錯誤隱藏是一種常用於視訊傳輸時修補毀損資訊的技術。本論文提出一種結合時間域及空間域的錯誤隱藏架構，此架構對於時間域及空間域各自擁有多種錯誤隱藏方法。透過我們所提出的評分機制，可以決定出最佳的錯誤隱藏方法來修補當前畫面下發生錯誤的區塊。
另外，為了在時間域錯誤隱藏獲得更佳的邊緣對齊效果，以及去除區塊效應所帶來的影響，我們提出一種更精確的移動向量預測法，透過鄰近的區塊來預測錯誤區塊的移動向量。之後，使用預測後的移動向量及我們所提出的失真函數來決定最佳的參考區塊，此參考區塊使用圖形切割演算法來隱藏發生錯誤的區塊。實驗結果顯示無論使用我們所提出的錯誤隱藏架構或是所提出的時間域錯誤隱藏方法，比起其他方法都可以獲得良好的錯誤隱藏結果，以及更佳的修補過後影像。

Error concealment is one of the techniques that have been adopted to recover the corrupted information for video transmission in H.264 standard. In our thesis, we proposed an error concealment structure which combines spatial and temporal error concealment, and each of them has several error concealment methods. Through the proposed score mechanism, we could find out the best error concealment method to conceal the error block in the current frame. Besides, in order to get the better edge alignment and eliminate the block artifact in the temporal error concealment, we proposed a precise method to estimate the motion vector of error block from its neighbor blocks. Then, using this motion vector and proposed distortion function to find the best reference block which uses the graph cut algorithm to conceal. The experiment results show that no matter using the proposed error concealment structure or the proposed temporal error concealment, it provides better concealment result and visual quality than the other methods in our proposed error concealment structure.

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