From: "Perry E. Metzger" <perry@piermont.com>
Date: Mon, 8 Apr 1996 11:54:03 +0800
To: JonWienke@aol.com
Subject: Re: Spinners and compression functions
Message-ID: <199604072252.SAA29569@jekyll.piermont.com>
MIME-Version: 1.0
Content-Type: text/plain



[I've sent a fuller reply to Jon in private mail.]

JonWienke@aol.com writes:
> >Actually, it doesn't. The entropy present from a reasonable source
> >like keyclick timings is much much lower than the output of pkzip is
> >going to suggest to you.
> 
> I am not saying that the output of the compression function has 8 bits of
> entropy per byte, but rather that it will have a more consistent entropy
> level per byte than the input to the function.

What makes you think that? There is little to no cause to expect this
at all. I can think of a number of instances, like image data streams,
where this idea is completely unfounded for most conventional
compression techniques.

Perry