【摘要】：在無線網(wǎng)絡(luò)以及智能移動設(shè)備快速發(fā)展的推動下，人們對網(wǎng)絡(luò)視頻點播業(yè)務(wù)的需求與日俱增。傳統(tǒng)的流式VOD系統(tǒng)因傳輸協(xié)議限制無法很好地解決防火墻以及NAT穿越問題，而常規(guī)的漸進(jìn)式VOD則缺乏有效服務(wù)質(zhì)量支持。近年HTTP自適應(yīng)VOD技術(shù)的出現(xiàn)吸引了國內(nèi)外的極大關(guān)注，而MPEG-DASH標(biāo)準(zhǔn)的制定解決了此前各項主流技術(shù)方案間互不兼容的問題，成為領(lǐng)域研究熱點。 本文通過研究分析MPEG-DASH標(biāo)準(zhǔn)，設(shè)計并實現(xiàn)了一套適用性強(qiáng)、低耦合以及跨平臺的VOD系統(tǒng)。VOD系統(tǒng)分為服務(wù)器組件、發(fā)布組件以及播放組件三個部分。 服務(wù)器組件負(fù)責(zé)處理媒體點播請求，對媒體內(nèi)容進(jìn)行編碼并管理。為提高任務(wù)并行控制能力，本文設(shè)計了流水線工作模式以處理點播請求，實現(xiàn)靈活易擴(kuò)展的模塊架構(gòu)。而通過引入云存儲服務(wù)，解決了服務(wù)器組件中的海量數(shù)據(jù)存儲問題，在擴(kuò)充系統(tǒng)服務(wù)范圍的同時降低了與各個外部系統(tǒng)的耦合。 發(fā)布組件主要處理媒體數(shù)據(jù)的傳輸工作。組件核心為HTTP服務(wù)器中間件，系統(tǒng)在其基礎(chǔ)上實現(xiàn)了VOD服務(wù)接口以及資源訪問控制，以符合點播環(huán)境需求。 播放組件是DASH媒體的控制核心，負(fù)責(zé)媒體的所有播放邏輯工作。播放組件使用瀏覽器腳本技術(shù)實現(xiàn)，能夠提供優(yōu)秀的跨平臺服務(wù)支持。由于DASH播放器需要特殊的接口支持，系統(tǒng)額外引入了兼容性播放方案，確保VOD服務(wù)能夠正常工作于各類設(shè)備平臺。 論文詳細(xì)闡述了以MPEG-DASH技術(shù)為基礎(chǔ)的VOD系統(tǒng)的設(shè)計與實現(xiàn)，并通過系統(tǒng)功能性測試，驗證了MPEG-DASH技術(shù)在常見網(wǎng)絡(luò)異常環(huán)境下的有效性。最后，本文針對系統(tǒng)目前存在的編碼性能問題進(jìn)行了相關(guān)測試，，探討了編碼速度與編碼質(zhì)量間的相互關(guān)系，通過權(quán)衡速度與質(zhì)量因素以提高系統(tǒng)可用性。
[Abstract]:With the rapid development of wireless network and intelligent mobile devices, the demand for network video-on-demand (VOD) service is increasing day by day. The traditional streaming VOD system can not solve the firewall and NAT traversal problem well because of the limitation of transport protocol, while the conventional progressive VOD lacks effective quality of service support. In recent years, the emergence of HTTP adaptive VOD technology has attracted a great deal of attention at home and abroad, and the formulation of MPEG-DASH standards has solved the problem of incompatibility among the mainstream technical schemes, and has become a research hotspot in the field. Through the research and analysis of MPEG-DASH standard, a set of VOD system with strong applicability, low coupling and cross-platform is designed and implemented. VOD system is divided into three parts: server component, publishing component and playback component. Server components are responsible for processing media-on-demand requests, encoding and managing media content. In order to improve the ability of parallel control of tasks, a pipelining mode is designed to handle on-demand requests, and a flexible and easy-to-expand module architecture is implemented. Through the introduction of cloud storage service, the problem of massive data storage in server components is solved, and the coupling with each external system is reduced while extending the service scope of the system. The publishing component mainly deals with the transmission of media data. The core of the component is HTTP server middleware, based on which the VOD service interface and resource access control are implemented to meet the requirements of the on-demand environment. The playback component is the control core of DASH media, which is responsible for all the playback logic of the media. Playback component using browser script technology, can provide excellent cross-platform service support. Since the DASH player needs special interface support, the system introduces an additional compatibility play scheme to ensure that the VOD service can work properly on all kinds of device platforms. In this paper, the design and implementation of VOD system based on MPEG-DASH technology are described in detail, and the effectiveness of MPEG-DASH technology in common network anomaly environment is verified by functional testing of the system. Finally, this paper tests the coding performance of the system, discusses the relationship between the coding speed and the coding quality, and improves the system usability by balancing the speed and the quality factors.
【學(xué)位授予單位】：華南理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TN948.64

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 周小兵,廖建明,伍曉東;VoIP通訊中防火墻和NAT問題的解決[J];福建電腦;2004年01期

2 何俊;田應(yīng)洪;洪志良;;基于H.264的熵編碼結(jié)構(gòu)[J];計算機(jī)工程;2008年06期

3 黃健;張琳;;H.264視頻編碼技術(shù)研究[J];計算機(jī)與數(shù)字工程;2006年07期

4 趙永屹;宿紅毅;胡韶輝;;基于AJAX與J2EE的新型Web應(yīng)用的設(shè)計與實現(xiàn)[J];計算機(jī)工程與設(shè)計;2007年01期

5 劉華星;楊庚;;HTML5——下一代Web開發(fā)標(biāo)準(zhǔn)研究[J];計算機(jī)技術(shù)與發(fā)展;2011年08期

6 周繼茂;視頻點播技術(shù)綜述[J];有線電視技術(shù);2004年19期

7 郭曉霞;王磊;李學(xué)偉;姚穎穎;;動態(tài)自適應(yīng)流媒體切片技術(shù)分析[J];有線電視技術(shù);2013年12期

本文編號：2438541