From owner-freebsd-multimedia Wed Jul 21 0:34:53 1999 Delivered-To: freebsd-multimedia@freebsd.org Received: from labinfo.iet.unipi.it (labinfo.iet.unipi.it [131.114.9.5]) by hub.freebsd.org (Postfix) with SMTP id 1ED1E15471 for ; Wed, 21 Jul 1999 00:34:37 -0700 (PDT) (envelope-from luigi@labinfo.iet.unipi.it) Received: from localhost (luigi@localhost) by labinfo.iet.unipi.it (8.6.5/8.6.5) id HAA23720; Wed, 21 Jul 1999 07:07:31 +0200 From: Luigi Rizzo Message-Id: <199907210507.HAA23720@labinfo.iet.unipi.it> Subject: Re: newpcm writeup To: utz@serv.net (The Utz Family) Date: Wed, 21 Jul 1999 07:07:30 +0200 (MET DST) Cc: jkh@zippy.cdrom.com, gandalf@vilnya.demon.co.uk, multimedia@FreeBSD.ORG In-Reply-To: from "The Utz Family" at Jul 20, 99 11:35:12 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 1923 Sender: owner-freebsd-multimedia@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > On a slightly more concrete note, tell us about feeder.c. Is this the code > that you base your assertion that you can do on the fly translation > successfully? ( i noted the mention of multiple formats in the code ) > > If i assume that this is indeed the case, then why would you do it in sw? > Dont most of the MSS or SB based cards have registers that you set to > inform the card that it's getting/(or expected to output) a given format? some such cards do not support all formats one would desire, or they do in the data sheets but the chip is broken. the conversion is present also in voxware and pcm just for the reason above. a nicer feature would be to do conversion of *sampling rate*, and here i agree with you that the card should do this if possible, not the CPU. unfortunately MSS and SB cant' do that... cheers luigi > My limited experience with sound and video processing would lead me to > conclude that one would rather have the *card* burn cycles on formats > instead of the *cpu*, because the card will just have to wait on the > cpu otherwise. > > of course, if you have multiple PIII's and gigs of ram then this sort of > processing would be effectively instantaneous wrt the human ear :-) > > Please excuse my ignorance if i am completely off base! > > On Tue, 20 Jul 1999, Jordan K. Hubbard wrote: > > > An even more interesting design... When can we see it? :) > > > > - Jordan > > > > > > > > > > for the interested, a brief writeup on newpcm is now available at > > > > http://www.vilnya.demon.co.uk/design.txt > > > > > > great graphics btw ! > > > > > > cheers > > > luigi > > > > > > > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > > with "unsubscribe freebsd-multimedia" in the body of the message > > > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-multimedia" in the body of the message > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-multimedia" in the body of the message