4 - 12 2020/4820/4820 i User’s GuideCenteringUse Centering to narrow the image scanner’s field of view to make sure theimage scanner reads only those barcodes intended by the user. For instance, ifmultiple codes are placed closely together, centering will insure that only thedesired codes are read. (Centering can be used in conjunction with AimerDelay, page 4-11, for the most error-free operation in applications where multiplecodes are spaced closely together. Using the Aimer Delay and Centeringfeatures, the image scanner can emulate the operation of older systems, such aslinear laser barcode image scanners.)In the example below, the gray area is the full image scanner field of view andthe white area is the centering window. Barcode 1 will not be read, whileBarcode 2 willbe.The default centering window is a 128x96 pixel area in the center of the imagescanner’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 imagescanner’s field of view, which is 640 by 480 pixels.Barcode 1Barcode 20100%100%DefaultCenter40% 60%40%60%LeftRightBottomTop
