[argyllcms] Re: Version 0.53 - Gamut mapping warning message.


It's been noted that V0.53 (and V0.52) sometimes emit
the following message when creating profiles or linking:

"Warning: Gamut mapping is non-monotonic!"

This seems to only happen when creating a gamut mapping for
a saturation intent. It basically means that the saturation
gamut mapping is not as smooth as it could be. I'm not sure
of the practical significance - the gamut boundary values
change a little more abruptly than I really like, but colors
with the gamut still seem to still behave reasonably, and the
generally expectation for saturation mapping is that saturation
is favoured over other factors (such as smoothness).

Now traditionally, Argyll's saturation intent has been smoother
than many other profiling systems, and I think I will bump up
the smoothness of the gamut mapping somewhat for the next release
to restore the behaviour.

[ This message seems to be a consequence of the changes I made
  in improving the accuracy of modelling the device characteristics
  in RSPL.

  If you are using the source, you can make the message go away,
  and improve the smoothness of the gamut mapping by changing
  smth from 2.0 to 30.0 at line 900 in gamut/gammap.c ]

Graeme Gill.

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