Advanced techniques for digital image processing

A new algorithm for enhancing a degraded grey scale image is proposed here. The enhancement algorithm is a locally adaptive Fourier filter which locates and analyzes the Fourier spectral information and then enhances the identifying features. Thus, it can achieve a better enhancement result than conventional homomorphic FFT techniques. By using a short space basis implementation, a large amount of memory space can be saved, consequently the computation speed is greatly improved.

The primary objective of this algorithm is to extract linear features from a noisy image. However, the algorithm also can be modified in order to enhance other different kinds of features.

The main advantages of this algorithm are:

1. It requires a small amount of computer memory; this makes it easy to implement in small computers.
2. It has fast processing speed.
3. It is powerful in extracting local linear features.