Method and apparatus for reading machine-readable symbols by employing a combination of multiple operators and/or processors

摘要

A method and apparatus for reading data collection symbols initially samples and preferably stores an image of light reflected from the symbol. An initial portion of the symbol in the stored image is located and multiple reading techniques are performed based on the stored symbol image and the located portion. Several output signals are produced from the multiple reading techniques, and one of the output signals is selected as a decoded signal that represents the data encoded in the symbol. The multiple reading techniques can be multiple reading methods performed substantially simultaneously with each other (on one or more processors), a single method performed multiple times and at multiple locations within the stored symbol image, or each reading method can be broken down into constituent modules, and like modules grouped into sets.