protocols for video conferencing and surveillance you are here brian schott ladan gharai colin...
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Protocols for Video Conferencing and Surveillance
You Are Here
Brian SchottLadan GharaiColin PerkinsCarl Worth
NETEX Industry DaySeptember, 2001
SITEX00: Twentynine Palms, August 2000
• DARPA SensIT exercise.• Prototype user platform was
laptop, HUD, GPS, compass.– Own location/bearing in
sensor network on topographical display.
– Eventual target is PDA.
• GUI communicated with Sensoria 1.0 nodes in field using instrumentation Ethernet backbone (wired).– Tracked GPS location
variation from survey.
– Exercised Sensorware-created maximal breach path algorithm as sensor nodes were moved.
You Are Here?
SITEX01: Twenty-nine Palms, March 2001
• In Sensor Field:– Wave Intensity Comparison –
multiple projections are made from seismic signal energy at sensor node clusters.
– Nine Rockwell HYDRA nodes.– Laptop with web cam.– COTS 802.11 wireless Ethernet
bridge to base camp (~1km).
• At Base Camp:– Situation status display GUI
(running on laptop).– Live video feed on wireless
PDA.
(ISI, VT, UCLA, Rockwell)
Device Min. (mW) Typ. (mW)Max. (mW) Notes
Processor + Memory 175 325 425
Running data acquisition and signal
processing
Radio (TX) 200 215 225 Transmitting at 10mW power level
Radio (RX) 170 190 200 In acquisition state, not locked
Radio (Idle) 25 40 50 Phase locked loop turned off
Sensors 123 145 160
Single channel data acquisition at max
sampling
Typical power numbers for RSC WINS Node
Hardware Baseline
• Rockwell WINS is a modular stackconsisting of:
Power Board StrongARM BoardRadio Board Sensor Board
• Fairly representative of other sensor nodes in the community.• We plan to adapt this node to allow module-level power
instrumentation and logging both in the lab and in the field.
Note: The processor has idle and sleep modes, but they are currently not implemented.
Robert ParkerUSC INFORMATION SCIENCES INSTITUTE
The Digital Amphitheatre - Scaling Multimedia Conferencing
For more information visit: http://www.east.isi.edu/projects/NMAA/.This work is supported by the DARPA under the Next Generation Internet program.
After capturing an image of the background, the subject enters the picture.
The difference between the original background and the current image is
calculated, and used as a mask. Pixels in the image are replaced by those of a
replacement background, based on the mask. The algorithm runs in real-time on a
standard workstation.
The Digital Amphitheatre is a collaborative environment for large scale multimedia
conferences and meetings.
The innovative use of standard protocols, combined with distributed computation and
digital signal processing, results in a conferencing environment which scales to
hundreds of participants.
.
Next GenerationInternet
STA
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Background Substitution Spatial TilingEach user sends video to a spatial
tiling agent (STA). The STA then “tiles” groups of up to 15 video streams into an single video stream. This results in fewer packets and
therefore less packet overhead and processing time. Graph (a) displays the reduction in packets per second (pps) for the H.261 video streams in the highlighted block, graph (b) shows that the
bit rate/quality is unchanged.
(a) (b)
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Dat
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Time(seconds)
'tiled-h261-bps''separate-h261-bps'
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Time(seconds)
'tiled-h261-pps''separate-h261-pps'