Combined Video Coding And Multilevel Modulation

Abstract

A video transmission system based on combined source coding and multilevel modulation is proposed. For the proposed system, graceful degradation for noisy channels is obtained by finding good index maps between the quantized source coder parameters and the amplitude levels of a multilevel QAM signal constellation. The index maps are designed both for good neighbor properties and for power efficient transmission by using simulated annealing. The performance of the proposed system is comparable to a reference system based on the H.263 coder for high CSNR values, and degrades far more gracefully for low CSNR values. 1. INTRODUCTION Recently, there has been much interest in combined source coding and channel coding/modulation for transmission over noisy channels. Some of the work has been focused on binary symmetric channels (BSCs) [1, 2], while other studies have considered amplitude continuous channels [3, 4, 5, 6, 7]. In [1], the index assignment problem was addressed by using simulate..