針對頻寬適應功能之可調式多視角視訊串流系統晶片設計

ASIC Design of Bandwidth Adaptation for Scalable Multi-view Video Streaming System

梁耿誌(Keng-Chih Liang)

指導教授 ： 朱元三

國立中正大學/工學院/電機工程學系/碩士(2013年)

摘要

在多媒體的發展與網路應用的快速成長，使得網路多媒體應用成為現代人所使用的一種應用，而由於影像資料量的大幅提升，影像傳輸時所需的頻寬也相應增加。然而頻寬的變化、影像資料量的變化，都會對傳輸造成影響。當頻寬變動時，往往造成畫面的延遲或遺失，導致視訊品質不佳，頻寬使用率下降。H.264/SVC視訊壓縮編解碼格式雖然具有多層編碼的特性，提供空間、時間、品質三種可調式，但其主要只針對單視角影像，若延伸至多視角影像，會有編碼效率、解碼次數、頻寬分配的問題。H.264/MVC視訊壓縮編解碼格式能夠有效壓縮多視角影像，只需一次解碼即可得到所有視角影像，並且提供視角可調式，但是相較於SVC，MVC缺少了空間、時間、品質三種可調式，對於網路頻寬不穩定變動的適應性差。
　　本系統應用H.264/MVC當視訊壓縮格式，可以支援單視角、多視角視訊服務，並加入可調式視訊編碼，針對品質可調式增加多視角視訊編碼的頻寬適應性。並透過頻寬適應策略則提高本系統之網路頻寬適應性，有效利用有限的可用頻寬，提供較好的觀看品質。實驗證明，當在本系統模擬之頻寬不足的情況下，若是加入空間、時間、品質三種可調式進行模擬，本論文提出之策略都可以提供90%以上的頻寬使用率。然而若是調整解析度，影像畫面大小會因可用頻寬不同而頻繁跳動，影響使用者的觀看品質，故我們取消空間可調式，在固定解析度下進行模擬，提出之策略仍可以提供80%以上的頻寬使用率且影像平均PSNR為34 dB。
　　另外，本論文對其中的串流擷取器部分，做成硬體，以降低中央處理器於多媒體傳輸時造成的負擔，形成完整的視訊傳輸高畫質系統。該位元串流擷取器速率可達191.5MHz，面積為0.321578mm2。

關鍵字

多視角視訊編碼 ； 可調式視訊編碼 ； 頻寬適應

並列摘要

With the development of the Internet and the increasingly popular of the multimedia streaming services, the amount of data of video are significantly increasing .The bandwidth to transfer video data also have to increase. The changes of bandwidth and video data will effect transmission. When bandwidth is not insufficient, it may result in delay and loss screen because video data can't be immediately sent to the client. When the bandwidth is sufficient, if the default is too small amount of data transferred, it will result in poor video quality and bandwidth utilization decreased. Although H.264/SVC has the characteristics of the multi-layer coding and provides spatial, temporal and quality scalability, it focuses on single view video and has the question of compression ratio, decoding times and bandwidth allocation extended to multi-view video. H.264/MVC compresses multi-view video efficiently, can get all of view video by decoding once, and provides view scalability. Compares with H.264/SVC, H.264/MVC lacks spatial, temporal and quality scalability and has poor adaptability to unstable changes of network bandwidth. The paper uses multi-view video coding, supports single-view and multi-view video service and joins quality scalability to increase the bandwidth adaptability. Through the paper proposes improve the bandwidth adaptability of scalable multi-view video streaming extractor, increases bandwidth utilization and provides better viewing quality. Experiments show that, when the bandwidth is insufficient, it provides more than 80% of bandwidth utilization and the average PSNR of Ballroom is beyond 34dB.The system also achieved hardware design .The highest frequency of our system will be reached 191.5MHz and coverage area will be 0.543573 mm2.

並列關鍵字

bandwidth adaptation ； H.264/MVC ； H.264/SVC

參考文獻

[3] Gurler, C.G. et al., Flexible Transport of 3D Video over Networks, Journal of Proceedings of IEEE, Vol. 99, No. 4, pp. 694 -707, April 2011.

[6] Heiko Schwarz, Detlev Marpe, and Thomas Wiegand, “Overview of the Scalable H.264/MPEG4-AVC Extension”, IEEE International Conference on Image Processing, Atlanta, GA Oct. 2006.

[7] RTP Payload Format for Scalable Video Coding

[8] MVC/SVC Storage Format

[9]A. Vetro, T. Wiegand, and G. Sullivan, “Overview of the stereo and multiview video coding extensions of the H.264/MPEG-4 AVC standard,” Proc. IEEE, vol. 99, no. 4, pp. 694–707, Apr. 2011.