Re: [Gimp-print-devel] Tests with Stylus 640

[Robert L K. <rl...@al...>]

   From: sh...@al...
   Date: Wed, 16 Feb 2000 16:32:26 +0900

   Scratch that.  It is a family photo, but the resolution isn't that low.
   There was a bug in unprint that was causing pixels to be put in slightly
   the wrong place, resulting in what appeared to be large scale pixelization.

He used a fairly new digital camera for this.

   With the current unprint, it unprints rather well.  Yet, I'm at a loss to
   explain the two vertical bars that appear on the image.

Interestingly enough, it looks half as wide as it should be.  I say
"interesting" because of Karl's experience of getting something that's
TWICE as wide as it should be.  So that suggests that our model of how
the printer works is wrong.

   If you run this through unprint -u, to unweave the softweaving you can see
   the origin of these features more clearly.  On some passes, there is a
   single pixel wide vertical bar.  The position of the bar is not the same in
   each pass, resulting in a multi-pixel wide vertical bar when the data is
   woven.

   I don't know if this is a bug in unprint, or due to some undocumented
   command effect that I haven't taken into account.  Anyone have any ideas?

I was going to wonder if it was a problem with the image, but that
doesn't look likely considering that that line appears in places where
there should be no ink at all.

-- 
Robert Krawitz <rl...@al...>      http://www.tiac.net/users/rlk/

Tall Clubs International  --  http://www.tall.org/ or 1-888-IM-TALL-2
Member of the League for Programming Freedom -- mail lp...@uu...
Project lead for The Gimp Print --  http://gimp-print.sourceforge.net

"Linux doesn't dictate how I work, I dictate how Linux works."
--Eric Crampton