一組方向性次頻分解的濾波器及其紋理影像辨認上的應用

Abstract

這篇論文討論一種二維的方向性濾波器組.這種濾波器組是將頻譜作方向 性的切割,因此其輸出可提供方向性的訊息. 這種濾波器組可用最少的取 樣而不會遺失任何訊息. 換句話說,這些濾波器的輸出可以完全的回復原 來的訊號.除了這種濾波器的設計外,我們也考慮在實際完成時其遞迴或非 遞迴的架構所衍生的問題. 最後,我們將這種方向性濾波器組應用在紋理 影像的辨認. This thesis investigate a directionally oriented 2-D filter bank with the property that the individual channels may be critically sampled without loss of information. The passband regions of the component filters are wedge shaped and thus provide directional information. It is shown that these filter bank outputs may be maximally decimated to achieve a minimum sample representation in a way that permits the original signal to be exactly reconstructed. In addition, implementation issues are also addressed where realization based on both recursive and nonrecursive filters are considered. Finally, the directional filter banks are applied to the problem of texture recognition.