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Date: Thu, 12 Feb 2009 17:56:50 -0600 (CST)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Philip Watkinson <pwatkins@crawfordtech.com>
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Subject: Re: [Tiff] warning and errors
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On Thu, 12 Feb 2009, Philip Watkinson wrote:

> We want to use Libtiff in a production evironment. We don't want
> warnings/error messages unless there is a critical error (the image is
> corrupt).
>
> 1. Is there a listing of warnings which indicate that the image is corrupt?
> 2. If Libtiff generates an error, can I assume it is a critical error?

TIFF is a very flexible format.  There are proprietary usages of TIFF 
which require special tags in order for the proprietary software to be 
able to read the file correctly.  If a program using libtiff opens one 
of these files then the result may be gibberish.  However, the user is 
likely to see a wrong looking image.

In my experience, it is safe to simply ignore libtiff warnings most of 
the time.

If libtiff generates an error then something is severely wrong with 
the file, there is a bug in libtiff, or there is a limitation in the 
run-time environment (e.g. not enough memory).  Errors are serious.

Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/

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