發展成熟的視訊壓縮技術造就了視訊通訊的普及化，然而在通訊媒介中所導致的封包遺失或是位元錯誤是不可避免的，視訊在可能遺失或發生錯誤的頻道中傳遞，接收端即可能取得錯誤的影像。在如H.264/AVC 、MPEG4等高壓縮倍率的視訊編碼技術下，使得視訊可在網路上傳遞，甚至即時地進行網路視訊，然而藉由移除多餘的視訊資訊所達到的高壓縮倍率所帶來的影響，即是空間域的錯誤擴散和時間域的錯誤傳遞之副作用。視訊資料異於檔案資料，少量的錯誤所帶來的影響尚可被接受，但壓縮加劇了傳遞錯誤所造成的影響。為了提高錯誤所造成的影像品質，因此錯誤控制和錯誤修正便能成為有利的修正方式，利用壓縮後留下空間和時間上的相關性，解碼端的錯誤修補成為可能在不造成編碼端和網路上額外的流量負擔之下單獨進行的工作。
本文主要討論的方向為空間域錯誤的隱匿的方法，在適用於區塊式編碼的各種錯誤修補演算法中，對於具有多重邊緣經過之區塊的修復尚有能改善之處，因此於文中提出有效針對多重邊緣進行修復問題的演算法。個別處理遺失的區塊周圍各個邊緣單位，藉此以達到更佳峰值信噪比(PSNR)之重建影像。重建過程中，以改善後計算角度的演算法取得各邊緣單位之向量，以適當的條件評分取得最佳的邊緣連結方式，再以雙向內插修補非邊緣的區域。並在編碼端預測解碼端可能進行的最佳修復形式，再利用資訊隱藏的技術將預測之結果嵌入影像之中，一旦傳輸過程中發生錯誤，解碼端便可在不造成額外的網路流量下取得編碼端的修復資訊有效地進行錯誤修復。

With the ripe development of video compression technique, popularity of the video communication had been brought up. However, the packet loss and the bit error occurred in the communication media is inevitable. Once the video data transmitted over an error-prone channel, it is possible for receiver to retrieve a corrupted video sequence. The coding standards such as H.264/AVC and MPEG4 which have a high compression rate made it possible to transmit video data and even real-time video payload over network .But the influence of error propagation in the time domain and the sequential data loss in spatial domain is also caused as the side effect of this high compression rate. The essence of fault-tolerant in video data made it different from file transmission. A small amount of transmission error is tolerable. However, the compression process aggravates the influence of transmission error. In order to improve the image quality that caused by transmission errors, It is efficient to take use of Error control or error concealment techniques. By using the spatial relativity remained after compression, it is feasible for the decoder to accomplish this job alone without consuming any extra network bandwidth.
The discussion in this text is mainly focuses on error concealment. In the various error concealment algorithms for block-based coding, there is still some works that can be improved for concealment of blocks crossed by multiple edges. We will propose an efficient method for reconstructing multi-edge cases in this paper. By manipulating each edge unit separately, deriving the angle of the gradient for each unit by a similar procedure of directional interpolation, forming the best connection pattern with proper judging criterion, and filling the rest of the region by bilinear interpolation, we reconstruct the broken blocks. Besides, the estimation of the best error concealment algorithm which will be processed in the decoder will be done, in the encoder side. Then we embed the estimated result into the image by data hiding techniques. Once the error appeared during the transmission, the decoder can efficiently conceal the loss by the information embedded by the encoder without incurring extra network payload.

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