Error Protection
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Submission Guidelines Research Article Open Access Unequal Error Protection Techniques Based on Wyner-Ziv CodingLiangLiang1, PaulSalama2 and EdwardJ.Delp1Email authorEURASIP Journal on Image and Video Processing20092009:474689DOI: 10.1155/2009/474689© Liang Liang et al.2009Received: 31May2008Accepted: 17March2009Published: 7June2009 AbstractCompressed video is very performance analysis unequal error protection sensitive to channel errors. A few bit losses can stop the entire decoding process. windows protection error Therefore, protecting compressed video is always necessary for reliable visual communications. Utilizing unequal error protection schemes that assign different protection levels
Channel Coding Unequal Error Protection
to the different elements in a compressed video stream is an efficient and effective way to combat channel errors. Three such schemes, based on Wyner-Ziv coding, are described herein. These schemes independently provide different protection
Protection Error I Virtual Dj
levels to motion information and the transform coefficients produced by an H.264/AVC encoder. One method adapts the protection levels to the content of each frame, while another utilizes feedback regarding the latest channel packet loss rate to adjust the protection levels. All three methods demonstrate superior error resilience to using equal error protection in the face of packet losses. 1. IntroductionChannel errors can result in serious loss of decoded video quality. protection error 103 Many error resilience and concealment schemes have been proposed [1]. However, when large errors occur, most of the proposed techniques are not sufficient enough to recover the loss. In recent years, error resilience approaches employing Wyner-Ziv lossy coding theory [2] have been developed and have resulted in improvement in the visual quality of the decoded frames [3–13]. Other works applied distributed source coding onto error resilience include [14–17].In 1976, Wyner and Ziv proved that when the side information is only known to the decoder, the minimum required source coding rate will be greater or equal to the rate when the side information is available at both encoder and decoder (see Figure 1). Denoting the source data by and the side information by , where and are correlated, but the side information is only available at the decoder, the decoder manages to reconstruct a version of , , subject to the constraint that at most a distortion is incurred. It was shown that [2], where is the data rate used when the side information is only available to the decoder and represents the data rate required when the side information is available at both the encoder and the decoder. Figu
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