Hand-supportable image-based bar code symbol reader employing helically-sweeping feature-extraction analysis on a captured digital image of an object referenced from the center thereof

摘要

A hand-supportable digital imaging-based bar code symbol reader comprises: an automatic object presence detection subsystem; an image formation and detection subsystem; a LED-based illumination subsystem having a wide area illumination mode of operation; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; an image-processing bar code symbol reading subsystem; an input/output subsystem; and a system control subsystem for controlling each of the above-described subsystems. The image-processing bar code symbol reading subsystem performs helically-sweeping feature-extraction analysis on a captured digital image of an object referenced from the center thereof, so as to enable the rapid reading of a bar code symbol graphically represented therein, using advanced image-processing based bar code reading techniques.