%0 Journal Article
%T Application Layer Systematic Network Coding for Sliced H.264/AVC Video Streaming
%A Sajid Nazir
%A Vladimir Stankovi£¿
%A Ivan Andonovi£¿
%A Dejan Vukobratovi£¿
%J Advances in Multimedia
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/916715
%X Application Layer Forward Error Correction (AL-FEC) with rateless codes can be applied to protect the video data over lossy channels. Expanding Window Random Linear Codes (EW RLCs) are a flexible unequal error protection fountain coding scheme which can provide prioritized data transmission. In this paper, we propose a system that exploits systematic EW RLC for H.264/Advanced Video Coding (AVC) slice-partitioned data. The system prioritizes slices based on their PSNR contribution to reconstruction as well as temporal significance. Simulation results demonstrate usefulness of using relative slice priority with systematic codes for multimedia broadcast applications. 1. Introduction H.264 Advanced Video Coding (AVC) [1] is currently the most commonly used video coding standard, which is gaining widespread use in the emerging communication standards and applications. Two key challenges of multimedia communication applications over wireless networks are high and varying error characteristics of underlying communications channels and huge heterogeneity of users¡¯ equipment. One of the solutions is to use channel coding techniques which could recover the original data despite losses. The latest state-of-the-art solutions like those based on Reed Solomon (RS) codes are inflexible because the code rate has to be fixed in advance. Moreover, the encoding and decoding operations are quite complex especially for large Galois Field. For such codes, the error characteristics of the channel must be known in advance in order to adjust the code rate to it. This solution does not extend well to multiple receivers as then only a worst-case erasure channel can be assumed for all receivers. To enable communications in the presence of packet losses, rateless Digital Fountain Raptor codes [2] have become standardized solution in many wireless systems such as Digital Video Broadcasting-Handheld (DVB-H) [3¨C5], Multimedia Broadcast Multicast Service (MBMS), and mobile Worldwide Interoperability for Microwave Access (WiMax) [6]. Another class of rateless codes which have been gaining increased popularity for applications in wireless broadcast/cellular networks are Random Linear Codes (RLCs) [7, 8]. RLCs show near-capacity performance over erasure channels even for low codeword lengths [9, 10]. In addition, the emerging networking concepts, such as hybrid broadcast/cellular networks (with users equipped with multiple interfaces) or device-to-device communications, offer a number of opportunities for achieving network coding gains using RLC [11]. Traditional solutions for reliable
%U http://www.hindawi.com/journals/am/2012/916715/