METHODS AND APPARATUS FOR READING BAR CODE IDENTIFICATIONS

摘要

The invention provides methods and appartaus for analysis of images of two-dimensional (2D) bar codes in which a model' that has proven successful in decoding of a prior 2D image of a 2D bar code isutilized to speed analysis of images of subsequent 2D bar codes. In its various aspects, the invention can be used in analyzing conventional 2D bar codes, e.g., those complying with Maxicode and DataMatrix standards, as well as stacked linear bar codes, e.g., those utilizing the Codablock symbology. Bar code readers, digitaldata processing' apparatus and other devices according to the invention be used, by way of non-limiting example, to de­- code bar codes on damaged labels, as well as those screened, etched, peened or otherwise formed on manufactured articles (e.g., from semiconductors, to airplane wings). In addition to making bar code reading possible under those conditions, devices utilizing such methods can speed bar code analysis in applications where multiple bar codes of like type are read in suc­cession and/or are read under like circumstances e.g., on the factory floor, at point-of-sale locations, in parcel deliver and so forth. Such devices can also speed and/or make' possible bar code analysis where in applications where multiple bar codes read from a single article e.g., as in the case of a multiply-encoded airplane propellor or other milled parts. The inven­tion also provides methods and apparatus for optical character recognition and other image based analysis paralleling the above.