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Cognex Mobile Barcode Scanner SDK
DotCode

What is DotCode?

 

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The DotCode barcode symbol type is a public-domain optical data carrier designed to be reliably readable when printed by high-speed inkjet or laser dot technologies using codes with dots. Thus real-time data like expiration date, lot number, or serial number could be applied to products in a machine-readable form at production line speeds.

Why use DotCode?

DotCode’s flexibility and high error correction capabilities make it appealing to industries that require security and durability from the barcodes they use. For instance:

  • Major manufacturers are adding it to products and packaging for track and trace and workflow management solutions;
  • Major shipping and postal organizations have begun utilizing it on shipping labels as they can withstand ‘abuse’ during the shipping process and still be easily scanned;
  • Major CPGs recognize their ability to support anti-theft and counterfeiting initiatives because it is difficult to duplicate.

How is DotCode used?

A dot code, generically, is a type of barcode that encodes data in an array of nominally disconnected dots at chosen sites within a regular grid of possible locations. DotCode is a dot code whose array is rectangular in shape, of height H (rows) and width W (columns), with just half of the possible dot locations made available for printing, as the dark squares on a checkerboard

 

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and with about 56% of those dot locations eventually printed following the data-encoding rules

 

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Unlike other dot codes and all other matrix symbologies, this results in dots that are aligned on a grid diagonal to the edges of the rectangular outline of the symbol.

The sum of H and W must be odd; in other words either H or W must be an odd value and the other even. In some applications, the height H will be fixed and the width W will vary with data content, or vice versa, creating ribbon-like symbols appropriate to many high-speed dot printing methods. In other applications the aspect ratio of H and W can remain roughly fixed, both dimensions varying with data contained in a continuum of symbol sizes. Two-dimensional image readers can auto-discriminate all such symbols.

Logically, DotCode employs message encoding originally inspired by Code 128 and strengthened by Reed-Solomon error correction. Like Code 128, a proper subset of symbols is set aside for GS1-formatted data messages. It is designed, both graphically and logically, to tolerate missing, extra, or poorly-placed dots without sacrificing reading integrity.

Manufacturers of barcode equipment and users of the technology require publicly available standard symbology specifications to which they can refer when developing equipment and application standards. The publication of standardized symbology specifications is designed to achieve this.

How do we help developers using DotCode?

The Cognex Mobile Barcode Scanner SDK supports DotCode detection, enabling developers to gather relevant workflow and application data into their barcode scanning apps. You can download the SDK for free by registering on the Cognex Mobile Barcode Developer Network. In addition, the Barcode Scanner SDK supports a broad range of symbologies to meet your growing development needs.

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