DELPHI and VRVS
The VRVS (Virtual Room Videoconferencing System)
is a set of programs for videoconferencing via internet. Delphi experiment starts
to use this system to broadcast meetings from CERN to other institutes. We have
obtained first experience during broadcasting Plenary Physics Meeting on 8th July 1999.
Here are some remarks:
- Sound quality
- The sound transmitted from the room 40/S2-A01 was good only when the speakers
used small microphone pinned on their jacket (T-shirt, blouse, ...), the bigger
microphones on the table were not sufficient. The switch on the microphone should be
in the position to give higher output (there are only two positions). The questions
from the audience were transmitted well, the portable microphone should be for every
comment and this microphone should again be switched to get higher output.
The sound from Council chamber was generally good, the reason is that it is much
bigger room and the speakers have to use microphone even for the audience present
in the room. We did not try to transmit questions from outside.
- Video quality
- The main reason for video transmission is to show transparencies. The
hand-written transparencies or transparencies printed with small fonts was
difficult (or impossible?) to read, the shape of histograms was clear (but
captions and axis descriptions were lost). The result would be better if we
would use document camera to scan transparencies, but this would deteriorate
the quality of the picture in the room. Given that the majority of the audience
was present in the room, we have chosen the first solution. The system enables
to transmit so called attached documents. The transparencies available as a PS
file could be sent by this way. So we encourage all speakers to use computer written
transparencies and to give them to us just before the meeting.
- Participants in the VC
- The number of participants outside the room was not too big - just one
for the morning session (thanks to Pierre for all comments regarding the sound
and video quality) and three for the afternoon session. But it was sufficient to
gain some experience and to demonstrate the possibilities of the VRVS. Just to
remind other interested users that you need only PC or workstation with sound
card and speakers or headphones to participate. All details about installation
can be found on the VRVS pages.
- Suggested improvements
- The VRVS system enables either public sessions or private sessions protected
by password. For the Delphi meetings, we use the protection. The system enables
to store the session on the hard disk, then it can be transferred via ftp and watched
from user machine. This enables good access for users with slower connection. But,
the current setup does not permit to use protection and storage on the disk
simultaneously :-( We have asked for changes.
Comments and questions send to email@example.com
Created by Jiri Chudoba.
Last modification: 9 July 1999