Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!well!chris
From: chris@well.UUCP (Chris Sears)
Newsgroups: comp.graphics
Subject: Re: Image file format discussion
Message-ID: <14203@well.UUCP>
Date: 22 Oct 89 02:00:17 GMT
References: <1198@clinet.FI> <390039@hpfcdq.HP.COM> <4608@mentor.cc.purdue.edu> <6040@pitt.UUCP>
Lines: 29

In article <6040@pitt.UUCP>, planting@hobbes.cs.pittsburgh.edu (Dr. Harry Plantinga) writes:
> In article <4608@mentor.cc.purdue.edu> ahg@mentor.cc.purdue.edu (Allen Braunsdorf) writes:
> 
> There is other information that should be stored with images but which
> I have not heard anyone mention.
> 
> _Big-endian vs. Little-endian_:  does 255 represent white or black?

By this do you mean byte ordering.  TIFF supports both Intel and Motorola
byte ordering.  "does 255 represent white or black?",  This is called
Photometric Interpretation in TIFF parlance.

> 
> _Primary colors_:  the wavelengths of the (R, G, and B) primaries used
> 
> _Gamma correction factor_:  Monitors, video cameras, and other

TIFF tags for primary chromaticities, white point are available.
For gamma, color response curves describe any sort of companding function
as a set of 3 16-bit lookup tables.

"Internal" compression schemes are also available.  The full TIFF 5.0
specification is available from Aldus.

And, best of all, an excellent public domain TIFF library written by
Sam Leffler is available via FTP from ucbvax.berkeley.edu.  It is very
easy to use and extend.

--Chris