EURASIP Journal on Applied Signal Processing 
Volume 2006 (2006), Article ID 85870, 8 pages
doi:10.1155/ASP/2006/85870

H.264 Layered Coded Video over Wireless Networks: Channel Coding and Modulation Constraints

M. M. Ghandi, B. Barmada, E. V. Jones, and M. Ghanbari

 Department of Electronic Systems Engineering, University of Essex, Wivenhoe Park CO4 3SQ, Colchester, UK
Received 13 July 2005; Revised 16 December 2005; Accepted 18 February 2006

Abstract

This paper considers the prioritised transmission of H.264 layered coded video over wireless channels. For appropriate protection of video data, methods such as prioritised forward error correction coding (FEC) or hierarchical quadrature amplitude modulation (HQAM) can be employed, but each imposes system constraints. FEC provides good protection but at the price of a high overhead and complexity. HQAM is less complex and does not introduce any overhead, but permits only fixed data ratios between the priority layers. Such constraints are analysed and practical solutions are proposed for layered transmission of data-partitioned and SNR-scalable coded video where combinations of HQAM and FEC are used to exploit the advantages of both coding methods. Simulation results show that the flexibility of SNR scalability and absence of picture drift imply that SNR scalability as modelled is superior to data partitioning in such applications.