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Centering
Use Centering to narrow the image scanner’s field of view to make sure the
image scanner reads only those bar codes intended by the user. For instance,
if multiple codes are placed closely together, centering will insure that only the
desired codes are read. (Centering can be used in conjunction with Aimer
Delay, page 4-12, for the most error-free operation in applications where
multiple codes are spaced closely together. Using the Aimer Delay and
Centering features, the image scanner can emulate the operation of older
systems, such as linear laser bar code image scanners.)
In the example below, the gray area is the full image scanner field of view and
the white area is the centering window. Bar Code 1 will not be read, while Bar
Code 2 will be.
The default centering window is a 128x96 pixel area in the center of the image
scanner’s field of view. The following diagram illustrates the default top, bottom,
left, and right pixel positions, measured from the top and the left side of the
image scanner’s field of view, which is 640 by 480 pixels.
If a bar code is not within the predefined window, it will not be decoded or output
by the image scanner. If centering is turned on by scanning Centering On, the
image scanner only reads codes that intersect the centering window you specify
using the Top, Bottom, Left, or Right bar codes.
Bar Code 1
Bar Code 2
0
100%
100%
Default
Center
40% 60%
40%
60%
Left
Right
Botto
To