Importance

Loading Importance Indicators...

Abstract

A bar code symbol picked-up by a two-dimensional image pickup device is stored in a frame memory. A data processing unit automatically recognizes whether the bar code symbol is present or not, based on the information stored in the frame memory, that is, the image pickup data. If the bar code symbol is present, the information of the bar code symbol projected on a photoelectric conversion surface of the two-dimensional image pickup device is read and decoded to the original information. The bar code symbol can be recognized automatically by the following methods of monitoring a variation in density of the image pickup data, monitoring a spatial frequency component of the image pickup data, monitoring whether a predetermined bar code pattern is formed in the image pickup data, monitoring widths of bars and spaces in the image pickup data, monitoring the number of edges of bars and spaces in the image pickup data, monitoring a correlation among the image pickup data obtained by a plurality of image pickup operations of the image pickup device, etc.

Loading the Abstract Image...

First Claim