The Access Grid at Vislab

Chris Willingchris@vislab.usyd.edu.au

VislabUniversity of Sydney, Australia.

Today

• Background

• Differences to “traditional” vc

• Vislab Implementation – ATP

• Vislab Implementation – Physics

• Virtual Venues

• Differences to ANL implementation

• Future Work

Background

• VISLAB – visualisation, high perf. Computing

• Labs at Physics, ATP

• Bernard Pailthorpe at SDSC in 2000– High resolution displays– AG node

• Start April 2001 for SCGlobal, November 2001

Hyogo Prefecture (Japan) Police Hyogo Prefecture (Japan) Police Command Center - reference siteCommand Center - reference site

Tiled rear projection array of 6 Model 200 ILA Projectors

SmartSpaces, Stanford

Courtesy of Pat Hanrahan, CS - Stanford

PowerWall, Princeton

Courtesy of Kai Li, CS - Princeton

8x commodity projectors

High Density Tiled Display, SDSC

3x3 array with common light source

http://vis.sdsc.edu/research/tileddisplay.html

(Background)

• VISLAB – visualisation, high perf. Computing

• Labs at Physics, ATP

• Bernard Pailthorpe at SDSC in 2000– High resolution displays– AG node

• Start April 2001 for SCGlobal, November 2001

Display, VisLab 2001

3x1 array,

3840x1024 pixels,

single light source

Application in archaeology: Angkor

(Today)

• Background

• Differences to “traditional” vc

• Vislab Implementation – ATP

• Vislab Implementation – Physics

• Virtual Venues

• Differences to ANL implementation

• Future Work

Differences – 1. traditional

• Each node sends image stream(s) to MCU which decides what is output to each node

• TV style

Differences – 2. access grid

• Each node sends image streams to a multicast group address

• Each node sees all other sources

but if

“Each node sees all other sources”

then

screen overload

e.g.

10 other sites, each with 3 cameras

=> 30 video streams

Normal screen

First Access Grid session at USyd on 29 Aug, 2001

Widescreen 5120x1024

Normal screen

1280x1024

Summary of Differences

• limited vs. rich user experience

• complex (studio) vs. simple (pc)

• proprietary vs. open

• expensive vs. cheap

• but richness requires pixels

Technology diversion 1

Unicast

3 streams to 7 sites = 21 video streams

Efficient but who pays?

Multicast3 streams to 7 sites = 3 streams (mostly)

Today

• Background

• Differences to “traditional” vc

• Vislab Implementation – ATP

• Vislab Implementation – Physics

• Virtual Venues

• Differences to ANL implementation

• Future Work

Vislab Implementation (ATP)

display

video

audio

Gentner

cameras

mics PA

projectors(monitor)

Access Grid Sydney

Preparing for SC-Global: test “cruises” + A/G-Sydney

ATP display

Mon.

display

network

Projected display 3840x1024

ATP video capture

video

network

table

screen

mon.

camera

projectors

ATP audio capture

Gentner

Rx

audio

network

1x Radio mic

2x PZM

mon.

PA

Gentner – echo control

Site A Site B

echo delay due to - distance

- application buffering

Vislab Implementation (Physics)

Mon.

network

Projected display 2560x1024

2x cameras

Polycom

Soundstation

1x video

Virtual Venues

• ANL runs Virtual Venues Server

• APAG server at http://venues.ap-accessgrid.org

• Virtual rooms characterised by facilities– Video multicast group address– Audio multicast group address– MUD location (back channel link for participants)

• Linux only– stability– sync with vvd (not CORBA event handler)– potential for compute clustering (openMosix)

• Graphics cards (nVidia Quadro4)– use “well known” visualisation apps

e.g. performer, openInventor, openDX– potential for video clustering (chromium)

Differences to ANL

Video clustered AG

display

video

audio

Gentner

cameras 1

mics PA

2

3

monitor projectors

Performer with AG

High Resolution with AG

Future

• Video clustering, stereo viewing

• Shared event stream

• Higher resolution (PAL, HDTV)– H263, hardware MJPEG

• External machine capture

• Coexistence with H323 (via VRVS)

Links

•http://www.vislab.usyd.edu.au/research/accessgrid/•http://www.vislab.usyd.edu.au/research/display/•http://www.accessgrid.org•http://www.scglobal.org•http://vis.sdsc.edu/research/tileddisplay.html