From owner-freebsd-multimedia Sun Mar 1 21:49:22 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id VAA14831 for freebsd-multimedia-outgoing; Sun, 1 Mar 1998 21:49:22 -0800 (PST) (envelope-from owner-freebsd-multimedia@FreeBSD.ORG) Received: from labinfo.iet.unipi.it (labinfo.iet.unipi.it [131.114.9.5]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id VAA14824 for ; Sun, 1 Mar 1998 21:49:17 -0800 (PST) (envelope-from luigi@labinfo.iet.unipi.it) Received: from localhost (luigi@localhost) by labinfo.iet.unipi.it (8.6.5/8.6.5) id FAA19981; Mon, 2 Mar 1998 05:17:20 +0100 From: Luigi Rizzo Message-Id: <199803020417.FAA19981@labinfo.iet.unipi.it> Subject: Re: Creating MP3's under FreeBSD... To: taob@nbc.netcom.ca (Brian Tao) Date: Mon, 2 Mar 1998 05:17:19 +0100 (MET) Cc: freebsd-multimedia@FreeBSD.ORG In-Reply-To: from "Brian Tao" at Mar 1, 98 11:12:02 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Sender: owner-freebsd-multimedia@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > > using them, you still need to patch tosha, or better cdda, to grab > > the pcm files and compensate the sync problems which many drives > > have (don't ask for more comments on this, i am not very clear on > > what is the problem and how to fix it) > > Hrm... is this why I consistently hear "hiccups" in certain probably yes, but i am no expert on this, i just repeat what i have read. > tracks? cdd says it has jitter control, but it doesn't seem to help. > The problem spots always occur at the exact same spot in a track, and > appears to be tied to particular models of drives. Skips heard from a this seems to be also my experience, i.e. multiple reads from a drive return the same data (including skips). i did not have the time to investigate the problem in more detail, so i have no idea on a possible fix. The ioctl for reading from ATAPI CDROM seems to return an error every now and then, presumably in presence of the hiccups. I have no idea if the problem is repeated or skipped blocks (the former would be easier to fix) and whether or not there is a deterministic procedure to recover, like say restart reading on 1-sec boundary, or whatever (it would be very strange not to have a deterministic recovery procedure). I have to say that this "sync" problem looks very odd, and i don't know if it is there voluntarily (e.g. to obstacle piracy) or it is just the result of some bug in the design of the audio CD format! cheers luigi -----------------------------+-------------------------------------- Luigi Rizzo | Dip. di Ingegneria dell'Informazione email: luigi@iet.unipi.it | Universita' di Pisa tel: +39-50-568533 | via Diotisalvi 2, 56126 PISA (Italy) fax: +39-50-568522 | http://www.iet.unipi.it/~luigi/ _____________________________|______________________________________ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-multimedia" in the body of the message