  There is nowadays a growing demand in vehicular communications for real-time
applications requiring video assistance. The new state-of-the-art
high-efficiency video coding (HEVC) standard is very promising for real-time
video streaming. It offers high coding efficiency, as well as dedicated low
delay coding structures. Among these, the all intra (AI) coding structure
guarantees minimal coding time at the expense of higher video bitrates, which
therefore penalizes transmission performances. In this work, we propose an
original cross-layer system in order to enhance received video quality in
vehicular communications. The system is low complex and relies on a multiple
description coding (MDC) approach. It is based on an adaptive mapping mechanism
applied at the IEEE 802.11p standard medium access control (MAC) layer.
Simulation results in a realistic vehicular environment demonstrate that for
low delay video communications, the proposed method provides significant video
quality improvements on the receiver side.
