應用賽局理論之空間域及時間域適應性錯誤隱藏

Adaptive Temporal and Spatial Error Concealment with Game Theory

陳文迪(Wen-Ti Chen)

指導教授 ： 張隆紋

國立清華大學/電機資訊學院/資訊工程學系/碩士(2010年)

摘要

近來，藉由網路來傳輸影像資訊流的相關應用被廣泛的討論。藉由運用最新的壓縮編碼標準如H.264或MPEG4，使得影像資訊流能夠在達到相當高的壓縮率下來進行即時的播放。然而，在容易發生錯誤的頻道中，容易因為封包遺失或延遲，使得傳輸發生錯誤。當影像資訊封包受到干擾而在解碼時產生錯誤，不只會嚴重降低影像品質，也將會造成時間域上的錯誤傳遞。因此，為了在不影響編碼端及網路頻寬的前提下修復這些錯誤資訊，利用影像資訊流經過編碼壓縮後留下的空間域與時間域的關聯性來進行錯誤修補將是有必要的。
本篇論文主要是介紹一個混合了空間域及時間域修補策略的錯誤修補架構，為了在多種策略中動態的選取修補策略來適應影像中不同區域的錯誤狀況，此架構引用了賽局理論的概念來找出最好的修補策略。另外，為了在時間域的錯誤修補上達到較佳的邊緣對齊，我們提出了一個新的邊界匹配誤差的評估法，此法在搜尋參考的動作向量時把邊緣的資訊也納入評估，使得我們可以在參考幀中找到較佳的區塊來進行錯誤修補。文中同時也提出了一個方案來去除可能出現的方塊效應。

關鍵字

H.264 ； 錯誤隱匿 ； 賽局理論

並列摘要

Recently, the application for transmission of the video stream over the network has been widely discussed. Through applying the latest video coding standards such as H.264 or MPEG4, the video stream has reached high compression rate for real time display. However, in the error-prone channel, the transmission error caused by packets lost or delay brings error in the decoding process, which produce not only the decrease of visual quality but also error propagation problem. Therefore, in order to recover the corrupt data without interfere with the encoder side and the bandwidth; the error concealment techniques which utilize the spatial and temporal relativity are necessary.
This paper is going to introduce a temporal and spatial error concealment structure, each side have several concealment strategies. Through game theory, this structure will find out the best concealment strategy to deal with the error circumstance in different image area. In order to reach better edge alignment in temporal error concealment, we proposed a boundary matching error measurement which takes edge information into account in the motion vector searching process, which helps us to choose a better macro block in reference frame. The thesis also proposed a de-blocking scheme to reduce the blocking effect.

並列關鍵字

H.264 ； error concealment ； game theory

參考文獻

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[9] M. J. Osborne, “An Introduction to Game Theory”, ch 1-3, 2004