Energy-efficient co-scheduling of receiving packets and decoding tasks on mobile video streaming terminals

An energy-efficient co-scheduling policy for packet receiving and video decoding tasks is proposed for a mobile terminal receiving video streaming packets from a access point(AP) in a WLAN. Through analyzing the interaction between the network interface card(NIC) and the CPU, a frame buffer between the NIC and the CPU is set to facilitate the cooperation of video packet receiving and video decoding tasks. Based on monitoring the fullness of the frame buffer, the NIC can dynamically adjust its operating mode so as to receive data packets in bursts at the optimal wireless channel state; accordingly, the CPU can also dynamically adjust its operating frequency as lowly as possible to reduce the energy consumption while meeting the deadline of a video frame. This co-scheduling scheme makes full use of the cooperativity between video packet receiving and decoding tasks in a dynamic environment where the computational complexity of the video decoding varies with the video scene changing and wireless network communication bandwidth also varies with time. The experimental results show that it can achieve 30%-35% energy saving for video streaming applications.