在本篇論文中，我們提出了一個具有權重的區域方向性描述紋理方法並應用於臉部表情辨識。我們將臉部影像切割成若干區塊，利用方向性資訊來計算微小樣式的結構，將各區塊微小樣式結構的分佈以權重的概念來表示表情的紋理結構特徵，搭配邊緣偵測後的水平投影來輔助判斷，最終利用支持向量機來做臉部表情辨識。我們一共使用三個資料庫來進行臉部表情辨識實驗。JAFFE 資料庫和Cohn-Kanade 資料庫，各包括七種表情，分別為中性表情、開心、傷心、驚訝、害怕、生氣和厭惡。另外我們也使用CMU-PIE 資料庫，其中包括了中性表情和微笑共兩種表情。由實驗結果可以看出，本篇提出的方法得到的結果較其他方法好。

In this thesis, a weighted local directional texture descriptor is proposed which is applied in facial expression recognition. We partition the face images into several regions, calculate the distribution of the structure of micro patterns using the directional information for each region to represent the facial texture feature with the concept of weight, and the horizontal projection of the result of edge detection is also used to help identify facial expression. Finally, SVM (support vector machine) is used to classify the facial expression. We use three databases to test the performance of the proposed facial expression recognition system. There are seven expressions in both JAFFE database and Cohn-Kanade database, which are neutral, happiness, sadness, surprise, fear, anger, and disgust. For CMU-PIE database, there are two expressions,
which are neutral and smiling. As the experimental result, the proposed method outperforms the other methods in facial expression recognition.

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