目前視訊的研究與發展帶來許多新的限制與需求。當場景包含數個不同位置與深度的物體時，針對特定物體進行對焦是必要的。因此，本研究旨在研製一套自動對焦視訊系統，以自製對焦平台為基礎，包含對焦機構、控制電路、個人電腦以及Web Camera，由Web Camera鏡頭獲取影像經由電腦端所撰寫對焦演算法運算，判斷影像清晰度，透過對焦平台調整鏡頭與對焦物之距離，直到獲取清晰影像為止。當對焦物移動或改變時，則會自動重新對焦以獲取清晰之影像。經由實驗結果證實此本研究之自動對焦視訊系統能快速並準確地呈現清晰之影像達到自動對焦的效果。

Since the current progress of video research has brought about new requirements and constraints in the field of image processing. Particular applications need means for performing measurement on images. The focusing of view-finding lenses is critical when scenes contain several objects situated at different depths of field and different positions. Therefore, the goal of this study is developed an automatic focus system for video communication. This system consists of a focusing mechanism, a control circuit, a personal computer and a web camera. Base on the focusing platform, the clear video can be presented with the regulable focal distance even though the focusing objective moved. Practically, this system can focus on the objective rapidly and accurately as well as provide efficiency for the basic of media communication.

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