# Re: make backend work on usb

From: msitkows@au1.ibm.com
Date: Sun Feb 06 2000 - 15:30:15 PST

- Next message: David Mosberger-Tang: "test 2"
  - Previous message: Oliver Neukum: "Re: make backend work on usb"
  - Maybe in reply to: Oliver Neukum: "make backend work on usb"
  - Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

  From what I've heard, the scanning head reads two adjacent pixels at a
  time, and then moves on by two positions. One data stream is all the odd
  pixels, the other is all the even pixels. This means the mechanism can be
  twice as coarse as the true resolution. HP has a fancy name for it, which I
  forget.
  Sorry I can't give you any more information. I got this from someone at HP,
  whose main specialty actually wasn't scanners.

  Mark
  ------------------------------------------------------------------------
  Mark Sitkowski ~{笑比哭好~}!
  14 Loddon Street
  Box Hill North, Victoria 3129
  ------------------------------------------------------------------------
  Phone: (613-9) 897-1375 ~{给我打电话~}!
  Fax: (613-9) 897-1376 E-mail: marks@iaccess.com.au
  Mobile: 0413-890-777
  Web : http://www.angelfire.com/de/designsim
  http://www.asiafind.com/sites/designsim
  ------------------------------------------------------------------------

  Am Son, 06 Feb 2000 schrieben Sie:
  > Oliver Neukum <Oliver.Neukum@lrz.uni-muenchen.de> on 07/02/2000 05:32:15
  >
  > >>The scanner reports two sources of data. I am not sure
  > >>whether I am reading from the correct one, or even if I need to do some
  > >>weirder stuff.
  > ......
  >
  > >>I am going to try to read from the other source, unless I get better
  > ideas.
  > >>I'd appreciate links to tools. I know C but neither USB nor scanners.
  > >>Please, please suggestions !?
  >
  > I've been told that the reason you're seeing this, is that HP scanners
  use
  > two interpolated sources of scan data, to double the resolution (this
  could
  > be wrong, but it makes sense...).

  Is that true for Microtek, too ?

  > If this is the case, then you need to read both data streams, and
  > interpolate the pixels - otherwise, you'll get a picture which looks
  almost
  > correct - but not quite...

  But what would I want to read an interpolated stream for?
  In addition I get no data at all.
  Could you please elaborate ?
  >
  > --
  > Hope this helps,
  > Mark
  > --
  > Source code, list archive, and docs: http://www.mostang.com/sane/
  > To unsubscribe: echo unsubscribe sane-devel | mail majordomo@mostang.com

      --
      Source code, list archive, and docs: http://www.mostang.com/sane/
      To unsubscribe: echo unsubscribe sane-devel | mail majordomo@mostang.com
      --
      Source code, list archive, and docs: http://www.mostang.com/sane/
      To unsubscribe: echo unsubscribe sane-devel | mail majordomo@mostang.com

  - Next message: David Mosberger-Tang: "test 2"
  - Previous message: Oliver Neukum: "Re: make backend work on usb"
  - Maybe in reply to: Oliver Neukum: "make backend work on usb"
  - Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

  This archive was generated by hypermail 2b29 : Sun Feb 06 2000 - 15:35:45 PST