I have a computer that's running VNC server. I would like to record a video of what's going on on this computer, if possible without installing additional software on that computer. Is there a program that can connect to the VNC server port and instead of displaying the screen save it to an (e.g. AVI) video file?

Background: One of our customers sometimes has problems with the software he bought from us when he's performing a complex procedure. To help him, we offered that someone (a service technician or programmer) watches what he's doing during that procedure to find out if he's doing something wrong or if there's a bug in the software.

Currently, this is done live via VNC. That has a few disadvantages:

• The service technician has to be in the office at the time. As the customers are in different time zones, that can be in the middle of the night.
• If the service technician forgets something or doesn't notice something, it's lost. There's no way to see what happened again.
• Only a single computer can be watched by one service technician at a time.

I know I could install normal screen-grab software on the computer, but we're talking about an embedded system with limited RAM, CPU, HDD space, so installing something new is not an easy decision. And VNC is already there.

I could of course open a VNC client on some office PC and capture that PC's screen, but I can only record one remote computer that way. I often have to watch up to 8 screens in parallel. (And I don't think that screen-grabbing VNC would improve image quality, either.)