Cross-layer design for multimedia delivery over wireless networks

Video summarization has gained increased popularity in the emerging multimedia and communications applications. However, very limited work has been conducted to address the transmission problem of video summary frames. In this paper, we propose a cross-layer optimization framework for delivering video summaries over wireless networks. Within a rate-distortion theoretical framework, the source coding, allowable retransmission, and adaptive modulation and coding have been jointly optimized, which reflects the joint selection of parameters in physical, data link and application layers. The goal here is to achieve the best video quality and content coverage from the received summary frames as well as meet the delay constraint. In this paper, this problem is formulated and solved by using Lagrangian relaxation and dynamic programming. Simulation results indicate the effectiveness and efficiency of the proposed optimization framework, especially when the delay budget imposed by the upper layer applications is small, where more than 12% distortion gain can be achieved.