Path: utzoo!attcan!uunet!van-bc!tessera!jtc
From: jtc@tessera.uucp (J.T. Conklin)
Newsgroups: comp.graphics
Subject: Re: Gif to IFF
Keywords: aspect ratio information required for maximum portability
Message-ID: <1989Oct21.235312.416@tessera.uucp>
Date: 21 Oct 89 23:53:12 GMT
References: <1198@clinet.FI> <390039@hpfcdq.HP.COM> <4608@mentor.cc.purdue.edu>
Reply-To: jtc@tessera.UUCP (J.T. Conklin)
Organization: Tesseract Communications, Burnaby, B.C., Canada
Lines: 22

In article <4608@mentor.cc.purdue.edu> ahg@mentor.cc.purdue.edu (Allen Braunsdorf) writes:
>TIFF	A very flexible image storage format.  Files contain a small header
>	and then a directory of tags.  These tags describe attributes
>	of the image.  By adding tags, the format can be extended.
>
>	TIFF is used primarily for scanners and image processing programs
>	on large microcomputers ("workstations", if you insist) and some
>	personal computers.  With the addition (and strict adherence to)
>	an aspect ratio tag, this format could be used most anywhere.  It
>	just takes a lot of code to do right.

TIFF doesn't have an aspect ratio tag because it doesn't need one.
It stores XResolution, YResolution, and ResolutionUnit as separate
tags.

The aspect ratio is computed by dividing the XResolution by YResolution.

    --jtc

-- 
J.T. Conklin
	...!{ubc-cs,uunet}!van-bc!tessera!jtc