在很多應用領域中，常需將物體輪廓分割為直線與圓弧線段。主要是因為很多人造之物體(特別是機械加工零件)是由此兩幾何線段所組合而成。本研究即在於發展一圖形轉換系統，將工業相機所拍攝影像之皮革元件輪廓以直線和圓弧來組成。首先，以影像處理技術找出皮革元件之輪廓，利用局部曲率最大值找出輪廓之特徵點，並利用此輪廓點之餘弦角度特性決定候選直線，利用圓弧擬合法找出候選圓弧及相對近似位置。再以最小距離誤差和確認候選線段並確定起點、終點、圓心與半徑等參數值。

In a lot of application fields, it often needs to divide object outline into straight line and arc line.Because of many artificial objects (especially the machine processes spare parts) are combined withthese two geometric lines. The purpose of this research is developing the system with figureconversion. That is to transfer the image acquisition of the leather component outlines into straightline and arc line. The first, find out the leather component outlines by using image processingtechnology, then determine the features of its outline by partial curvature maximum, and use thecosine angle of this outline to decide electable straight line, and then find out electable arc and theopposite approximate position by using arc combination. Finally, confirm minimal range error,electable line, starting point, terminal point, the center of a circle and radius etc.