Browse Prior Art Database

White Scanner Drum With Black Stripe

IP.com Disclosure Number: IPCOM000101118D
Original Publication Date: 1990-Jun-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Hawk, JI: AUTHOR [+2]

Abstract

Existing feedthrough document scanners utilize either a 100% black or a 100% white background. Additionally, either a mechanical or a photoelectric means of beginning/end of document is used.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 82% of the total text.

White Scanner Drum With Black Stripe

       Existing feedthrough document scanners utilize either a
100% black or a 100% white background.  Additionally, either a
mechanical or a photoelectric means of beginning/end of document is
used.

      There is a requirement that the full document be captured in
both the vertical and horizontal axes, due to mechanical inaccuracies
of the feed mechanism and beginning/end of document detection
mechanism, background data will be captured and subsequently stored
as part of the image.  If an all black background is used, black
"borders" will appear in the vertical axes because the scan must go
beyond the edges of the document.  If a white background were used,
the borders would be white, but it would then be impossible to detect
the start and end of a document electronically because most documents
are also white.

      The invention disclosed herein enables the leading and the
trailing edges of a document to be electronically detected so as to
not rely upon the inaccuracy of a mechanical or photoelectric
detector.  Referring to the figure, three software loops in the image
detection program are used for detecting the transition from black to
white or from white to black.  Software loops 1 and 3 are looking for
a non- white area and software loop 2 is looking for a non-black
area.  When either of these three loops detect a change, the reading
and storing of the data will start for the images to be scanned from
the docu...