From: hugh (Hugh Daniel)
Date: Fri, 25 Feb 94 11:45:19 PST
To: cypherpunks
Subject: Droped messages...
Message-ID: <9402251945.AA03115@toad.com>
MIME-Version: 1.0
Content-Type: text/plain


  Last week toad.com had some problems with the cypherpunks mail list,
in cleaning up from all that (megs and megs worth of gunk) I found two
messages that I do not think got out to the list.
  Here they are (I could find no headders for them).
  Majordomo seems to be doing a great job, the load on toad.com is
down and messages are geting though much faster.  Ah, the power of
software!
		||ugh Daniel
		Your Sometimes Postmaster
		hugh@toad.com

-------- Mystery Message #1:

Phil Karn says...
> 
> >I have a program called direct to disk from OMI that lets me load
> >audio data from an Apple CD-SC300 or the Toshiba mech, outputting
> >AIFF, Sound Designer II and several other file formats.  The AIFF and
> >SDII formats are stereo 16-bit 44.1kHz; usually the QuickTime formats
> >are 8 bit.  So the AIFF and SDII formats have the full bit stream.
> 
> Not necessarily. It's possible that the data you see has been
> converted to analog and then back to digital. Many multimedia
> CD-ROM/sound card systems have this capability, but are not able to
> read the raw bits from a music CD.

No, the Sony and Toshiba drives have firmware that supports reading 
digital audio data (via SCSI).  

OMI's program Disk to Disk (excuse my type before hand) digitally reads 
the audio frames from the CD-ROM and converts it into one of the various 
sound formats popular on the Mac.  The AIFF and SDII formats are not 
compressed, they are full 16-bit formats.  They are also well documented, 
so it is easy to dissect and process these files, for whatever purpose 
you have in mind.

So, I am actually geting a true digital copy.  Even more accurate 
than if I was taking the S/P-DIF digital out on a CD player and sucking 
it into a computer, because the S/P-DIF digital out comes after the error 
correction and interpolation circuitry.  (Digital out on a CD player is 
not raw data off the disc.)

There is also no way that what I am doing could go through an 
analog stage because there is no audio connection between my Mac and
the CD-ROM.

> 
> You wouldn't be able to tell by listening, but it would certainly throw
> a wrench in the works if you tried to do steganography that way.

Actually, I use this setup to compare different pressing of one-off CDs,
we were trying to track down some glitches in the JVC CD-R mechanism when 
recording red-book audio disks.

I'm interested in persuing this further, it would be real intersting to
produce some audio disks with embedded information.  Let me know if you
are interested.

---
Rusty H. Hodge, Cyberneticist  <rustman@netcom.com> 


-------- Mystery Message #2:

> A set of remailers isolated from a restriction cooperative is a fully
> operative set of remailers.  Adding them to the killfile doesn't
> prevent these remailers from directly posting and directly mailing.

But it restricts the political heat from wide-open remailing to
those remailers who accept it.  This isn't ideologically pure,
but it might let more people run remailers in the face of people
like Detweiler (who has already attacked one and likely two
remailers).

   Eli   ebrandt@jarthur.claremont.edu