An Error Resilient Video Coding
Algorithm Combining FEC and WZ
Technology over Error-prone Channel
Tianqing Wang
1
Zhengguang Xie
2
Hongkui Li
3
School of Electronics and Information
Nantong University, P. R. China
Abstract
Reliable video delivery has become one
of the crucial issues in wireless video
communications. Based on different error
resilient property of forward error
correction (FEC)and Wyner-Ziv (WZ),
we propose a scheme which combines
these two technologies. Experimental
results demonstrate the scheme can
possess their both advantages and have an
improvement in the average peak signal
to noise ratio(PSNR).
Keywords: Video compression coding
stream; Error resilient transmission; WZ
coding; FEC coding
1. Introduction
High compression video streams are very
susceptible to transmission errors over
error-prone channels. Almost all available
video codec such as H.264/AVC, MPEG,
follow the predictive coding paradigm
which causes the problem of error
propagation. In order to ensure the high
quality of the video signals’ transmission,
people use error resilient methods such as
redundant slices, flexible macro-block
ordering, and multiple description coding
[1] at the encoder. Moreover, at the
decoder side, technologies of
interpolation and estimation are used for
data recovery or error concealment [2].
However, these methods achieve poor
quality in the case of high packet loss.
Another method is using forward error
correction (FEC) [3].But if the error
probability overwhelms the estimated
probability of transmission errors, it
results in rapid degradation of the picture
quality, leading to the undesirable “cliff”
effect.
A new video coding technology --
distributed video coding (DVC)[4] has
become increasingly popular in recent
years. It is based on Slepian-Wolf’s and
Wyner-Ziv’s information-theoretic results
from the 1970s. In contrast to traditional
coding standards, DVC are encoded
independently but decoded jointly, which
shifts the computational complexity from
the encoder to decoder’s side. Since no
prediction loop exists at the encoder, the
compression stream has an intrinsic
robustness to error propagation.
Therefore, many error resilient schemes
[5-8] based on DVC have been proposed.
Among them, systematic lossy error
protection (SLEP) [6] turn out to be more
classical, it avoids cliff effect that FEC
brings at high packets loss but has poor
performance when the packets loss is low.
In the paper, we propose an error
resilient scheme combining FEC and WZ,
which possesses the benefits of the two
technologies. It has been proved that the
scheme has a better performance in terms
of visual quality.
2. Principles of FEC and WZ
Figure 1 shows the principle block
diagram of FEC. If noisy level is within
the correction capability of FEC, we can
International Conference on Information, Business and Education Technology (ICIBIT 2013)
© 2013. The authors - Published by Atlantis Press