If these drivers do patch the kernel...can I have something that doesn't?

The Logitech, Inc. QuickCam Pro 4000 works fine.

-- "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety'' Benjamin Franklin 1775

On 3/30/06, Lamar Owen lowen@pari.edu wrote:

On Thursday 30 March 2006 06:20, Ryan wrote:

...

I recommend Axis webcams.

While pricey, many of their models are client OS-independent, and they run a form of Linux as their OS.

A less expensive alternative to the Axis is the VCenter or Gadspot camera line. www.gadspot.co.uk I think is the webpage.

All these cams are 100$ plus whereas webcams for windoze are available for 10-20$.

Whats the difference....something must b different in hw. Why should one buy these rather than the cheap ones? any performance/bandwidth optimization gains or maybe picture clarity?

With regards. Sanjay.

On Thursday 30 March 2006 19:43, Sanjay Arora wrote:

All these cams are 100$ plus whereas webcams for windoze are available for 10-20$.

Even the $10 cams work fair under Linux. However, most USB cams use isochronous transfers (which eliminates SRAM framebuffering and glue logic on the cam, which is why they are so cheap); more than one device on the USB cannot go isochronous at one time (in practice this is true, although there are no software safeguards to prevent it). You might get away with two USB isochronous cameras at once, but three is really asking for it (been there, done that. Ruined a complete project because of it; needed four cameras plus a USB control interface on a single PC, and would not work, on Windows or Linux; saved a few dollars on the cams and wasted hundreds on getting it to work. The PC was a full-bore Dell PowerEdge Xeon server with three UCB 2.0 controllers; it simply did not matter, as when two isochronous devices needed servicing at the same time things broke, all the way up to hard kernel hangs. Now, these were in the days of Fedora Core 2, and prior to the release of CentOS 4, so perhaps things have changed; funding for that project has ended, and the project terminated.).

The network cameras present virtually zero load to the hosting PC.

Whats the difference....something must b different in hw. Why should one buy these rather than the cheap ones? any performance/bandwidth optimization gains or maybe picture clarity?

The VCenter and Gadspot cameras are Ethernet cameras and full fledged microservers in their own right, and are a joy to use. You use curl or similar to grab images, or gateway directly to the camera for streaming jpeg. No PC required for the streaming side; $100 each is cheap compared to a PC.

The cheaper the camera, the more is offloaded to the PC; and even the fastest PC made cannot do multiple isochronous devices without issue.