隨著三維運算技術及其應用迅速的發展，對物件形體之數位化工作的需求與日俱增。目前三維重建系統也被廣泛的應用於電影、醫學、遊戲等各種領域中。本研究利用結構光三維重建系統來重建出物體表面的點雲，在重建前需要校正攝影機和DLP的參數，我們使用OpenCV的校正方法來校正，校正完成後可獲得攝影機與DLP之間的對應關係，即可計算並重建出物體的表面。起初使用格雷碼條紋圖進行重建，格雷碼條紋圖的編碼優點為不易受物體輪廓影響，但經過量測後發現精準度不高，改使用相位移條紋圖進行重建可獲得連續編碼，但容易受物體輪廓影響導致解碼失敗， 最後我們使用混合格雷碼與相位移條紋圖結合兩種條紋圖的優點，格雷碼條紋編出一個區塊的粗編碼，相位移條紋圖可將粗編碼細化產生共多的編碼，此種方式可編出連續且穩定的編碼。

With the rapid development of technology and application of three dimensional surface imaging, increasing demand on the digitization of complex free-form surfaces. Three-dimensional measurement constitutes an important topic in computer vision, having different applications such as film, medical, game and others. Our thesis is use of structured light system to reconstruct a 3D object surface of point cloud. Before reconstruction, DLP and camera parameters need to be calibrated by using OpenCV algorithms. After calibration, we can obtain relationship between DLP and camera. DLP projects patterns onto the surface of the object and decode patterns to obtain the corresponding point between DLP and camera, then it can reconstruct 3D surface of the object.
Initially using gray code patterns to reconstruct 3D object. The advantage of gray code patterns is less influence by the complex 3-D objects, but the accuracy is not high. The use of phase shift patterns for successive encoding, but is easily influence by the complex 3-D objects. Finally we use hybrid patterns that combine gray code and phase shift patterns to reconstruct 3D object. The advantages of hybrid patterns is gray code patterns encode a block code words and phase shift patterns can refine the code word to produce more code words. In this way, we can obtain continuous and stable code word.

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