Instantly Decodable Network Coding for Real-Time Scalable Video Broadcast over Wireless Networks

TL;DR

This paper introduces two prioritized instantly decodable network coding algorithms for real-time scalable video broadcast over wireless networks, improving video quality by optimizing packet delivery before deadlines.

Contribution

The paper develops novel prioritized IDNC algorithms (EW-IDNC and NOW-IDNC) that enhance protection of important video layers and maximize receiver decoding before deadlines.

Findings

EW-IDNC and NOW-IDNC outperform existing algorithms in simulations.

Proposed algorithms increase the number of receivers decoding key video layers.

Simulation results show improved video quality with the new algorithms.

Abstract

In this paper, we study a real-time scalable video broadcast over wireless networks in instantly decodable network coded (IDNC) systems. Such real-time scalable video has a hard deadline and imposes a decoding order on the video layers.We first derive the upper bound on the probability that the individual completion times of all receivers meet the deadline. Using this probability, we design two prioritized IDNC algorithms, namely the expanding window IDNC (EW-IDNC) algorithm and the non-overlapping window IDNC (NOW-IDNC) algorithm. These algorithms provide a high level of protection to the most important video layer before considering additional video layers in coding decisions. Moreover, in these algorithms, we select an appropriate packet combination over a given number of video layers so that these video layers are decoded by the maximum number of receivers before the deadline. We formulate this packet selection problem as a two-stage maximal clique selection problem over an IDNC graph. Simulation results over a real scalable video stream show that our proposed EW-IDNC and NOW-IDNC algorithms improve the received video quality compared to the existing IDNC algorithms.