A Transcoding Architecture for Adapting MPEG-21 Digital Items in Mobile Networks

Due to the vast size, real-time requirement, QoS consideration, etc., of mobile devices, techniques like multimedia transcoding are developed to satisfy the need of surfing the multimedia services using mobile devices. In this paper, we will propose a transcoding proxy architecture for adapting MPEG-21 digital items in mobile networks. Our proposed multimedia proxy system will cover the following concerns: (1) design a system architecture for the proposed multimedia proxy with MPEG-21 digital item adaptation, and (2) develop a cache and replacement policy for adapted MPEG-21 digital items. The proposed transcoding proxy adopts fine-grain cache and replacement algorithms for different multimedia objects and a cache scheme to smooth the delay variations of a cached object during subsequent playbacks.