Unequal error protection for real-time video streaming using expanding window reed-solomon code

Expanding Window FEC is an emerging scheme for robust real-time video streaming over wireless networks, with low latency and reduction of error propagation. In this work, we focus on the problem of Expanding Window FEC redundancy allocation which has not been adequately addressed in current works. We first analyse the error probability of the adopted Expanding Window Reed-Solomon code (EW-RS), and introduce an equivalent error probability to simplify them. Then we are able to formulate the optimal redundancy allocation into a constrained nonlinear optimization problem, where by allocating the redundancy unequally considering the unequal importance of different frames and their dependency based on the expanding window, unequal error protection (UEP) is achieved and the overall distortion is minimized. Moreover, to reduce the computation complexity, a high-efficiency hill-climbing algorithm is developed to obtain the suboptimal allocation. At last, the experimental results demonstrate the effectiveness of both the proposed allocation scheme and solution algorithm.