人臉的表情、姿態、燈光等變化對強健性人臉辨識是極具挑戰的問題。為了克服這些問題，本論文提出一種基於區域特徵之線性迴歸演算法來進行人臉辨識。線性回歸演算法是非常有未來性的人臉辨識方法，但直接以人臉影像強度為特徵則會因人臉的表情、姿態、燈光等變化而產生問題。過去幾年，尺度不變性特徵轉換的區域特徵在影像辨識的應用上備受注目。因為尺度不變性特徵轉換對於影像的尺度變化、旋轉及燈光變化是一種強健的區域特徵，我們引進此種區域特徵加上線性迴歸將可以解決人臉辨識所面臨的問題。本論文我們使用主成份分析來進行降維，然後以線性回歸分類法來完成辨識。實驗結果顯示本文提出的方法相較於類似的方法有更好的表現。

Variations (expression, pose, illumination, and so on) in a face image are the challenging problems for a robust face recognition system. In order to overcome these problems, in this thesis, we proposed a local feature based linear regression classification algorithm for face recognition. Recently, the linear regression classification (LRC), which evolved as a promising method for face recognition, suffers from problems with the variations when we use intensity value directly in the LRC. Over the past few years, the local features such as scale invariant feature transform (SIFT) have been gained much attention for recognition and pattern matching. Since the SIFT is a robust method to defend the different situations with scale, rotation and illumination variations of an image, we expected that the local features instead of pixel information can be more robust to meet the above challenges. Before classifying the features, we reduce the feature dimension with a statistical method, called the principal component analysis (PCA). Finally, linear regression classification (LRC) has been performed on these features. Experimental results show that the proposed method performs better the related methods.

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