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Scalable Video with Unequal Error Protection over 802.11b/g Host Publication: Finds and Results from the Swedish Cyprus Expedition: A Gender Perspective at the Medelhavsmuseet Authors: R. D'haenens, J. Doggen, D. Bakker and T. Dams Publication Year: 2008
Abstract: We developed a simulation set-up that can test the
behaviour of streaming applications over an error-prone wireless
networks: 802.11b/g specifically. The application we tested is a
video coder that adds unequal error protection to the scalable
extension of H.264/SVC. This protection mechanism enables the
recovery of lost packets. We adapted a radio wave propagation
model to define Rayleigh fading which is able to model packet
reception correctly for indoor environments. We investigated
how the video encoder creates RTP packets and we noticed a
very small payload, resulting in a high protocol overhead of
54%. We recommended the encoded designers to use UDP lite
because it does not discard corrupt packets, as UDP does, but
allows them to pass to the video decoder. This ensures more
incoming information that can be evaluated at the application
layer. The simulation of the 802.11b/g networks with bad wireless
network conditions proves the correcting capabilities of the video
decoder. The decoder could repair lost packets, or ensure graceful
degradation. However this graceful degradation could not be
maintained when the packet losses become too high, as for
example when moving out of reach of an access point.
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