在影像研究與電腦視覺的領域上，距離轉換是一項重要的技術，利用距離轉換的計算，可萃取出影像的重要特性，如骨幹(skeleton)和物體輪廓(object boundary)等應用上。
在這篇論文中，將比較我們所提出的距離轉換方法與斜切式距離轉換，我們提出的方法將更快又更準確。在computer vision中，物體之邊界分割一直是個基本且重要的課題。本研究使用一套完整的影像處理方法watersnake (距離轉換,分水嶺轉換 and 主動輪廓模式)，使相互接觸之物體影像得以正確分割。經由此方法所處理之物體影像，可依據其個別封閉輪廓線的取得，很容易求得影像中各物體之幾何和紋理，方便應用在醫學影像上。

Euclidean distance transformation is a fundamental technique in image understanding and computer vision. Some important characteristics in image analysis such as skeleton and object boundary are based upon the distance transformation computation.
In this thesis, we compare our method of computing Euclidean distance transformations with the method of Chamfer distance transformation. Our method is faster and more accurate than the Chamfer method. The boundary detection is an interesting and challenging task in computer vision. We integrate distance transform, watershed transform and active contour model to achieve boundary detection. Our method can successfully separate the touching objects, so as to facilitate the subsequent image processing for obtaining the geometric, and texture characteristics of objects. These features are useful for further medical images applications.

中文摘要
英文摘要
誌謝
第一章 序論……………………………………………………1

第二章 距離轉換………………………………………………4
2-1距離轉換之定義………………………………………… 4
2-2 斜切式距離轉換（Chamfer Distance transformation）… 10
2-3 查表法與斜切式距離轉換比較……………………………… 13
2-4 多種距離轉換實驗與分析…………………………………… 16
2-4-1 分析簡介……………………………………………… 16
2-4-2 分析具代表性各種方法……………………………… 19
2-5 實驗與討論…………………………………………………… 25

第三章 邊界分割理論………………………………………………27
3-1 簡介動態輪廓模型………………………………………… 27
3-2分水嶺轉換………………………………………………… 32

第四章 抽取物體輪廓…………………………………………35
4-1 距離轉換相關理論的應用與討論…………………………35
4-2 抽取物體輪廓的程序………………………………………38

第五章 結論………………………………………………………51

參考文獻……………………………………………………………………54

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