Re: [Announce] WinSANE 0.1.0.0 Release
Matthias Fleischer (FLEISCHER@ito311.ito.uni-stuttgart.de)
Wed, 12 May 1999 13:36:58 CET
>
> White pixels (0) are still white pixels, while black pixels have the
> value of (240) since shifting left by 4 is like multiplying by 16. The
> only reason to multiply by 17 is to use the whole dynamical range
> (0-255) and is not related with the whiteness of pixels AFAIK.
>
IMO it does make a difference weather white is really white
(255) or light grey (240) once you print it out on paper.
You e.g. want to build a xerox copier program and tell the user to
set the gamma accordingly to get a good dynamic range. Now if the
backend does only send light grey for white areas he will never manage
to remove that gray shadow in the background no matter how hard he
tries.
Given he got an ink-jet that will cost him printing time and
will look nasty since you will always see those regular dots on
paper no matter how few they are. Even a value of 0xfff0 for 0xffff
gives a dot at every 64. pixel in each direction which is quite
obvious to the eye.
OK - if the real pixel depth can be queried that's probably more a
problem of the copier program.
OTOH I really just wanted to say that the documentation seems
to speak of a factor of 4 where 16 were meant (17 would be the
nitpicking value).
Matthias
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