Re: data compression and color management
Re: data compression and color management
- Subject: Re: data compression and color management
- From: email@hidden
- Date: Wed, 8 Nov 2000 18:43:23 EST
In a message dated 11/8/00 1:39:39 PM, email@hidden writes:
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Can anyone comment on how image data compression can be used in a color
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managed
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workflow?
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I'm wondering specifically about two scenarios - one in which the scan
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includes
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an embedded profile, and is then compressed for later use. And another
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in which
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the data is transformed (either into Lab space or output space) then a
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profile
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is embedded, then the data is compressed.
Profiles are used by a CMM to convert pixel color numbers. If the numbers are
changed by lossy compression, the results will change as well. To tag a
profile is to define a relation to LAB (or XYZ) and it is assumed that what
came in will be the same going back out; but if it is comressed and changed
in the interum then it will not be identical on its return... but using lossy
compression denotes a willingness to accept non-identical results. It would
be quirks where color conversion exagerated JPG artifacts that would be the
biggest concern, similar to the enhancement of such artifacts by Genuine
Fractals.
C. David Tobie
Design Cooperative
email@hidden