本研究係藉由原有的一套以一般光源之非接觸式三次元量測系統進行小物件的三維輪廓的重建。由於量測資料點中含有許多環境所產生的雜訊干擾，故分析雜訊特徵並設法消除雜訊，並找尋最佳參數設定，以得到更佳的三維輪廓重建結果。
本研究利用對焦尋形法來求得待測物之三維輪廓資訊，以重建其原貌。透過Modified-Lapacian(ML)以及Sum-Modified-Laplacian ( SML )運算子可計算出待測物影像在對焦與失焦間的差異，進而得到待測物輪廓之深度變化資訊。而ML運算後加入高斯平滑濾波可以消除影像中不必要之背景雜訊。經由轉換矩陣得到實際三維立體座標資訊，再透過逆向工程軟體重建待測物輪廓及尺寸加以驗證。吾人提出於運算之最後加入中間值法，以得到更平整之輪廓點。藉由部分區域測試與全域影像測試之結果相互驗證，找到最佳之運算法。

Abstract

The shape-from-focus is an economic approach for 3-D measurement. However, the 3-D image reconstructed using this approach generally suffered by relatively high level of noise. In this study, it is of interest to optimize this technique to reach a better result. Modified-Laplacian (ML) operator and Sum-Modified-Laplacian (SML) operator are generally used in this approach to identify object in focus. The study confirmed that the use of SML after ML operator provide a more accurate result. However, using Gaussian filter between ML and SML operator is helpful in removing background noise. Adopting the median method can smooth the contour points and provide a more accurate result.

Key word：Shape-from-focus, Optimization.

參考文獻
[1] 莊峻超, “逆向工程Imageware功能剖析,” 全華科技圖書股份有限公司, 2003.
[2] 范光照, 章明, 姚宏宗, 許智欽, “逆向工程技術及應用,” 高立圖書有限公司, 1999.
[3] 廖克東, “應用機器視覺於低對比動態X-Ray影像強化及瑕疵偵測Classification for Real-Time Dynamic System ),” 私立元智大學工業工程與管理學系碩士論文, 2001.
[4] 田亦凡, “高速超音波影像檢測系統( High Speed Ultrasonic Image Inspection System ),” 國立成功大學機械工程學系碩士論文, 2001.
[5] 劉寶信, “電子構裝三維尺寸之雷射量測( Laser Measure on The Three Dimensional Size of The IC Package ),” 國立成功大學工程科學系專班碩士論文, 2003.
[6] 張振龍, “360度立體快速量測系統與寬頻之應用( 360 Degrees Rapid Measuring System of 3-D Profilometry and Application in Wideband Network Collaboration ),” 國立台灣大學機械工程研究所碩士論文, 2000.
[7] 王彰群, “自製影像式量測儀之自動化研究( The Study of Automation in CCD Camera Measurement Device ),” 國立交通大學機械工程系碩士論文, 2001.
[8] 馮信榮,“二維影像於三維輪廓重建之研究,” 國立台灣大學機械工程研究所碩士論文, 2001.
[9] 周佳彥,”運用雙影像對應求取3D座標資訊-模擬退火法之應用” 朝陽科技大學工業工程與管理所碩士論文, 2003.
[10] Nayar, S. K. and Nakagawa, Y., “Shape from Focus : An Effective Approach for Rough Surfaces,” Proceedings of 1990 IEEE International Conference on Robotics and Automation, vol. 2, May 1990, pp.218-225, Cincinnati, USA.
[11] Ens, J. and Lawrence, P., “An Investigation of Methods for Determining Depth from Focus,” IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 15, No. 2, Feb. 1993, pp.97-108.
[12] Noguchi, M. and Nayar, S.K., “Microscopic Shape from Focus Using Active Illumination,” Proceedings of the 12th IAPR International Conference on Pattern Recognition, Vol. 1, Oct. 1994, pp.147-152, Jerusalem, Israel.
[13] Jähne, B. and Geißler, P., “Depth from Focus with One Image,” Proceedings CVPR '94., IEEE Computer Society Conference on Computer Vision and Pattern Recognition, June 1994, pp.713-717, Seattle, USA.
[14] Subbarao, M. and Choi, T., “Accurate Recovery of Three-Dimensional Shape from Image Focus,” IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 17, No. 3, 1995, pp.266-274.
[15] Ishii, A., “3-D Shape Measurement Using a Focused-Section Method,” Proceedings of 15th International Conference on Pattern Recognition, Vol. 4, Sep. 2000, pp.828-832, Barcelona, Spain.
[16] 蘇俊欽, “以Shape-from-Focus(SFF)和Depth-from-Focus(DFF)為基礎之三次元量測系統( Development of 3-D Measurement System by SFF(Shape-from-Focus) and DFF (Depth-from-Focus) ),” 國立清華大學動力機械工程學系碩士論文, 2004.
[17] Kim, Y. T., “Contrast enhancement using brightness preserving bi-histogram equalization,” IEEE Transactions on Consumer Electronics, Vol. 43, No. 1, pp.1 –8, 1997.
[18] 吳成柯, 戴善榮, 程湘君, 雲立實, “數位影像處理,” 儒林圖書有限公司, 2001.
[19] Jia Li†, James Ze Wang‡, Robert M. Gray§, Gio Wiederhold¶, “Multiresolution Object-of-Interest Detection for Images with Low Depth of Field,” International Conference on Image Analysis and Processing, Sep. 1999, pp.32-37, Venice, Italy.
[20] Alexander H. Slocum, “Precision Machine Design,” Prentice-Hall International, Inc., 1992.
[21] 莊峻超, “逆向工程Imageware功能剖析,” 全華科技圖書股份有限公司, 2003.
[22] 林瑞璋, 王萬強, 陳文賢, “逆向工程軟體Surfacer使用手冊,” 全華科技圖書股份有限公司, 2002.