Re: tiff parsing problem

Peter Nelson (mailto:pnelson@MTHOLYOKE.EDU)
Fri, 9 Oct 1998 17:32:50 -0400

Message-Id: <199810092137.OAA22604@dns.ccit.arizona.edu>
Date:         Fri, 9 Oct 1998 17:32:50 -0400
From: Peter Nelson <mailto:pnelson@MTHOLYOKE.EDU>
Subject:      Re: tiff parsing problem
To: mailto:IMAGELIB@LISTSERV.ARIZONA.EDU

I am still working on the TIFF problem, and thank those who have
contributed suggestions and comments (as contradictory as they may be).
For now I want to follow up on something David Adams wrote:

<snip>

> This leads me on to a query regarding LZW.
>
> Is this a useful file format ?
> the amount of compression is little ca10%
> There isnt a great deal of saving cost wise.
> (we save 5,000 uncompressed tiff files a year, using lzw we would
> save $30 on CD costs, whoppee)
>
> Is it going to prove a problem in the distant
> future as far as readablity goes ? 50+ years from now.
>
> We are sticking to raw tiff format.

LZW works a lot better for me. I am not getting 10% file compression with LZW, as you are. It's between 87-93%! (I.e., I have an uncompressed TIFF of 824 KB; with LZW it is 101KB. Another uncompresed file is 888 KB, while with LZW it is only 63 KB.) LZW would seem to me to be a significant space-saver, regardless of plummeting storage costs. How can we be so far off in our compression savings?

..................................................................... Peter Nelson mailto:pnelson@mtholyoke.edu Five College Archives Digital Access Project c/o Mount Holyoke College Archives http://clio.fivecolleges.edu South Hadley, MA 01075 (413) 538-3020

Internet is a good way to get on the Net. - Bob Dole ......................................................................

On Fri, 9 Oct 1998, David Adams wrote:

> This leads me on to a query regarding LZW.
>
> Is this a useful file format ?
> the amount of compression is little ca10%
> There isnt a great deal of saving cost wise.
> (we save 5,000 uncompressed tiff files a year, using lzw we would
> save $30 on CD costs, whoppee)
>
> Is it going to prove a problem in the distant
> future as far as readablity goes ? 50+ years from now.
>
> We are sticking to raw tiff format.
>
>
>
>
> David Adams
> Copying Services - Team Leader
> Visit "Timeframes" at http://timeframes.natlib.govt.nz/
> "New Zealand's leading source of heritage images"
>