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To: Michael Smith <msmith@atrad.adelaide.edu.au>
cc: terry@lambert.org, freebsd-hackers@freebsd.org
Subject: Re: video capture driver interface to file system? 
In-reply-to: Your message of "Fri, 18 Apr 1997 12:25:42 +0930."
             <199704180255.MAA21055@genesis.atrad.adelaide.edu.au> 
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Date: Thu, 17 Apr 1997 20:04:28 -0700
From: Amancio Hasty <hasty@rah.star-gate.com>
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Hi,

Not interested in using write nor any user level api.

the video capture driver can place a digital image any where in memory or
on video cards (PCI to PCI transfer).

For the purpose of this discussion, what I want to do is when I get a frame
in a buffer to pass a token to a file system routine to write the buffer
to disk.  The object is to avoid unnecessarily copying the buffer.

	Tnks,
	Amancio

>From The Desk Of Michael Smith :
> Amancio Hasty stands accused of saying:
> > 
> > If you guys are still interested in technical stuff. We need a very
> > fast mechanism to store images to disk. Suggestions?
> 
> From where?  ie. where is the source of the data?  A device driver, or
> an application?
> 
> > fxtv is a nice multimedia app which basically turns your PC to a TV.
> 
> If you want to use files in a filesystem, write() is pretty good 8) If
> that's too slow, try using a disk partition (ie. write a userspace
> filesystem with just the primitives you need).  Make sure you
> experiment with both the raw and cooked disk interfaces to see which
> works best for you.
> 
> > 	Amancio
> 
> -- 
> ]] Mike Smith, Software Engineer        msmith@gsoft.com.au             [[
> ]] Genesis Software                     genesis@gsoft.com.au            [[
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