| abstract |
A hand-supportable digital imaging-based bar code symbol reading device comprises: an IR-based object presence and range detection subsystem; a multi-mode area-type image formation and detection subsystem having narrow-area and wide area image capture modes of operation; a multi-mode LED-based illumination subsystem having narrow-area and wide area illumination modes of operation; an automatic light exposure measurement and illumination control subsystem; an image capturing and buffering subsystem; a multi-mode image-processing bar code symbol reading subsystem; an input/output subsystem; a manually-activatable trigger switch; and a system control subsystem integrated with each of the above-described subsystems. The multi-mode image-processing based bar code reading subsystem has a modular image-processing architecture constructed from four major image processing modules, namely: a tracker module, a finder module, a marker module, and a decoder module. These image processing modules enable the multiple modes of operation of the multi-mode image-processing based bar code reading subsystem. |