Improving Web Cam Performance

[crokett]

My inlaws have an older laptop - PIII class processor w/512 MB RAM. They have a webcam and the video is herky-jerky. The laptop has USB 1.1 onboard, I tried a USB 2.0 PC card in it that locked up the 3 laptops I installed it in. I tried another that causes the machine to reboot whenever a device is attached. (older driver for it and there are no updates) The webcam works fine on my wife's laptop (faster processor and USB2.0 but same RAM)

At this point, will more RAM help or should I try another USB 2.0 adapter? Or is the processor just too wussy?

And I appreciate the irony - every day I fix several million dollars worth of computer equipment but can't get a simple webcam working.

[Kristofor]

When you're seeing the slow performance what is the memory and CPU utilization like on the laptop? If all of the physical RAM is being used and 3% CPU that would point one way, etc...

Of course watching for a sale you could buy a laptop with a CoreDuo, 1-2GB of RAM, and a faster HDD for under $400... Be careful not to spend too much time or money upgrading an old PC.

Kristofor.

[maxparot]

Most web cams will not start to exhibit decent frame rates until the subject and room are very well lit. Try adding in a pair of lights to get the lumens up and the shadows limited. With enough light I was able to pump 24-30 frames/second over a cable connection using a PIII-900mhz with 512 MB RAM using windows 98 second edition. A USB 1.0 or 1.1 interface is fine for this if it is the only USB device on the port.

[crokett]

Kris,

That is a brilliant idea to use perfmon and illustrates my point exactly. 10 years ago that would have been the first thing I'dve done. Now it never even occurred to me. But, if you are backing up 100 gig of data a night from West Boonieville to Timbucktu and something goes sproing, I'm your guy.

Max, I will try a different camera. I have a spare somewhere. My in-laws have a fancy Creative Labs one. with face recognition and all this other stuff. Mebbe the SW is getting in the way. My wife has an older Intel that works fine. When everybody is in the same room, same lights, etc the Intel works, the CL is jumpy video, blurry picture, etc.

[poolhound]

I would try and see if you can find a USB2.0 adaptor that works. The difference in bandwidth is huge. USB1.1 was about 12Mbps while USB 2.0 or HiSpeed USB is 480Mbps. This will help with getting the video from the cam to the PC as efficientley as possible.

Can you speak more about the actual symptoms. You say the video is "Herky jerky." is this when just looking at yourself in test mode or in a live video call. Is the video from the other end also "herky jerky?"

If its during live calls then you make no mention of the bandwidth of the internet connection. If this is not fast enough even the fastest PC will have challenges. what are they using and what upload download speeds are they actually getting. there are various places on the net you can run a test on the connection, I quite like this one.

http://www.speakeasy.net/speedtest/

[crokett]

The herky jerky is on the local PC. The way I have been testing is to attach the camera, start NetMeeting and tell netmeeting to get the video. It is out of focus, there is a severe lag and there are lots of frames getting dropped. At best you can tell you are looking at a face but it is not recognizeable.

The internet speed appears to be ok. We tested one-way with my wife's camera and they say they can see it with no issues.

[poolhound]

does the webcam have its own utility that can test the cam to computer connection? Whats the resolution of the cam?

I may have got the math wrong but at 640x480 x 16bits thats nearly 5Mbits per frame. If the frame rate were 30fps then you would need 150Mbps for just the data not counting the protocol overhead. Try an alternative USB 2.0 card and see what happens.

You could also try (as a test) to lower the frame rate and resolution an see if you can see any improvement.