Message-ID: 3.0.6.32.20000124105020.00a188f0@mailhost
To: tiff@olympiakos.com
Subject: RE: Unicode build of libtiff?
From: John Aldridge <john.aldridge@informatix.co.uk>
Date: Mon, 24 Jan 2000 10:50:20 +0000
In-Reply-To: <900805FA5A6FD31180BA009027786C2F05436F@ATLEX01>
Sender: owner-tiff@olympiakos.com


At 09:00 21/01/00 -0500, "Martinez, Max" <max.martinez@erdas.com> wrote:
>Indeed UTF-8 is only compatible with ASCII, but would that
>make it unwise to say that the type formerly known as
>ASCII has been redefined to be UTF-8?

I didn't say or imply this.  When I wrote

>> Not so!  UTF-8 is different for characters >127...

I was responding to the specific claim

>> >    Nope!   UTF-8 encoding is the same as ASCII for all values 
>> ><=255, so all Roman/Latin based language information would look and 
>> >act the same.

which is wrong.

>How would this
>break anything other than to have non-savvy apps display
>gibberish where they wouldn't have been able to
>display anything anyway?

Since you ask, however, I suppose it's possible that "common practice" is
to store characters encoded according to the current locale in these
fields.  This would result in, e.g., Greek TIFF files being illegible to
Japanese readers; but this might have been an acceptable limitation in
specific markets.  The spec prohibits this ("8-bit byte that contains a
7-bit ASCII code"), but it might work in practice.

Does anyone know whether this practice is used, and if so whether it is
common enough to worry about?
-- 
Cheers,
John

