賴飛羆臺灣大學：資訊工程學研究所羅煜賢Lo, Yu-HsienYu-HsienLo2007-11-262018-07-052007-11-262018-07-052006http://ntur.lib.ntu.edu.tw//handle/246246/54029因為多媒體系統的快速發展，網路數目、裝置種類及編碼格式逐漸增加。因此，在不同編碼系統間的溝通變得更加重要。此外，在網路上傳送資料的過程中，可能會因為網路發生錯誤造成資料流失，如此解碼器便無法成功解碼。在這篇論文中，我們提出一種MPEG2 到H.264 轉換器的架構。並且在此架構中加入Multiple Description 編碼技術，利用此技術即使發生一部份的資料遺失，我們仍然可以將影像成功解碼。在這種架構下，我們可以得到一個壓縮比更好、更有抵抗資料流失能力的檔案。實驗數據顯示出，在與一般轉換器架構比較下，將Multiple Description 編碼技術應用上去使影像資料有抵抗網路錯誤的能力，再以PSNR 作為衡量影像品質的工具，我們也可以得到相當不錯的結果。The development of multimedia systems has a major influence in the area of image and video coding. Therefore, interoperability between different systems become more important. Consider the probability of the data loss when they are transmitted over network. Utilizing the technique of multiple description coding against the data loss is proposed in this thesis. The proposed transcoding architecture incorporates multiple description coding to strengthen the ability of error resistance. Experimental results show that the compressed video data can be decoded successfully and the quality is acceptable when the packet loss occurs. If the error is free, we can get a nearly the same quality measured in PSNR compared to the same transcoder without using the technique of multiple description coding.CHAPTER 1 INTRODUCTION 1 1.1 THE NEW STANDARD H.264/AVC 1 1.2 MOTIVATION 2 CHAPTER 2 RELATED WORK 4 2.1 VIDEO TRANSCODING ARCHITECTURES 4 2.1.1 Drift Error 5 2.1.2 A Simple Bit-rate Reduction Transcoding Architecture 5 2.1.3 A Cascaded Pixel-domain Transcoding Architecture 6 2.1.4 A Simplified Transcoding Architecture 7 2.2 POSTPROCESSING ERROR CONCEALMENT 8 2.2.1 Motion Compensated Temporal Prediction 8 2.2.2 Spatial Domain Interpolation 10 2.3 FORWARD ERROR CONCEALMENT 11 2.3.1 Multilayer Coding 11 2.3.2 Multiple Description Coding 13 CHAPTER 3 PROPOSED SCHEME 20 3.1 DIRECTION-ORIENTED MULTIPLE DESCRIPTION 20 3.1.1 Discussions 20 3.1.2 Direction Decision 21 3.1.3 Direction-Oriented MD Encoder 23 3.1.4 Decode Process 28 3.2 TRANSCODER WITH MULTIPLE DESCRIPTION CODING 34 3.2.1 A Simple Architecture 34 3.2.2 The Issue for Performance Improvement 35 3.2.3 Detailed Description for Refined Architecture 37 CHAPTER 4 EXPERIMENTAL REPORTS 39 4.1 EXPERIMENTAL ENVIRONMENT 39 4.2 EXPERIMENTAL RESULTS 40 4.3 DISCUSSIONS 55 CHAPTER 5 CONCLUSIONS AND FUTURE WORK 57 5.1 CONCLUSIONS 57 5.2 FUTURE WORK 57 Bibliography 581673871 bytesapplication/pdfen-US錯誤處理編碼轉換器transcodermultiple descriptionerror concealmentthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/54029/1/ntu-95-R93922138-1.pdf