建立好的立體臉部模型是整形外科手術模擬所不可缺少的，這類的手術模擬可以應用在顱顏疾病或咬合不正的疾病；手術模擬重視物體變形的即時性及準確性，而簡化資料量及建立有限元素模型可以達到這些目的。其中陰影造形法是目前重建人臉立體資料的方法中，較安全且較便宜的一個方法。
陰影造形法首先對物體從數個不同的光源位置拍攝相片，再根據照片上的亮度梯度值，從二維的照片重建出物體的立體影像。由Lee 和 Kuo所提出的陰影造形法，其特點是準確度高但是計算時間長且資料量過大，改善他們方法中的三角形網格模型，可以解決這個問題。
我們的研究首先對一人臉從四個不同的光源角度拍攝照片，用Otsu的方法取閥值後，將四個影像聯集，把我們的有興趣的區域選取出來。再來將四張相片的影像做平均，可以得到一個近似光源在正中央的影像。將影像做平滑濾波以後，可以根據亮度梯度值的大小，初步將臉分成三大區塊，再使用形態學的運算子進一步來處理這三大區塊。然後根據每個區塊的亮度梯度值，決定灑點密度後，灑方格點，接下來使用Delaunay三角化法，可以得到人臉網格。

It is important to have a good 3D human face model in plastic surgery simulation. The surgery simulation can be applied on cranial-facial disease or malocclusion. Real-time and accuracy are important goals in developing surgery simulation system. To reduce data set and to build a finite element model can achieve these goals. Shape from shading is cheaper and safer above the methods of reconstruct 3D human face data.
At the beginning shape from shading acquire the image of the object from several light source positions. Next we reconstruct the object’s 3D image from the 2D pictures according the illumination gradient of the pictures. The method of shape from shading proposed by Lee and Kuo has the characteristic of high accuracy but high computation time and huge storage data set. To improve the triangular mesh model in their method can solve the problem.
Our research firstly acquires the face image from four different light source positions. After applying the Otsu’s thresholding method, we continuum the four images to find out the region of interest. Next we average the images of the four pictures; we can get the image that is approximately light source in the central. After smoothing the image, we can set the image into 3 areas based on illumination gradient initially. Then we apply morphological operator to deal with these 3 areas. After this, we determine the nodes distribution density and distribute grid nodes based on the illumination gradient of each area. Next we use Delaunay triangulation to get the mesh of human face.

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