Video Transcoding Architectures for Universal Multimedia Service over Heterogeneous Environments

Abstract

Video communication requires the seamless delivery of video contents to a broad range of users with different bandwidth constraints. Transcoding is an essential technique for real-time video communications and VOD (video on demand) services over heterogeneous networks which may require different QoS (quality of service). In addition to the heterogeneity of present communication networks, the heterogeneity of the terminal capability for visual quality makes it even more important to design efficient transcoding algorithms. Furthermore, the video compression standards used by the source signal and the client device may not be the same. For those heterogeneous environments, there have been a lot of research activities in video transcoding including bit-rate down conversion, spatial-resolution down conversion, format conversion, and video composition. This paper gives recent advances we achieved and an overview of research activities in video transcoding for video services over heterogeneous environments.