本論文提出一個應用在H.264/AVC上的高效率的錯誤還原方法，在本論文中利用動作向量搭配物件的觀念將遺失的區塊像素值以及動作向量還原。在H.264解碼的過程中，每一個4x4像素的小區塊(block)都會存入一個動作向量(Motion Vector)，當遇到遺失的區域時，我們將遺失區域周圍的區塊找出來，並且用
周圍區塊的動作向量來找出與前一張畫面中對應的區塊，藉由尋找前一張畫面區塊的動作向量相似且連接的區塊，將動作向量相似且連接在一起的區塊設定為一個物件，利用物件整體移動的特性將物件像素拿來回填遺失區域的像素，同時連同動作向量一併還原。動作向量的還原是有必要的，因為下一個巨方塊的動作向量會使用本方塊之動作向量做為預測值
實驗數據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，而在計算時間方面仍然能保持即時解碼的效率。

In this Thesis, we propose an efficient motion vector recovery algorithm which is based on an object-base module for a new coding standard H.264/AVC. In H.264 decoding time, each 4x4 block has a motion vector. When there is a damage region, it should be recovered. Our proposed method is to find out the neighbor blocks of the damage region. Then we use the motion vectors of neighbor blocks to find out the reference block in the reference frame. If the motion vectors around reference block are similar to each other, we set these blocks as an object. Because the blocks in the same object usually move together, the object would recover to the lost region with the pixel values and motion vectors. It is important to recover the motion vectors, because he motion vector of next block would use the motion vector of this block as predictor.
Experimental results show that our algorithm could provide a more efficient solution than previous methods. By object-base module, it provides comfortable view for human vision. The computation complexity of the proposed algorithm is low and the decoding can be done in real time.

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