Cornell Box VTEL Video Conferencing options
Cornell University Program of Computer Graphics 		Cornell Seal

     

    Introduction

    The PCG video conferencing equipment is a VTEL Galaxy system with both a T1 and H.323 interfaces. The T1 is a fixed line that goes to UNC in NC. An optional dial-in interface may be added later. The VTEL PC is really a standalone device with little or no user intervention required for typical T1 based video conference. See the VTEL reboot document for details when the VTEL codec seems hung. Users needing the H.323 interface may need some extra help setting up a connection. Send mail to video@graphics.cornell.edu to make setup arrangements.

     

    VTC setup from 586 (library -- DEFAULT CONFIGURATION)

    Most video conferences are held in the library where the space is conducive for small meetings. The first setup item is to make sure that the video routing is correctly set. Routing can be changed either by logining in to harry.graphics.cornell.edu with telnet or by using the VT101 console in 551a. There is a video ID with password taped to the VT101. This login will automatically run the router software. Telnet users need to run /usr/local/bin/router.

    router> codec to yellow -- where yellow is the designation for the library.

    router> yellow to codec

    Turn on the library TV and use VIDEO-2 to setup the local camera (loop-back). The microphone should generally be placed on the table and be 12-24 inches from the speaker. View the codec input on VIDEO-3. Turn microphone 1 (symetrix amp under the TV) up to the black arrow. This makes the microphone hot and the system ready to go.

     

    VTC wrap-up from 586

    At the conclusion of a VTC in the library, turn microphone 1 (symetrix amp) down/off, turn off the TV, and return the microphone to the top of the TV.

     

    VTC setup from 551 (conference room) )

    The conference room is used for VTCs that have larger audiences such as remote lectures. There are many different configurations that make the system functional. The following configurations are typical.

    For a smaller local audience at the conference table

    router> codec to 12 -- where 12 is the monitor in the corner. It is also known as speakermon but routing 12 explicitly routes the audio & video.

    router> 12 to codec -- where 12 (source) is speakercam and the audio is micmix. Micmix is the Mackie 1202 mixer in 551a.

    For remote lectures with a larger local audience

    router> codec to proj2 -- VTEL codec NTSC video signal to the center projector.

    router> codec to amp -- VTEL codec audio signal to main speakers. Set amp to mono & turn off low level filter.

    router> codec to mixer -- VTEL codec audio signal to mixer. This will allow both the codec & local audio to be recorded on auxdecks.

    router> micmix to mixer -- local miccrophone signals to mixer.

    router> codec to auxdecks -- both ntsc video & audio get router to auxdecks. We're only interested in the video. For audio use the following.

    router> mixer to auxdecks -- this sends audio from both the VTEL codec and local microphones to auxdecks. This routing should be done after codec to auxdecks.

    router> speakercam to codec -- ntsc video for codec. If the lecture is originating here, then this signal will most likely get switched as appropriate.

    router> micmix to codec -- local microphone signal to the VTEL codec.

    router> speakercam to speakermon -- ntsc video to local monitor. This provides local feedback as to what signal we're sending out. The local camera monitor can be sent to any local monitor.

    Usage notes.

    Appropriate devices need to powered up.

    The lecture can be recorded on auxdecks with the previous routing layout.

    Microphone sources need to be turned on (wireless) and turned up to unity on the Mackie mixer. The exception will be if the knob on the mixer is marked otherwise.

    The Shure wireless microphone has a specific power-on sequence. The remote microphone needs to be powered on before powering on the base station. After both of these units are on, then the microphone can be turned on & off as needed. If the power from the wireless microphone is turned off while the rest of the system is on, then there will be lots of white noise that gets amplified.

    All of the microphones in the conference room go through the Mackie mixer. The output from the Mackie mixer is micmix.

     

    VTC wrap-up from 551

    At the conclusion of a VTC in the conference room, turn the different monitors, amp, VTRs, etc. off. Change the codec routing to codec to yellow & yellow to codec. This is the default routing for the VTEL codec.

     

    For problems or questions, send mail to video@graphics.cornell.edu

     

    The VTEL PC needs no adjustment for video conferencing
Last updated 05.11.00 PCG Home Page Search the PCG Site PCG Webmaster