Abstract: Taking into account that the network bandwidth has limitation, instability and "making the best" service, it proposes a novel adaptive transmission scheme named GAIMD_Buffer to ensure QoS of video transmission. Based on GAIMD algorithm, the scheme introduces a buffer control strategy of H.264 video streaming for both servers and clients. When the network is in a stable or congested state, and the estimated value of the buffer occupancy is within the given threshold in the next RTT as well, the speed of transmission is adjusted by GAIMD algorithm; otherwise, the stability of the buffer can only be ensured by adjusting the video code rate, which ensures the buffer will not overflow or underflow. Experimental results demonstrate that the proposed scheme works well in the embedded system, which shows more effective smooth jitter, less packet loss and play latency, and improves video quality accordingly.

Key words: H. 264 video; quality of service(QoS); buffer-driven; adaptive