Video
networking is the generic name for video coding for transmission over packet
networks. Research in this field focuses on the two issues of Video
Compression/processing and Packet Networks.
On video compression (and processing)
we have done extensive investigations on various forms of compressing
(reducing) video bit rates, from very low bit rate video to super high
definition images, as well as processing video for various applications.
Published works in these areas are listed in the Publication
list. Of particular contributions are:
·
DCT based coding (H.261, MPEG 1&2, H.263
and H.264/AVC and SVC)
·
Wavelet
Transform/Subband coding
·
Vector and Lattice Quantzation
·
Fractal coding
·
Arithmetic coding
·
Motion estimation
·
Video segmentation and object tracking
·
Content based coding (MPEG 4)
·
Video data bases and retrieval (MPEG-7)
·
Video watermarking
On the Networking issues,
we have contributed mainly on the performance issues, especially when video
quality is assessed over packet networks, as shown in the Publication
list. The topics looked at include:
·
Flow and congestion control in Packet networks
·
Performance management/monitoring of packet
networks
·
Network and multimedia service pricing
·
Usage parameter control/admission control
·
VBR , UBR and ABR services
·
Protocol
for carrying multimedia services over LANs
·
Video over Internet
·
Video over wireless
·
Cross layer optimisation
·
Cell loss concealment of video
·
Video transcoding for
congestion control
·
Subjective assessment of video over packet
networks
·
Video Quality Meter
These activities are explained
in some details in Current Research Activity
and are summarized in a set of slides in
our Lab website http://www.essex.ac.uk/csee/research/vidnet_lab/index.aspx
(broadband access is required to download them!)