非線上手寫中文字元筆劃抽取

Abstract

本論文的主要目的是利用一些中文筆劃的知識 (Knowledge)，來做手寫中 文字字元筆劃的抽取。對一個中文字影像，我們首先經過細字化( Thinning)､特徵點檢查 (Detection of feature points)､線段抽取 (Extraction of line segments)､線段型態判定 (Determination of line segment types)､去掉短線段(Deletion of short line segments) 等步驟的先前處理(Preprocessing) 後表示成一維線段的集合。接下來對 每條線段依我們所定義的八種筆劃作抽取動作。對於一細線化之文字，我 們針對某種型態的筆劃，首先找出未抽取的第一個可能線段，作為筆劃開 始線段，並據此找出相鄰線段的組合型態（共有28 種），再根據各種筆 劃組成規則，依次找出連續數個線段所組成的合理路徑（feasible path ），此時，若有數個合理的路徑，則依據一些常識法則找出最佳的一條路 徑，完成這個型態的筆劃抽取。當找出一個筆劃後，將組成的線段從細線 化的文字中刪除並更新刪除線段之相鄰線段的相鄰關係，反覆上述的工作 ，可完成所有筆劃的抽取工作。實驗顯示本方法可在短時間內抽取出正確 的筆劃，並且只有一些多餘筆劃 (Redundant strokes) 存在。 In this thesis, we present a system to extract handwritten Chinese character strokes by using the knowledge of strokes. After the preprocessing an image would be expressed as 1-D set of line segments. There are five strps in the preprocessing: thinning, detection of feature points, extraction of line segments, determination of line segment types, and deletion of short line segments. After preprocessing, we will extract strokes from line segments according to defined eight types of strokes. To extract a specific type of strokes, we first select a starting line segment. Next, we find the possible adjacent line segment of the starting line segment. According to the knowlwdge for the types of strokes, we find a feasible path that consists of continuous line segments. If some feasible paths exist simultaneously, we will apply heuristic knowledge to select the best feasible path. After a stroke is extracted, the line segments of the stroke are deleted. Then, the same procedure for stroke extraction is preformed recursively until no new strokes can be extracted. Experimental results show that we can extract strokes correctly within a short time and exist only a few of redundant strokes.