Scalable video coding and transport over broadband wireless networks

Abstract

Abstract| With the emergence of broadband wireless networks and increasing demand of multimedia information on the Internet, wireless multimedia services are foreseen to become widely deployed in the next decade. Real-time video transmission typically has requirements on quality of service QoS. However, wireless channels are unreliable and the channel bandwidth varies with time, which may cause severe degradation to video quality. In addition, for video multicast, the heterogeneity of receivers makes it di cult to achieve e ciency and exibility. To address these issues, three techniques, namely, scalable video coding, network-aware adaptation of end systems, adaptive QoS support from networks, have been developed. This paper uni es the three techniques and presents an adaptive framework, which speci cally addresses video transport over wireless networks. The adaptive framework consists of three basic components: 1 scalable video representations, 2 network-aware end systems, and 3 adaptive services. Under this framework, as wireless channel conditions change, mobile terminals and network elements can scale the video streams and transport the scaled video streams to receivers with a smooth change of perceptual quality. The key advantages of the adaptive framework are: 1 perceptual quality is changed gracefully during periods of QoS uctuations and hando s; and 2 the resources are shared in a fair manner.

Adaptive Combined Scalable Video Coding over MIMO-OFDM Systems using Partial Channel State Infromation

“…To satisfy (a), MIMO-OFDM system can provide broadband services [1] [2]. For (b), the method of scalable video coding (SVC) can divide a bitstream into several sub-bitstreams or layers according to network states, which can offer efficiency and superior quality video coding on broadband services compared to other video coding methods [3] [4]. There are two groups of the bitstream, one is the base-layer bitstream and the other contains some enhancement-layer bitstreams.…”

“…Combination of base-layer and several enhancements-layers in decoder system will produce a high quality video, that is scalable technique of combined scalable video coding (CSVC). When an interruption or error occurs in video transmission, at least the base-layer can be received by the receiver [3].…”

An Improved AIMD Algorithm for Wireless Cellular Video Transmission

“…Actual bandwidth of wireless channels fluctuates due to several factors including mobile terminal moving, the unused resource of a base station to newly joint hosts, multipath fading, cochannel interference, noise disturbances, the changing distance between the base station and the mobile host, and the number of active user. With channel waving, the sending speed should be modulated regularly according to the real-time bandwidth to avoid congestion collapse [2].…”

Error concealment for SNR scalable video coding

“…To address this problem several efforts have been considered to make video bitstreams robust to channel errors. Scalable coding is one of the successful methods of delivering video contents over heterogeneous channels and provides a robust error protection tool [5,3,14].…”