Recursive Implementation of LoG Filtering

✍ Scribed by Jesse S. Jin; Yan Gao

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 370 KB
• Volume: 3
• Category: Article
• ISSN: 1077-2014
• DOI: 10.1006/rtim.1996.0045

✦ Synopsis

Recursive Implementation of LoG Filtering

oG filters have been widely used as a second derivative filtering function. One problem with LoG filtering is that it is very time consuming, especially with a large size filter. We use an Lanal ytical method to obtain the z-transform of LoG function in a rational function form and develop a recursive implementation. The structure of the recursive filters is defined by the order of rational functions. The algorithm gives a constant computation complexity per pixel. The computational complexity of recursive filtering depends on the number of poles and zeros of the transfer function, i.e., on the structure of the recursive filter. It is independent of the size of the filter, and thus has a substantial saving in computation. A general method of designing high order recursive filters is also given. Recursive functions can be implemented in a number of shifting registers in hardware. The methodology will contribute to real-time image processing and robot vision.