在以封包為基礎的影像傳輸上，由通道錯誤所造成的封包遺失可能會造成一整張的影像畫面遺失。許多的錯誤還原方法已經被提出以克服通道錯誤，但大多數都只能處理部分已經遺失的巨方塊而對於一整張畫面的遺失卻沒有較佳的解決方案。本論文中，在H.264/AVC的架構下提出一個高效率全畫面錯誤還原的方法。利用動作向量搭配物件的觀念將遺失的畫面像素值還原，對前一張畫面的每一個區塊估計擬真動作向量，並依據估計出來的動作向量將畫面分割成許多個物件。每一個物件會個別依據它的動作向量外插到畫面中相對應的位置，藉以重建所遺失的全畫面。最後，於實驗結果顯示我們的演算法能提供比目前已提出的演算法更好的解決方案，並且更適合人眼視覺上感受。

In packet-based video transmissions, packets loss may result in the loss of the whole video frame due to channel errors. A lot of error concealment algorithms have been proposed to overcome the channel errors, but most of them only can deal with the loss of macroblocks but whole frame. In this thesis, we propose an efficient full frame recovery algorithm which is based on object-based module for a new coding standard H.264/AVC. First, our proposed method estimates the true motion of each block in the reference frame. Besides, the reference frame will divided into several objects according to the estimated motion vectors. Furthermore, each object will be extrapolated to its corresponding place in the missing frame. Finally, the experimental results show that our algorithm could provide a more efficient solution to recover a missing whole frame than previous methods. In addition, based on the object-based module, our proposed method provides the better visual quality than other comparative algorithms.

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