Re: OT: Why is usb data many times the cpu hog that firewire is?

[Oliver Neukum]

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.

	Regards
		Oliver
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