本論文中提出一套高效率的人臉識別系統，可以應用到門禁管制、保全監控、互動服務等系統中。此識別系統主要包含人臉偵測以及人臉辨識兩個子系統。
人臉偵測系統中，利用膚色找到人臉的搜尋區域後，再以橢圓樣板演算法，找出可能為人臉的影像，最後以主分量分析（Principal Component Analysis，PCA）確認偵測到的影像是否為人臉影像。
人臉辨識系統中，使用離散小波轉換（Discrete Wavelet Transform，DWT）以及線性鑑別式分析（Linear Discriminate Analysis，LDA）得到具有鑑別性的特徵參數，在測試時以最接近特徵線（Nearest Feature Line，NFL）做為分類法則，建立起一套強健而準確的辨識系統。
實驗結果顯示，在人臉偵測中，偵測正確率為96.2%，所需時間約28ms；在人臉辨識部分，辨識率能達到94.56%，在Pentium M 1.5G中辨識一位成員所需的時間僅需8.37ms。

In this thesis, an efficient face identification system is proposed. The system can be applied to a security monitoring, doorway intercom and interactivity service, etc. The identification system mainly consists of two sub-systems: one is face detection and another is face recognition.
The face detection sub-system detects face search region using skin color information. We detect the possible face images using an ellipse template algorithm, and finally the human face using principal component Analysis (PCA).
For the face recognition sub-system, we can extract the low-dimensional discriminative feature parameter for human faces using the discrete wavelet transform (DWT) and Linear Discriminant Analysis (LDA). Finally, we employ the nearest feature line (NFL) to determine the most likely person. We can construct a robust and high-accuracy recognition system.
The experimental results in face detection part show that the successful rate is 98.4%. For the face recognition part, the recognition rate for a single image reaches 94%. Finally, the computation time of the entire face recognition system is 0.26 seconds on the average, using a Pentium M 1.5G personal computer.

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