Tele-conference demo

java-programmer, Tele-conference demo I know Microsoft has teleconference software, can
do tele-presentation, demo
But I prefer do things simple

I am thinking use java.awt.Robot class do
the screen catch every second, then write
to the image into a buffer file pipe
in web server.

Then in the web page create
an applet read from that buffer file pipe.

So when I doing demo, I start my program run
in background, do screen catch, write to web
server.

User just http to my applet page watch my demo.
This is similar to xwatchwin in X11 world.
But X11 world only work in intranet with small
group of people, require expensive X-terminal.
Today every PC has a browser, access to internet.

Do you think this is doable?
Any better idea?
Or such Java program already existed? (tell me the download link)
Thanks!

java-programmer >> Tele-conference demo RC wrote:
..
>But I prefer do things simple
>
>I am thinking use java.awt.Robot class do
>the screen catch every second, then write
>to the image into a buffer file pipe
>in web server.
>
>Then in the web page create
>an applet ...

An applet would need to be signed, and trusted,
before it could get screen captures.

Not exactly 'simple' for that aspect alone.
Normally I would advice anybody that is not
already very experienced with the J2SE
development, as well as GUI building, to
steer clear of applets.

If you can get the end user's trust, it
is probably easier to launch a free floating
application from the web page itself, using
web start.

HTH

--
Andrew Thompson
http://www.athompson.info/andrew/

Message posted via JavaKB.com
http://www.javakb.com/Uwe/Forums.aspx/java-gui/200704/1

java-programmer >> Tele-conference demo RC wrote:
> I know Microsoft has teleconference software, can
> do tele-presentation, demo
> But I prefer do things simple
>
> I am thinking use java.awt.Robot class do
> the screen catch every second, then write
> to the image into a buffer file pipe
> in web server.

How big a screen? 1024 x 768, maybe, at 24-bit color
depth? That's just under 19 Mbit/sec for each conference
participant, ignoring protocol overhead, retransmissions,
and so on. How fat is the pipe between the conference host
machine and the Internet? Or, how fast and how well can you
compress screen shots?

And is there an audio component? Do you plan to carry
it on the same channel, or in parallel over telephone lines?

> Then in the web page create
> an applet read from that buffer file pipe.
>
> So when I doing demo, I start my program run
> in background, do screen catch, write to web
> server.
>
> User just http to my applet page watch my demo.
> This is similar to xwatchwin in X11 world.
> But X11 world only work in intranet with small
> group of people, require expensive X-terminal.
> Today every PC has a browser, access to internet.

I'm not familiar with xwatchwin, but the fact that
it's limited to high-speed networks and small audiences
seems telling, does it not?

> Do you think this is doable?

Yes, but not economically. Not with today's technology,
anyhow. Wait ten or fifteen years, or do something smarter.

> Any better idea?

Serious teleconferencing software doesn't try anything
as basic as just transmitting screen images over and over
again. At the very least you'd make a streaming video of
it, and take advantage of frame-to-frame similarities to
get better compression. With more intelligence, you'd find
ways to transmit just the pieces of the screen that actually
changed, avoiding the (probably) large majority of pixels that
remain the same from one moment to the next.

--
Eric Sosman
email***@***.com