# Re: [BUG] Epson 1640SU, xsane preview problem]

From: Oliver Rauch (oliver.rauch@rauch-domain.de)
Date: Fri May 25 2001 - 01:38:56 PDT

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  Jean-Luc Coulon wrote:

  > > if (quality <= min_quality+20)
  > >
  > With this change, it works !

  Fine. Although this is not the correct way to solve it.

  >
  > Now, back to the "resize" function.
  > Basically it works : I was confused with the previous problem.
  > But the "autoselect" button does not work as expected.
  >
  > If I place a drawind in the middle of the bed, any size selected, only
  > the bottom line is at the right place, the other ones are at the
  > top/left/right ends of the format.
  >
  > Why is the color set to 25 instead of 55 in xsane-preview.c, line 5505 ?
  > (this has no effect for my problem)

  Does your scanner use a black or a white background or anything else?

  The 25 is a bug, I will replace it by 55.

  The routine does search pixels that differ from the background. The backround
  has to be black or white. When one pixel is found that differs with a brightness
  of about 20% of the visible range the frame position is found.

  The test is done with the gamma corrected preview, so you will get different results
  with different gamma/brightness/contrast settings.

  Bye
  Oliver

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