Message-ID: <421D11A9.1090708@tmr.com>
Date: Wed, 23 Feb 2005 18:28:41 -0500
From: Bill Davidsen <davidsen@tmr.com>
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To: gene.heskett@verizon.net
CC: linux-kernel@vger.kernel.org
Subject: Re: OT: Why is usb data many times the cpu hog that firewire is?
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Gene Heskett wrote:
> 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.

You have gotten most of an answer, unless someone make a fireware to 
USB2 adaptor you are going to have to go slow or run firewire.

I would think the framerate could be quite slow and still be useful. 
What software do you use to do the detection (curiousity only)? Of 
course after you detect motion you probably want to up the framerate, so 
  you can see what's really happening.

-- 
    -bill davidsen (davidsen@tmr.com)
"The secret to procrastination is to put things off until the
  last possible moment - but no longer"  -me
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