On Monday 21 February 2005 12:58, Oliver Neukum wrote: >Am Montag, 21. Februar 2005 18:16 schrieb Gene Heskett: >> Greetings; >> >> Motherboard is a biostar with nforce2 chipset, 2800xp cpu, gig of >> ram. >> >> I've recently made the observation that while I can view 30fps >> video from my firewire equipt movie camera with a minimal cpu hit >> of 2-3%, but viewing the video from a webcam on a usb 1.1 circuit >> takes 30-40% of the cpu, at half the frame rate. >> >> Do I have something fubar in the usb? Or is this just the nature >> of the beast? > >A video stream over usb1.1 must be compressed due to bandwidth > available. Decompression needs cpu. > Thats what I was afraid of, which makes using it for a motion detected burgular alarm source considerably less than practical since the machine must be able to do other things too. Darn. And its usb1.1 even when plugged into a 2.0 capable port.
One could probably use the FIR output of an EagleEye (X10 stuff) to start & stop a capture, but the lag inherent in that is less than 'optimum' IMO. Thank you Oliver. > Regards > Oliver -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) 99.34% setiathome rank, not too shabby for a WV hillbilly Yahoo.com attorneys please note, additions to this message by Gene Heskett are: Copyright 2005 by Maurice Eugene Heskett, all rights reserved. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
