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From: John M Davison <davisonj@ecn.purdue.edu>
Subject: Question About Separated TIFF Images
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Date: Fri, 16 Sep 1994 02:17:07 -0500 (EST)
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        Page 69 of the TIFF 6.0 Specification says that "In a separated image,
each pixel consists of N components.  Each component represents the amount of a
particular ink that is to be used to represent the image at that location..."
Does this mean that there can be no extra samples in a separated image?

        Further down on the page, the Specification says "BitsPerSample =
8,8,8,8 (for CMYK).  SHORT.  For now, only 8-bit components are recommended.
The value "8" is repeated SamplesPerPixel times."  This raises the following
questions:

          1. "BitsPerSample = 8,8,8,8 (for CMYK)".  Does this mean
             that CMYK images cannot have extra samples?  What about
             non-CMYK separated images?

          2. "For now, only 8-bit components are recommended."  Does
             this mean that extra samples must be confined to 8 bits
             too?

          3. "For now, only 8-bit components are recommended."  Are
             there any cases in which 8-bit components are
             recommended but not required?  Must extra samples
             (assuming one can have them) be confined to 8 bits too?
-- 
John Davison
Electronic Mail: davisonj@ecn.purdue.edu
WWW Home Page: <http://en.ecn.purdue.edu:20002/~davisonj/HomePage.html>

