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Date: Sat, 25 Aug 2007 17:29:02 -0500 (CDT)
From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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Subject: [Tiff] 24-bit samples in TIFF
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Status: RO

Due to statements in Chris Cox's draft specification, it seems that 24 
bit values are now officially swapped to match the "host" endianness 
(a recent libtiff change).  However, there is no "host" endianness for 
24 bits for any known host on the planet since CPUs (other than 
perhaps some exotic DSP) do not have 24-bit words.  I have not checked 
to see what libtiff is really doing, but it seems to me that it is 
best for the libtiff API user if 24-bits are presented in big-endian 
network-byte-order and not swapped into an order which does not help 
any type of host.  If libtiff needs to swap data before it goes into 
the file in order to be complaint with Chris Cox's draft specification 
(and Photoshop CS2), then that is fine.

Opinions?

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

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