Video-aware opportunistic network coding over wireless networks

Abstract

Abstract-In this paper, we study video streaming over wireless networks with network coding capabilities. We build upon recent work, which demonstrated that network coding can increase throughput over a broadcast medium, by mixing packets from different flows into a single packet, thus increasing the information content per transmission. Our key insight is that, when the transmitted flows are video streams, network codes should be selected so as to maximize not only the network throughput but also the video quality. We propose video-aware opportunistic network coding schemes that take into account both the decodability of network codes by several receivers and the importance and deadlines of video packets. Simulation results show that our schemes significantly improve both video quality and throughput. This work is a first step towards content-aware network coding.

Instantly decodable network coding for real-time scalable video broadcast over wireless networks

“…This allows immediate decoding of received packets of different video sequences and immediate use of decoded packets at the applications, especially when one or more video sequences are encoded using, for example, multiple description coding in addition to scalable video coding. Such benefits of using IDNC in multiple unicast services was shown in [8,34,35].…”

“…Network coding has shown great potential to improve throughput, delay, and quality of services in wireless networks [1][2][3][4][5][6][7][8][9][10]. These merits of network coding make it an attractive candidate for multimedia applications [7][8][9].…”

“…These merits of network coding make it an attractive candidate for multimedia applications [7][8][9]. In this paper, we are interested in utilizing network coding in real-time scalable video applications [11,12], which compress video frames in the form of one base layer and several enhancement layers.…”

“…Furthermore, the encoding process of IDNC is performed using simple XOR operations compared to the more complicated operations over large Galois fields performed in RLNC. The decoding process of IDNC is also performed using XOR operations, which is suitable for implementation in simple and costefficient receivers, compared to complex matrix inversion performed in RLNC [1,8].…”

“…Moreover, as video streaming applications continue to proliferate, the wireless sender often needs to support multiple simultaneously running applications with heterogenous video characteristics. It is well understood that mixing different video sequences can improve video quality in wireless networks [8,35]. Therefore, the sender can adopt IDNC to encode packets from different video sequences together.…”