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From: lamont@lava.net (Rick LaMont)
Subject: Varying BitsPerSample
To: tiff@olympiakos.com
Date: Tue, 3 Oct 2000 10:44:11 -1000 (HST)
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There was a discussion on a newsgroup recently about having TIFF files
with different data formats per channel.  For example, 8-bit RGB with
a 32-bit Z channel.  Some thought that the TIFF format does not allow
this but then Derek Kusiak wrote:

> Unless I'm misunderstanding what the TIFF 6.0 spec says, that's not
> true:
> 
> "Note that this field [BitsPerSample] allows a different number of bits
> per component for each component corresponding to a pixel. For example,
> RGB color data could use a different number of bits per component for
> each of the three color planes." (p.29)

Is there a limitation in libtiff that prevents exploitation of this
section of the spec?

I'm interested in interpretations of the spec, pros/cons of this feature,
limitations and workarounds.

Thanks,


Rick LaMont
Dot C Software, Inc.
