在現今時日下，探討影像傳輸在容易發生錯誤的頻道裡是不可或缺的課題。藉由不同的影像壓縮編碼標準，如H.264和MPEG4等使得影像資訊流的大小可以壓縮至以目前的頻寬達到即時撥放的能力。然而，一旦影像資訊封包受到干擾而遺失，則由於編碼時依靠多餘資訊的移除來達到高壓縮率的關係，將造成空間域的錯誤擴散和時間域的錯誤傳遞，使得影像品質大幅下降。為了改善上述錯誤而下降的影像品質，使用錯誤隱藏技術會是一個有利的修正方式。利用壓縮後留下的空間域與時間域的關聯性，解碼端的錯誤隱藏成為不會對網路頻寬以及編碼端產生影響的一個獨立工作。
　　這篇論述主要是基於物件導向觀點，提出一個改良後的空間域錯誤隱藏方法。原始架構參考了多方向性插補法，首先測偵某一個遺失區塊周圍的邊緣分佈情況，透過恢復邊緣可將遺失區塊切割成多個子區塊，再由子區塊個別參考周圍可用資訊，以有方向性的插補法來回復整個遺失區塊。改良的部份修改了切割多重區塊的方法以及插補法的順序，這樣一來既可保有影像修補結果的品質，也縮短了計算所耗費的時間。

The transmission for the video stream over the error-prone channel is the indispensable subject to discuss in nowadays. By the variant video compressed coding standards such as H.264 and MPEG4, the video stream can possess a highly compressed rate to transmit in the real-time display. However, once the packet erasures happened, it may cause severe error propagation during the decoding process. By utilizing the remaining spatial and temporal relativity to reconstruct the corrupted data, an error concealment technique at decoder becomes an individual work that will not affect the bandwidth of networks and the encoders.
The discussion in this thesis is mainly attempted to introduce a refined spatial error concealment method based on the viewpoint of object-oriented manners. The original structure is based on the Multi-directional Interpolation. First of all, the distribution of edges around a lost MB is detected. Through reconstructing the edges, the missing block is then partitioned into several segments. Each segment will be interpolated directionally by available reference pixels around the segment, and at last the whole block can be restored. The proposed method provides a complete process of partitioning and modifies the order of interpolation. Therefore, we can achieve the same quality as recovered by original method while reduce the time for computing.

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