Message-ID: 383E9791.CF0D4F5B@home.com
To: TIFF Mailing List <tiff@olympiakos.com>
Subject: Re: Alternative to LZW (was Re: tiffcp)
From: Frank Warmerdam <warmerda@home.com>
Date: Fri, 26 Nov 1999 09:22:09 -0500
References: <Your message of Thu, 25 Nov 1999 14:58:04 +0000 <3.0.5.32.19991125145804.00cd4d50@mailhost.cam.harlequin.co.uk> <3.0.6.32.19991126110033.00c67100@mailhost>
Sender: owner-tiff@olympiakos.com


John Aldridge wrote:
> 
> At 21:19 25/11/99 -0500, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >ZIP seems about the best
> >unpatented lossless method out there, so it's probably what would have
> >been adopted.
> 
> How about PNGs algorithm?  I'm not suggesting the interleaving stuff; but I
> thought the spatial filtering bits were important in order to get the best
> out of the subsequent ZIP style compression.
> 
> I'm fed up with not having a decent free lossless compression algorithm
> available for TIFF, too.  Is there some way this group can move things
> along?

John,

Well, I doubt there is much we can do to make a new compression format for
TIFF, and to expect to have it widely supported.  However, I would be game
to lift some code out of the PNG library to implement a new compression
type in TIFF.  Just keep in mind that it isn't going to be widely supported.

Later,

---------------------------------------+--------------------------------------
I set the clouds in motion - turned up | Frank Warmerdam, warmerda@home.com
light and sound - activate the windows | http://members.home.com/warmerda
and watch the world go round - Rush    | Geospatial Programmer for Rent

