Video over wireless networks: A brief review

Video transmission over wireless networks faces several challenges, such as time-varying error rate, bandwidth variation and limitation, battery power limitation. This in turn brings out the need for error resilient video transport, low power dissipation and high compression efficiency. Next generation wireless networks are likely to operate on internet technology combined with various access technologies. In order to ensure connection ubiquity together with high bandwidth and mobility, the network architecture should be heterogeneous, rather than homogeneous. Transmission of video over heterogeneous network puts another constraint on the design of codec, that is the scalability (spatial, SNR, temporal scalability) feature. This paper reviews the characteristics that a video codec must have for video transmission over next generation wireless networks. Emerging mobile networks QoS will have a large variation of bandwidth and delay. Adaptive rate control and error recovery are therefore crucial issues for future research.