（北方工業大學信息工程學院，北京市，100041）
摘要：在基于3G網絡的多媒體調度系統中，為了提高視頻數據傳輸的實時性和可靠性，提出一種視頻流碼率自適應調整算法。通過改進Pathload 算法，利用視頻數據包的單向延時來估計網絡有效帶寬，根據網絡有效帶寬與視頻發送速率之間的大小關系自適應地調整視頻流碼率。在多媒體調度系統上進行了實驗驗證，結果表明，該算法可以比較準確地估計網絡有效帶寬，有效地改善了視頻數據傳輸的實時性并提高了接收端的視頻數據解碼質量。
關鍵詞：信號與信息處理；調度系統；自適應編碼；網絡帶寬估計
An Algorithm of Video Stream Rate Adaptive Control
PENG Kai
(Information Engineering Institute of North China University of Technology, Beijing, 100144, China)
【Abstract】In multimedia scheduling system based on 3G networks, In order to improve the timeliness and reliability of video data transmission, Propose an algorithm of video stream rate adaptive control. Estimate the effective bandwidth of the network by one-way delay of video p -ackets, Adaptive control the video stream rate by compare effective bandwidth of network and video transmission rate. Experiment on multimedia scheduling system, Results show the algorithm could estimate effective bandwidth of network accurately, Improve the real-time of video data tra- nsmission effectively and Improve the quality of Decoded video data.
【Key words】Signal and Information Processing; Scheduling system; Adaptive coding; Estimate the bandwidth of network

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作者簡介：
彭鍇（1990.1.13），男，碩士，視頻編碼與傳輸