近來影像技術因電腦效能的提昇，其運用越來越廣泛，尤其以視訊會議系統、人臉辨識、機械視覺多有研究，本論文特以影像處理技術搭配動態攝影機作臉部追蹤的研究。
在以往的相關研究中多以靜止的攝影機和固定的背景來做追蹤。而我們的研究，是改以動態的攝影機來做人臉的追蹤，並以影像作為系統的回授，修正攝影機的位置。在處理過程中，我們使用膚色(Skin-Color)將人臉從複雜的背景中分離出來，再配合數位影像處理的技巧，找出人臉的所在區域。最後以簡單而快速的橢圓形頭部追蹤演算法，找出人臉的位置，並以此位置來控制馬達的轉動。轉動時，我們設定馬達的轉動機制，讓攝影機所擷取的畫面能更加穩定。目標若超出範圍或消失，馬達將自動的轉回起始位置重新追蹤。使用動態的攝影機追蹤移動中的人臉，目的在於增加攝影機的可視角度，使移動的人臉始終維持在影像的中心位置。

Recently, the technology of image process is greatly improved owing to the high upgrade of computers. The technology can be applied in a variety of applications, such as teleconference, the face recognition and machine vision. For this reason, we study the human face tracking with active camera.
The early relevant researches are limited to static camera and stationary background. In our study, we trace by active camera the human face, as well as the face position in the image which served as the feedback control to revolve motors guiding the camera to correct position. In the process, we use the technology of Skin-Color analysis to segment the human face from complicated background and we also use the technology of digital image processing to find the region of the human face. In the end, we use a simple algorithm to trace the human face by elliptical head tracker to find the position of the face and then to control the motor. We set the rules of motor control in order to stabilize the frames taken by the camera. If the target goes beyond the scope of tracing range or misses from the frame, the motors will turn round to default position and restart the tracing. For the purpose of increasing the angle of view, the active camera is used to trace the moving human face, so that the moving human face always stays around the center of images.

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