Video transport over VANETs: Multi-stream coding with multi-path and network coding

The emerging and promising Vehicular Ad hoc Networks (VANET) are receiving a lot of attention from both industry and academia due to the wide variety of services such as safe navigation support, entertainment and many more. Providing robust and reliable dissemination of data over VANET is the key issue. Due to varying network topology packet loss and delay are very common in such type of networks which severely influence the perceived video quality at receiving end. We need reliable transmission protocols for text data dissemination while the video data can tolerate a certain amount of packet loss. Therefore, we are more interested in robust Scalable Video Coding (SVC) based streaming over VANET for multi-purpose including safe navigation support, because SVC is a very good solution to alleviate the effects of the error-prone channels. In this paper, we propose a robust scheme for SVC-based streaming over an urban VANET with path diversity and network coding. The scheme calculates the quality of all candidate paths based on Grey Relational Analysis (GRA) and then assigns paths to different layers according to their importance. We also select some nearby nodes along the transmission path for recoding their received packets and store them in buffers for unit period of time. These network coded packets can be retransmit to receivers for recovering lost packets.