jung-hwan [email protected] low redundancy layered multiple description scalable coding using the...
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Jung-Hwan [email protected]
Low Redundancy Layered Multiple DescriptionScalable Coding Using The Subband Extension OfH.264/AVC
Department of Electrical and Computer EngineeringThe University of British Columbia
Written by Hassan Mansour, Panos Nasiopoulos, Victor Leung
07.04.25 Operating System Lab
Outline
Abstract Introduction Subband Extention Of H.264/AVC Multiple Description Scalable Coding Proposed Layered Multiple Description
Scalable Coding Experimental Results Conclusion
Abstract
The task of broadcasting video in wireless environments Requires coding efficiency and error resilience techniques.
and bandwidth utilization The one hand, error resilience and recovery from packet
delay or loss.
Layered Multiple Description Scalable Coding (LMDSC) Video broadcast over wireless networks Subband extension of H.264
Multiple Description Coding (MDC) Eliminating redundancy between the video streams
Introduction
Video transmission over wireless networks Problem
The highly error-prone nature of wireless environments The unexpected variations in available bandwidth
Solution The demand for bandwidth adaptive codec. Robust error resilience techniques.
Multiple Description Coding (MDC) Path or server diversity can reduce the effects of packet delay
and loss It suffers from data redundancy and thus requires additional
bandwidth.
Subband Extention Of H.264/AVC
Frames A and B from the original video sequence, a High Pass (HP) frame is produced after the prediction step and a Low Pass (LP) frame is produced after the update step.
Each set has half the temporal resolution as that of the original stream.
Subband Extention Of H.264/AVC
The packets contain HP information, then the decoder can be modified to recover from packet loss by inserting a zero residual frame instead of the lost frame.
A LP packet is dropped, then the consequence is more severe since that can greatly affect the PSNR and quality of the decoded stream.
Multiple Description Scalable Coding
Multiple Description Coding (MDC) First Launched Error resilience technique for the
reliable transmission of video over the wireless networks.
Complementary video streams are transmitted from one or several server locations along different paths to the client.
Second step in the evolution of this technology by merging scalable coding
Scalable coding facilitated the adaptability of the different video descriptions to variations in channel bandwidth
Proposed Layered Multiple Description Scalable Coding
Channel-bandwidth adaptive since the HP packets have a priority measure.
LP and lower layer packets have a higher priority than higher layer packets such that in the case of network congestion or a sudden reduction in channel bandwidth, higher layer (lower priority) HP packets are dropped to ensure the correct reception of higher priority packets.
Experimental Results
Conclusion
Layered Multiple Description Scalable Coding (LMDSC) Offer clients with non-homogeneous bandwidth capabilities,
video data that can adapt to channel bandwidth fluctuations and error recovery at very low bit-rates.
LMDSC significantly surpasses the decoded When faced with the same number packet losses.
LMDSC to support variable channel bandwidth error resilience non-homogeneous bandwidth capabilities