人臉偵測最近幾年來迅速地受到大家的重視，並且廣泛地應用在各種領域，諸如『人臉辨識』、『視訊會議』、『數位監控系統』、『智慧家庭系統』、『智慧型人機介面』等等。此類的應用程式之首要工作即是找出是否有人臉存在，並找出其所在之區域。換句話說，一個可靠且快速的人臉偵測法是相當重要的。
本篇文章提出一個簡單且有效的方法來偵測人臉的位置，由於複雜的背景嚴重影響到人臉偵測的成果。我們首先使用膚色分割和連通成分的方法找出人臉候選區、再使用色彩分析的方法從人臉候選區中去尋找臉部特徵(眼睛、嘴唇)。使用色彩的資訊可以減少檢測時間，不過在不同的光線下會有誤判的情況產生，所以我們用自適性的閥值來找出臉部特徵，針對不同的影像用不同閥值去做判斷，最後利用眼睛和嘴唇的幾何關係找到正確的人臉位置。
我們的實驗證明本論文所提出的方法確實可行且可靠，在少許的條件限制下，對於環境採光變化、不同大小之人臉、及複雜背景等問題都可以有效的處理。除了在臉部特徵被遮蔽的情況下會有偵測不到的狀況，其他情況均有良好的偵測率。

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其他參考資料
Rafael C. Gonzalez,Richard E. Woods “Digital Image Processing ”台灣培生教育出版股份有限公司，2003
COULEUR.ORG，http://www.couleur.org/。
人體計測資料庫，http://www.iosh.gov.tw/ergo.htm。
文獻[26]的執行檔，http://www.iis.fhg.de/bv/biometrie/download/index.html。
文獻[27]的執行檔，http://www.geocities.com/fritzfra2001/。