The Access Grid at Vislab Chris Willing chris@vislab. usyd. edu. au Vislab University 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 Command Center - reference site Tiled rear projection array of 6 Model 200 ILA Projectors
Smart. Spaces, Stanford Courtesy of Pat Hanrahan, CS - Stanford
Power. Wall, Princeton Courtesy of Kai Li, CS - Princeton 8 x commodity projectors
High Density Tiled Display, SDSC http: //vis. sdsc. edu/research/tileddisplay. html 3 x 3 array with common light source
(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, Vis. Lab 2001 3 x 1 array, 3840 x 1024 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
Normal screen 1280 x 1024 Widescreen 5120 x 1024
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? Multicast 3 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 cameras projectors (monitor) video audio mics Gentner PA
Access Grid Sydney Preparing for SC-Global: test “cruises” + A/G-Sydney
ATP display Projected display 3840 x 1024 Mon. display network
ATP video capture screen camera table video projectors network mon.
ATP audio capture 1 x Radio mic Rx 2 x PZM Gentner PA audio mon. network
Gentner – echo control Site A Site B echo delay due to - distance - application buffering
Vislab Implementation (Physics) Projected display 2560 x 1024 2 x cameras 1 x video Polycom Soundstation network Mon.
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)
Differences to ANL • Linux only – stability – sync with vvd (not CORBA event handler) – potential for compute clustering (open. Mosix) • Graphics cards (n. Vidia Quadro 4) – use “well known” visualisation apps e. g. performer, open. Inventor, open. DX – potential for video clustering (chromium)
Video clustered AG projectors monitor cameras 1 display 2 video 3 audio mics Gentner PA
Performer with AG
High Resolution with AG
Future • Video clustering, stereo viewing • Shared event stream • Higher resolution (PAL, HDTV) – H 263, hardware MJPEG • External machine capture • Coexistence with H 323 (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
Скачать презентацию The Access Grid at Vislab Chris Willing chris vislab
ea7458f88f93b9127946a4794fdb970b.ppt