Telecommun Syst (2015) 59:357–363
DOI 10.1007/s11235-014-9941-0
Robust FMO algorithm and adaptive redundant slice allocation
for wireless video transmission
Feng Zhu · Weiming Zhang · Nenghai Yu ·
Xianfeng Zhao
Published online: 27 March 2015
© Springer Science+Business Media New York 2015
Abstract Visual quality of compressed video may suffer
great degradation when transmitted over lossy wireless net-
works. Flexible macro-block ordering (FMO) is a new error
resilient tool adopted by H.264/AVC. It has a good perfor-
mance of error resilience by changing the coding order of
macro-blocks in the frame. redundant slice (RS) is another
tool which adds redundant copy of slices into the stream to
take precautions against packet loss. However, we shouldn’t
only care about peak signal to noise ratio (PSNR) of the
video; the robustness of video streams to burst packet loss of
wireless channel is also worth considering. In applications,
such as real-time video transmission services, degradation of
video quality may be tolerable, but collapse of decoder due to
burst packet loss will greatly lower user’s quality of experi-
ence. This paper proposes a robust FMO (RFMO) algorithm
which takes gradient feature of frames into consideration to
enhance robustness of video streams, and the adaptive RS
allocation (ARSA) helps to increase the PSNR with only a
little increase in bit rate. Experiment results show that the
RFMO algorithm can significantly reduce the collapse times
of decoder with invisible decrease in visual quality, and the
F. Zhu · W. Zhang · N. Yu (
B
)
Department of Electronic Engineering and Information Science,
University of Science and Technology of China,
Hefei, Anhui, China
e-mail: ynh@ustc.edu.cn
F. Zhu
e-mail: zhufengx@mail.ustc.edu.cn
W. Zh ang
e-mail: weimingzhang@yahoo.cn
X. Zhao
State Key Laboratory of Information Security (SKLOIS),
Institute of Information Engineering, CAS, Beijing, China
e-mail: zhaoxianfeng@iie.ac.cn
ARSA can still guarantee a high PSNR in the case of high
packet loss rate.
Keywords Error resilient coding · H.264/AVC · Robust
FMO · Adaptive redundant slice allocation
1 Introduction
With the widely use of smart phones, tablet computers and
many other mobile terminals, there has been an increas-
ing demand for transmitting compressed video streams over
wireless channel, such as video telephony, video on demand
service and so on. However, Visual quality of compressed
video may suffer great degradation when transmitted over
error-prone wireless channel, due to packet loss and bit error.
Figure 1 shows that there are serious regional blur and block-
ing artifacts in the frame when some packets are lost. So, it is
necessary to take some measures to prevent the degradation.
There are a lot of error-resilient tools for wireless video
transmission, such as data hiding [1–3], reference frame
selection (RFS), adaptive intra refreshment [4], forward error
correction (FEC) [ 5] and so on. H.264/AVC has introduced
some new error-resilient tools to enable reliable video com-
munication. Two of those tools are flexible macro-block
ordering (FMO) [6] and redundant slice (RS). FMO allows
encoder to define the coding order of MBs freely, and obtains
impressive performance of error resilience. RS places one or
more coded representations of a MB or slice into the bit
stream to protect the particular MB or slice.
There are 7 FMO Types in H.264/AVC, which define dif-
ferent types of Macro-block Allocation map (MBAmap) and
different coding orders of MBs. FMO Type 0–Type 5 are
fixed patterns, for example, Type 0 distributes MBs to slice
groups in raster scan order within a picture and each slice
123