Performance Issue in white board

[Binayak]

Hello Folks,
I find Big Blue Button white board almost unusable for my use
case.

UseCase: I teach algorithm online. Unlike a business
presentation, I scribble a lot on the whiteboard. Example:
http://www.youtube.com/watch?v=nNhpFO9CmPs

Issues: 1) There is a significant lag when I am writing
something. The red tip is very annoying.

Any help how to disable redtip from appearing and make the
scribbling without lag ( it should be as smooth as you drawing on
microsft paint).

Thanks

[Fred Dixon]

Hi Binayak,

> There is a significant lag when I am writing
> something.

There will always be lag, but to be a bit more precise, can you
quantify "significant". Is it on average 1 second, 3 second, 5
second, etc. Also, can you cross-check against

http://demo.bigbluebutton.org/

and let us know if you see any difference in lag.

We designed the whiteboad to actually be a series of points (not
bit-mapped overlay like MS Paint). We tried to make it fluid, but
you need to exact fluidity of a bitmapped environment, you can use the
desktop sharing to share a region of MS Paint (or any region on your
desktop), and draw within that region.

With desktop sharing, users will see pixel-to-pixel what you are
drawing. Try it and let us know the lag for updates relative to using
the built-in whiteboad.

Regards,... Fred

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[Binayak]

Hi Fred,
Thanks. It is difficult to quantify in terms of time. In stead I
have taken three screen capture to show how difficult it is to use BBB
whiteboard and scribble.

Case 1: Using Big Blue Button http://www.youtube.com/watch?v=DiZuSCM_1bY
( I have used the demo site)
Case 2: Using webex http://www.youtube.com/watch?v=-lyUaMk73mE
Case 3: Using MS Paint http://www.youtube.com/watch?v=Kfg4YZUIfSY

Web ex white board is almost same as native MS paint application. I
believe things will little bit improve if we can disable the red Dot.
Some time ago I have built a white board with Red 5 and I have seen
similar lags. However I had seen white board based on Flash Media
Server where I did not find any lag.

I did try a desktop sharing from USA to India. I was using skype
for audio. There are about 10 sec delay between voice and screen
refresh. I afraid that may not be a solution yet.

Thanks
Binayak

On Feb 21, 4:42 am, Fred Dixon <ffdi...@gmail.com> wrote:
> Hi Binayak,
>
> > There is a significant lag when I am writing
> > something.
>
> There will always be lag, but to be a bit more precise, can you
> quantify "significant".  Is it on average 1 second, 3 second, 5
> second, etc.   Also, can you cross-check against
>
>  http://demo.bigbluebutton.org/
>
> and let us know if you see any difference in lag.
>
> We designed the whiteboad to actually be a series of points (not
> bit-mapped overlay like MS Paint).   We tried to make it fluid, but
> you need to exact fluidity of a bitmapped environment, you can use the
> desktop sharing to share a region of MS Paint (or any region on your
> desktop), and draw within that region.
>
> With desktop sharing, users will see pixel-to-pixel what you are
> drawing.  Try it and let us know the lag for updates relative to using
> the built-in whiteboad.
>
> Regards,... Fred
>

[Binayak]

Any follow up answer. Here is another cool white board that looks
great too
http://www.imaginationcubed.com/

On Feb 21, 9:10 pm, Binayak <contact.ores...@gmail.com> wrote:
> Hi Fred,
>    Thanks. It is difficult to quantify in terms of time. In stead I
> have taken three screen capture to show how difficult it is to use BBB
> whiteboard and scribble.
>

>      Case 1: Using Big Blue Buttonhttp://www.youtube.com/watch?v=DiZuSCM_1bY

> ( I have used the demo site)
>      Case 2:  Using webex  http://www.youtube.com/watch?v=-lyUaMk73mE

>      Case 3: Using MS Painthttp://www.youtube.com/watch?v=Kfg4YZUIfSY

[Fred Dixon]

Hi Binayak,

We've opened an issue to track whether temporarily hiding the red dot
(such as when the presenter holds down the mouse button to draw) will
reduce network traffic and increase speed.

http://code.google.com/p/bigbluebutton/issues/detail?id=882

Denis Zgonjanin wrote the whiteboard, so you'll probably see him
respond to this thread.

I checked out imaginationcubed, and it's nice, but couldn't find any
link to the source (BigBlueButton is an open source project, so trying
to embed a closed-source component wouldn't be an option).

Regards,... Fred

[Binayak]

Thanks Fred. I have given example of imaginationcubed just for
comparison. I did also research some more and in the process of
developing a white board before I came to know about BBB. In my first
attempt I tried a simple white board based on Red5 and I am not at all
happy with the performance. I suspect Red5 is the cause of all
performance delay. Now I am trying on FMS and so I can compare between
two.

Thanks

On Feb 24, 5:01 am, Fred Dixon <ffdi...@gmail.com> wrote:
> Hi Binayak,
>

> We've opened an issue to track whether temporarily hiding the red dot
> (such as when the presenter holds down the mouse button to draw) will
> reduce network traffic and increase speed.
>
>    http://code.google.com/p/bigbluebutton/issues/detail?id=882
>
> Denis Zgonjanin wrote the whiteboard, so you'll probably see him
> respond to this thread.
>
> I checked out imaginationcubed, and it's nice, but couldn't find any
> link to the source (BigBlueButton is an open source project, so trying
> to embed a closed-source component wouldn't be an option).
>
> Regards,... Fred
>

[Denis Zgonjanin]

When you say lag, I'm assuming you mean the disappearance briefly of the last drawn whiteboard shape, before it re-appears again. 

The way the whiteboard currently works is it divides the whiteboard shapes into small manageable chunks as you're drawing a shape. The last drawn chunk is then sent to the server and the server broadcasts it to everyone in the room. As soon as the shape is sent to the server it is deleted on the presenter's view. It re-appears when the presenter gets the shape back from the server. This is done to ensure consistency of shapes across the clients, as in this case all clients have the same copy of each whiteboard shape.

To get rid of this 'flicker' effect, the whiteboard can be changed so that the presenter's local copy of the ast drawn shape is deleted not when the shape is sent to the server, but when the corresponding shape is received back. This will eliminate the flicker effect and any perceived lag.

Patches are welcome.

- Denis

[Oresoft Live Web Class]

Yes thats exactly what the problem is.

Thanks

[Denis Zgonjanin]

This issue has been fixed in master:

https://github.com/bigbluebutton/bigbluebutton/commit/e60bf5aa233dfb2746ee14cffb3c4cdd065c071e

- Denis