1. Tamer Shanableh
Title of thesis Heterogeneous Video Transcoding for Matching Network-Bandwidth
and End-System Constraints
Position: Student/Research Assistant
Degree awarded: PhD
Duration of study: October 1998 until October 2001.
Financial support EPSRC and partly funded by BTexact
Supervisor Prof. M. Ghanbari
Current affiliation
Department of Computer Science
School of Engineering
American University of Sharjah
Sharjah, UAE
http://www.geocities.com/tamershanableh/
Email: tshanableh@ausharjah.edu
Thesis abstract
In this thesis, ubiquitous delivery of pre-encoded video streams to a heterogeneous set of
end-systems via seamless network connectivity is addressed by means of heterogeneous
video transcoding and associated interframe error concealment. To this end,
heterogeneous video transcoding is defined as a process that dynamically adjusts the
characteristics or coding-parameters of pre-encoded video to match the underlying
network-bandwidth and/or end-system constraints. The proposed dynamic adjustments
include video format portability, video scalability support, bitrate and resolution
reductions. Thus, a pixel domain transcoder for converting the coding format of
MPEG-1,2 video into H.26x format with lower spatio-temporal resolutions is devised. It
is shown that spatial resolution reduction in the frequency-domain outperforms its pixel-
domain counterpart, which gives rise to a new pair of transcoding architectures:
frequency domain transcoding and hybrid frequency pixel-domain transcoding. Fast
methods for computing the motion compensation in the frequency domain are proposed
and tailored for each of the transcoding architectures. On the other hand, while the
above transcoders are aimed at unicast applications, heterogeneous transcoding is
extended to support multicast applications by means of deriving multilayer transcoders.
Thus, the SNR scalability of the MPEG-2 video standard is formalised. Based on which
two multilayer transcoders are derived, verified and evaluated. Consequently, the video
format portability transcoder is merged into the multilayer transcoder resulting in a more
generic form of heterogeneous transcoding that supports video scalability, format
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2. portability and bitrate/resolution adaptability. Additionally, the dynamic bitrate-
adaptability and video-layering of the multilayer transcoder is compared against the case
of employing pre-encoded multilayer video. Lastly, since in video-networking
applications loss or corruption of coded video can be unavoidable, the thesis builds upon
the motion compensation techniques proposed for the heterogeneous transcoder to
devise a novel interframe error concealment technique which is capable of concealing the
loss of large parts of corrupted coded-pictures.
Publications
Journal papers
J-1 Shanableh, T., & Ghanbari, M. (2003, September). Hybrid DCT/pixel
domain
architecture for heterogeneous video transcoding. Signal Processing:
Image Communication, 18(8), 601-620
J-2 Shanableh, T., & Ghanbari, M. (2003, June). Loss Concealment using
B-pictures Motion Information. IEEE Transactions on Multimedia. 5(2),
257- 266
J-3 Shanableh, T., & Ghanbari, M. (2001, March). The Importance of the Bi-
directionally Predicted Pictures in Video Streaming. IEEE Transactions
on Video Technology. 11(3), 402-414.
J-4 Shanableh, T., & Ghanbari, M. (2000, June). Heterogeneous Video
Transcoding Into Lower Spatio-Temporal Resolutions With Different
Encoding Formats. IEEE Transactions on Multimedia, 2(2), 101-111.
J-5 Shanableh, T., & Ghanbari M. (in press). Multilayer Transcoding with
format portability for multicasting of single-layered video. IEEE
Transactions on multimedia, To appear in 2005.
Patents
P-1 T. Shanableh, M. Ghanbari and M. Nilson “Multi-layer video transcoding,”
Patent no. GB0129609.4, December 2001
Conferences
C-1 Shanableh, T., & Ghanbari, M. (2001, October). Transcoding
Architectures for DCT-Domain Heterogeneous Video Transcoding.
IEEE Proc. of International Conference on Image Processing,
ICIP'2001. Greece.
C-2 Shanableh, T., & Ghanbari, M. (2000, September). Backward Tracking
of B-pictures Bidirectional Motion for Interframe Concealment of
Anchor Pictures. IEEE Proc. of International Conference on Image
Proc. ICIP'2000. Vancouver
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3. C-3 Shanableh, T., & Ghanbari, M. (2000, June). Heterogeneous Video
Transcoding to Lower spatial Resolutions and Different Formats. Proc.
of ICASSP'2000. Istanbul, Turkey.
C-4 Shanableh, T., & Ghanbari, M. (2000, May). Interframe Error
Concealment for Bursty Packet Losses in IP Environments Proc.
Packet video 2000. Italy.
C-5 Shanableh, T., & Ghanbari, M. (1999, April). Heterogeneous Video
Transcoding MPEG-1,2 to H.263. Proc. of Packet Video'99. New York.
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