使用編碼區塊樣式之多視角視訊快速編碼演算法

Fast Mode Decision for Multi-View Video Coding Based on Coded Block Patterns

劉宇軒(Yu-Shiuan Liou)

指導教授 ： 楊士萱

國立臺北科技大學/電資學院/資訊工程系研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00007

摘要

近年來，多視角視訊越來越受到重視。相較一般單視角視訊，多視角視訊可以讓人們從更多視角觀賞影像，享受到更真實的立體感受，但其資料運算量也相對龐大。多視角視訊編碼(Multi-view Video Coding, MVC)針對多視角視訊進行有效率的壓縮，也是目前H.264/AVC視訊標準正在研發的目標。如何減少MVC龐大的運算量，以適合實際多視角視訊的應用，乃成為一個相當值得探討的課題。在本論文中，我們運用畫面間與畫面內的相關性，來做為快速模式選擇的條件。對於不會參考到視角間畫面的編碼區塊，我們使用全零區塊的條件來判斷最佳區塊模式是否為Direct模式或Inter16x16模式，後續再利用編碼區塊樣式、編碼模式及碼率失真成本的比較，挑選出使用較大區塊做動作估計的模式。對於會參考到視角間畫面的編碼區塊，我們先利用全零區塊的條件決定是否需要參考到視角間畫面，後續再依循不參考視角間畫面的作法進行快速模式選擇。實驗結果顯示我們所提出的方法在不大影響影像品質的前提下，對於各種不同特性的視訊，大約能提升60%~90%的編碼速度。

關鍵字

多視角視訊 ； H.264/AVC ； 編碼區塊樣式 ； 快速模式選擇 ； 參考畫面選擇

並列摘要

Multiview video systems are gaining more attention in recent years. Compared to single-view video, multi-view video provides more view-angles and more realistic 3D experience. Multi-view video coding (MVC), which aims at efficient compression of multi-view data, is an on-going development of the H.264/AVC video coding standard. The huge computational requirement for MVC, however, needs to be resolved before the practical use of MVC. In this thesis, we use the inter-frame and intra-frame correlation for fast mode selection. For macroblocks in non-interview frames, we use the all-zero-block condition to determine the Direct mode and Inter16x16 mode. Coded block patterns, mode and RDcost comparisons are subsequently applied to select the macroblocks with larger matching blocks. For macroblocks in interview frames, the all-zero-block condition is first used to determine whether referencing interview frames is necessary. Subsequent expediting criteria for interview frames are similar to those for non-interview frames. Experimental results show that the proposed method provides 60% to 90% time savings for multi-view videos of various characteristics at the expense of a slight increase in bit rate.

並列關鍵字

multiview video coding (MVC) ； H.264/AVC ； coded block patterns ； fast mode decision ； reference frame selection

參考文獻

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