[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: NTY compression proposal (fwd)
All editing errors are my own, I re-formatted the original text to better
address the points.
Forwarded message:
> Date: Sun, 18 Jan 1998 19:17:32 -0800
> From: Steve Schear <[email protected]>
> Subject: Re: NTY compression proposal
> Compression efficiency depends upon
> 1) the entropy of the input data
We are looking at selecting 100 64-bit keys out of a set of 2^64,
that is not a lot of opportunity there, given a random key generation
process, for a lot of commen patterns in the key set. If we don't have a
lot of commen patterns in the text we don't get a lot of compression.
> 2) the allowable losses
In this case we can't afford any loss.
> 3) finding an efficient algorithm to code for that entropy.
Which if we do the math requires something in the neighborhood of 33:1,
for a loss-less algorithm that's a pretty hurky boundary condition.
> I think I'm on fairly firm ground assuming that key data entropy is very=
> high and therefore little or no compressible is feasible.
My point exactly, which would lead us to the conclusion that our requirement
of a 33:1 compression factor is not realizable.
____________________________________________________________________
| |
| The most powerful passion in life is not love or hate, |
| but the desire to edit somebody elses words. |
| |
| Sign in Ed Barsis' office |
| |
| _____ The Armadillo Group |
| ,::////;::-. Austin, Tx. USA |
| /:'///// ``::>/|/ http://www.ssz.com/ |
| .', |||| `/( e\ |
| -====~~mm-'`-```-mm --'- Jim Choate |
| [email protected] |
| 512-451-7087 |
|____________________________________________________________________|