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Thread-Topic: TIFF validation
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From: "Loygorri, Fernando" <FLoygorr@inovant.com>
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Subject: [Tiff] TIFF validation
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Date: Wed, 9 Jun 2004 07:41:34 -0700
X-UIDL: 2c8f13a1b886b20c6e604cca902dae80

I have some questions regarding validation of TIFF files.

Page 21 of the 6.0 specification indicates that the type of
the ImageWidth field is "SHORT or LONG". To me, this seems to
indicate that if I'm validating a TIFF file and I find that
the ImageWidth field is of type BYTE I must flag the file as
not valid.

On the other hand, page 16 of the same document says: "TIFF
readers should accept BYTE, SHORT, or LONG values for any
unsigned integer field." To me, this seems to indicate that
in the example above I must consider the file valid.

But, then, why does the document explicitly exclude BYTE as
a legal option in the definition of the ImageWidth field (and
many others)?

I'm aware that "should" implies a recommendation (page 12);
does this mean that the note on page 16 has no bearing on the
validity of a TIFF file and it just exhorts writers of viewing
software to try to do the best they can when faced with a
malformed TIFF file?

Comments?

-- 
FGL
 
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