Ripping wav files from iso image

[aluminumsulfate at earthlink.net]

   Cc: <gnhlug-discuss at mail.gnhlug.org>
   From: Bill McGonigle <bill at bfccomputing.com>
   Sender: gnhlug-discuss-admin at mail.gnhlug.org
   X-Original-Date: Mon, 25 Apr 2005 17:59:35 -0400
   Date: Mon, 25 Apr 2005 17:59:35 -0400

...

   I've heard people say that dd won't work because dd defaults to 2k 
   blocks and CD's have 2.3K audio blocks.  I can't see how that's 
   relevant if you're dumping to a flat file but I could be missing 
   something.

dd won't work because the IDE driver can't present the disk as a block
device. ccda and cd-rom (data cds) use different arrangements of
frames and subchannels to represent their data. While they both use
the same underlying frame format, their frames are tied together
differently.  The ide driver is only designed to interperet the data
in data tracks and present them to the kernel as block devices. To
read audio data, you need either a SCSI cd drive or ide-scsi emulation
turned on. Then, programs use SCSI commands to access
/dev/scsi/host0/bus0/target0/... or wherever your drive may be. And,
when they do that, they're totally bypassing the cdrom device driver.

   I guess part of the question is if dd just pulled bits off of the 
   disc/raw device that is /dev/cdrom or if the /dev/cdrom driver tried to 
   do something smart, like presenting a session as a device (in which 
   case it would probably ignore the CD Audio).

Well, if someone volunteered to write a cddafs, this might be
possible.  Until then, I'll just have to keep using cdda2wav -D 0,0,0
 -my-favorite-options.

Dave

P.S. *Grunt* If any of you upgrade to Emacs 21, make sure you (setq
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(i.e., you won't be able to post to gnhlug.org).