利用SCTP之可調式多視角影像串流頻寬適應系統

Adaptive Bandwidth System with SCTP for Scalable Multi-view Video Streaming

劉哲安(Chen-An Liu)

指導教授 ： 朱元三

國立中正大學/工學院/電機工程學系/碩士(2014年)

摘要

於影像技術的發展，3D視訊以及環景視訊等新技術所產生出來的資料量較以前的影像有著更大的資料量，因此在傳輸影像時候的網路頻寬也必須提高，但網路頻寬有限，在頻寬不足夠時可能會無法即時傳輸到客戶端或是造成封包遺失等狀況，在頻寬足夠時若設定過低的影像品質又會造成觀看品質不佳。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，但其只針對單視角影像，應用在多視角影像時，會有編碼效率差、需多次解碼等問題。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，但由於缺乏空間、時間、品質三種可調性，當頻寬不穩變動時適應性差。SCTP傳輸協定擁有多重連線、多串流、部分可靠的特性，多串流特性可將I、P、B frame分不同邏輯通道傳輸並設立不同的生命週期，讓過期的影像不再重傳。另外目前手機或筆電皆擁有兩張網卡，可以利用來建立多重連線機制，在主要線路失效時，利用SCTP的特性可迅速切換至備用通道。本論文利用H.264/MVC為基礎，加入H.264/SVC的概念，新增時間、品質、空間可調性。並提出頻寬適應策略，讓多視角視訊擁有頻寬適應性，再利用SCTP傳輸協定建立多重連線、多串流等特性，降低傳輸時間，讓過期的影像不再重傳，在連線通道中斷時利用備用通道傳輸。透過實驗證明本論文提出的策略不管在多少的頻寬，均可以使整部影片PSNR在33.8dB以上，並在連線中斷時不中斷使用者觀看影片。

關鍵字

頻寬適應 ； 多視角視訊編碼 ； 可調式視訊編碼 ； 流控制傳輸協議

並列摘要

Due to the development of image technology, the amount of data of High-definition 2D video, full view video, and 3D video are more than traditional video, the bandwidth to transfer video data also have to increase. However bandwidth is limited .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. 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. Compares with H.264/SVC, H.264/MVC lacks spatial, temporal and quality scalability and has poor adaptability to unstable changes of network bandwidth. SCTP protocol has multi-homing、multi-streaming、partial-reliable three characteristic. Using multi-streaming separate I、P、B frame to different logic channel. Set different lifetime to different logic channel. Smart phone and notebook have tow network card nowadays .We can use this characteristic to establish multi-homing improve the quality of video. The system in this paper is based on multi-view video coding, and joins temporal and quality scalability in scalable video coding, improves the bandwidth adaptability of multi-view video streaming. SCTP establish multi-homing that we can use the backup channel when the primary channel is disconnect. Experiments show that, it provides more than 33.8dB of PSNR and doesn’t influence user watching fluency when the primary channel disconnect.

並列關鍵字

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

參考文獻

[3]RFC 4906: Stream Control Transmission Protoco. http://tools.ietf.org/html/rfc4960

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[7] 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.

[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.