Patent ID: 6508404
Filing Date: 2003-01-21
Classification: G06K

Abstract:
A device for locating a bar code symbology on a presented surface, the device having a light source for illuminating the surface; a detector for generating a light intensity signal that corresponds to transitions in reflected light from the surface; and a processor for processing the light intensity signal to identify the potential location of the bar code symbology; the processor comprising:a signal generator for generating, from the light intensity signal, a series of counts which identify transitions in the light intensity; a locator for determining a location of each of the counts; a separator for separating the series of counts into alternating odd and even counts; a multiplier for simultaneously multiplying each of the separated counts by a plurality of predetermined values to simultaneously generate a corresponding plurality of odd and even comparison values; a comparator for comparing said plurality of odd comparison values to a subsequent odd count, and said even comparison values to a subsequent even count, determining whether a comparison is a valid match and outputting a valid match indicator for each valid odd/even match; and a combiner for receiving the comparator outputs and, upon detection of consecutive odd/even comparator outputs, generating a potential bar code match indicator; whereby the likelihood of the existence of the bar code symbology at a certain location increases with an increasing frequency of potential bar code match indicators.