cannot detect oscillations. We have developed two new methods: the Hessian method, an approach using higher order differentiations, and the Gabor method, an approach using space-frequency analysis.
All Science Journal Classification (ASJC) codes
- Computer Graphics and Computer-Aided Design
- Adaptive smoothing
- Anisotropic diffusion