1. Multimedia Data Transmission over Wired/Wireless Networks
Bharat Bhargava
Gang Ding, Xiaoxin Wu, Mohamed Hefeeda, Halima Ghafoor
Purdue University
Website:
Phone:

2. Research Issues Multimedia transmission Networks
High data rate
Time sensitive
Networks
Variable or limited bandwidth
Time delay
Packet loss
Multimedia over wired/wireless networks
Error resilient data transport control
Seamless transmission over hybrid networks
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3. Multimedia Data Transport Control
Cross-layer rate control
Match multiple data streams to the available bandwidth
Cross-layer error control
Adaptively update upper layer error control parameters based on the current network condition
Data Link Layer
Error detection
Retransmission
Application Layer
Data compression
Cross-layer
Control
Module
Physical Layer S1 S2 S3 S4 S5 S6 S7
Raw data
Transport Layer B1 B2 B4 B3 R1
Data Link Layer
Error detection
Retransmission
Application Layer
Data decompression
Physical Layer R4 R3 R2 R7 R6 R5
Cross-layer
Control
Module
Transport Layer
Raw data
B: rate control, S: sender’s rate control, R: receiver’s rate control
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4. Multimedia Data Transport Control
Movie
Original
Peak Signal
Noise Ratio
(dB)
Regular approach:
Link layer
rate control
Our approach:
Cross-layer rate control
Cross-layer rate + error control
Sent enhancement
layer (%)
Sent PSNR
Sent PSNR
Received PSNR
Parity data R
(Byte)
Star Wars IV
37.225
80.055
35.711
98.222
37.088
14.598
Citizen kane
37.791
88.333
36.825
97.556
37.564
Aladdin
36.107
28.944
29.761
38.221
30.385
Jurassic Park I
36.661
64.444
33.941
88.444
35.649
Silence of Lambs
37.975
30.665
33.697
40.887
34.058
Star Wars V
36.595
62.611
34.386
89.000
35.841
The Firm
36.782
76.611
35.065
94.889
36.340
Terminator I
37.199
69.889
34.287
36.618
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5. Multimedia Data Transport Control
G. Ding, B. Bhargava and X. Wu, and “Cross-Layer Algorithms for Video Transmission over Wireless Networks,” In Handbook of Algorithms for Mobile and Wireless Networking and Computing, CRC Press, 2005.
Video transmission over wireless networks is challenging due to the time-varying bandwidth and the error-prone wireless channel. This paper reviews the state-of-the-art research on video compression algorithms and network protocols to improve quality of service. The cross-layer network control algorithms are proposed, in which the lower layers of wireless networks cooperate with the application layer to adjust error control strategy and transmission rate. The theoretical analysis and simulation results show that, with the inter-layer communication, the proposed algorithms can significantly improve the efficiency of error control and the accuracy of transmission rate selection. The implementation issues of applying the proposed algorithms to 3G mobile networks and IEEE wireless local area networks are discussed.
G. Ding, H. Ghafoor and B. Bhargava, “Resilient Video Transmission over Wireless Networks,” In IEEE International Conf. on Object-oriented Real-time Distributed Computing, Japan, May 2003.
Proposes an error resilient video transmission architecture over mobile wireless networks. Radio link layer, transport layer, and application layer are combined to deal with high error rate in wireless environments. The algorithms for both sender and receiver are given. An adaptive algorithm is further presented to automatically adjust parity data length in error control. The performance of the proposed algorithm is analyzed by both theory and experimental results.
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6. Multimedia Data Transport Control
References
B. Bhargava, S. Wang, M. Khan and A. Habib, “Multimedia Data Transmission and Control using Active Networks,” Journal of Computer Communications, 2005
B. Bhargava, C. Shi and Y. Wang, “MEPG Video Encryption Algorithms,” Journal of Multimedia Tools and Applications, 24, 57-79, 2004.
G. Ding, B. Bhargava and X. Wu, and “Cross-Layer Algorithms for Video Transmission over Wireless Networks,” In Handbook of Algorithms for Mobile and Wireless Networking and Computing, CRC Press, 2005.
G. Ding, H. Ghafoor and B. Bhargava, “Resilient Video Transmission over Wireless Networks,” In IEEE International Conf. on Object-oriented Real-time Distributed Computing, Japan, May 2003.
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7. Multimedia Transmission over Hybrid Networks (Planed Research)
To transport multimedia data over both back-bone and wireless networks, an intermediate Proxy or agent can be used
Located at the junction of backbone wired network and wireless networks
Performs media format transformation
Dynamically collects network condition from various wireless links
Makes adaptive QoS control, scheduling, and caching of multimedia data transmitted at different rates
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8. Adaptable Video Conferencing
Video conferencing systems (VCS) have become practical in commercial and research institutions because the advances of technologies in networking and multimedia applications. A video conferencing session involves multiple parties, possibly geographically interspersed, which exchange real-time video data. However, anomalies such as site failure and network partitioning affect the effectiveness and utilization of the communication capabilities. Video conferencing systems lack the ability of dynamically adapting themselves to the variations in the system resources such as network bandwidths, CPU utilization, memory and disk storage. In VCS, changes in parameters such as frame sizes, codec schemes, color depths, and frame resolutions can only be made by users. They cannot be made based on the system measurements of currently available resources. We need to limit the users' burden in keeping the system running in the most suitable mode to current environment and make it possible to provide the best possible service based on the status of the system. Incorporating adaptability into a video conferencing systems minimizes the effects of the variations in system environments on the quality of video conference sessions.
In the report, we discuss the concept of adaptability and the basic idea for achieving adaptability in a video conferencing system, give a description of common anomalies encountered in a distributed system, review the NV video conferencing system, the testbed of our experiments, describe the extension and modification to NV and discuss some reconfiguration issues. A summary of experimental data analyses and observations are presented.
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9. Adaptable Video Conferencing
A video conferencing system should provided some policies and mechanisms to make it adaptable to the anomalies based on the available resources. The advantages of the adaptability schemes for VC system include:
Heterogeneity: A VC system will adapt to heterogeneous environments. That is, a video conference session can be held on different hardware platforms and different networks.
Scalability: A VC system will adapt itself as more users, more sites join a video conference in progress.
Anomaly Management: A VC system will adapt to anomalies and degrade gracefully when available resources decrease or become unavailable.
Resource Management: A VC system can make efficient use of resources like storage, CPU time, and communication bandwidth.
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10. Adaptable Video Conferencing
Timeliness/Accuracy/Precision (TAP) cannot be maintained at the highest level simultaneously during anomalies. We must trade
among these attribute values. The policy to trade among these attributes can be described as follows:
Maintaining Timeliness when Bandwidth Decreases
Reduce frame size (The accuracy is maintained unless the frame size is below a certain value).
Reduce frame resolution (Both accuracy and precision are reduced).
Dither color frame to black and white.
Compress color depth.
Switch to a codec scheme that has a higher compression ratio (Side effect: CPU utilization increases. This can be compensated by frame resizing and resolution reduction).
Maintaining Accuracy when Bandwidth Decreases
Switch to a lossless codec scheme with reduced frame size.
Compress color depth (compress Y and UV no more than 2 bits each).
Do not use lossy codec schemes.
Do not reduce frame size or resolution by a big factor.
Maintaining Timeliness when CPU Utilization Increases
Switch to a codec scheme that requires less computation (usually with lower compression ratio).
Reduce frame size.
Do not compress color depth.
Do not reduce frame resolution.
Maintaining Accuracy when CPU Utilization Increases
Switch to a lossless codec scheme
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11. Adaptable Video Conferencing
References
B. Bhargava, “Adaptable Video Conferencing”.
B. Bhargava and S. Li, “Exploring Adaptability for Video Conferencing”.
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12. Peer-to-peer Multimedia Streaming
PROMISE: PeertoPeer Media Streaming Using CollectCast
Peer lookup
Peer-based aggregated streaming
Dynamic adaptation to network conditions
PROMISE is based on a new application level peer-to-peer service: CollectCast
Inferring and leveraging the underlying network topology and performance
Monitoring the status of peers and connections and reacting to peer/connection failure or degradation with low overhead
Dynamically switching active senders and standby senders so that the collective network performance out of the active senders remains satisfactory
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13. Peer-to-peer Multimedia Streaming
CollectCast is installed on peers between the p2p substrate and the applications.
PROMISE is a sample application. Other applications may include scientific data streaming.
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14. Peer-to-peer Multimedia Streaming
References
A. Habib, S. Fahmy and B. Bhargava, “On Monitoring and Controlling QoS Network Domains,” International Journal of Network Management, 2005.
M. Hefeeda, B. Bhargava and D. Yau, “A Hybrid Architecture for Cost-Effective On-Demand Media Streaming,” Journal of Computer Networks, 44(3): , 2004.
M. Hefeeda,  A. Habib, B. Botev, D. Xu,  and B. Bhargava,  “PROMISE:  Peer-to-Peer Media Streaming  Using CollectCast,”  In Proc. of  ACM Multimedia 2003, pages 45-54, Berkeley, CA,  November 2003.
M. Hefeeda and B. Bhargava, “On-Demand Media Streaming Over the Internet,” In Proc. of  9th IEEE  Workshop on  Future Trends of Distributed Computing Systems (FTDCS),  pages , San Juan, Puerto Rico, May,  2003.
D. Xu, M. Hefeeda, S. Hambrush, B. Bhargava, “On Peer-to-Peer Media Streaming,”  In Proc. of  IEEE  International Conference on Distributed Computing Systems (ICDCS), pages , Vienna, Austria, July 2002.
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15. More Issues Multicast and broadcast of multimedia data
Multimedia communication over next generation wireless networks
Wireless local area network
IEEE n of 100 Mbps
Wireless personal area network
IEEE a of 55 Mbps or higher
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