profile internals
profile internals
- Subject: profile internals
- From: "Daniel Lowicki" <email@hidden>
- Date: Tue, 25 Dec 2001 09:30:37 +0100
I am still missing out some information about profiles.
Is there a whitepaper which doesn't go as deep as to enable
me to programm my own profile but still gives me an insight
about the structure.
Some questions that come to my mind:
- In postings I read about A1B1 (etc.) tables. I am sure those are
the in/out tables of the rendering intents but where can I read
which one is which ?
- Since I only do one mesuring session all the vendors of profiling
software seem to brew their own soup. How do the in and out
tables of a profile differ after profiling? If there is only one set of
data why aren't they always symmetrical.
- How do the tables differ between rendering intents. Again I only
have one set of data so what happens with the data in the tables ?
Obviously they all have to be different.
- Does editing the whitepoint tag have any effect on the tables ?
Like .. if I edit the wp will there be an inconsistancy because there
are also white patches in the profile (tables) part?
- Is the table for the colorimetric intent actually RelCol with the wp
to be added in AbsCol transformations (which would mean the wp was
subtracted first) or is it AbsCol with the wp to be subtracted for RelCol.
- How is the wp tag generated .. since for example when measuring in
printopen the wp tag values differ from the value measured in the white patches.
What I expected to find in the first place was all the same values in all 6 tables
for the CMM to do the rest. But - obviously - for speed issues so much more
intelligence (!?) was put into the profiles that I find it hard to follow what's going on.
If there is no understandable documentation for this I'd appreciate it if anybody
could clear things up.
Merry Christmas
-- Daniel