Omnidirectional bar code reader using virtual scan of video raster scan memory

Abstract

Abstract An omnidirectional bar code reader uses a virtual scan of raster scan digital image memory to create the equivalent scanning pattern of a mechanical laser scanner. A two dimensional image of bar code symbol at any random orientation is captured in a memory. In one embodiment, the image memory is scanned to create a virtual scan equivalent to the scan pattern of a laser scanner. In another embodiment, the image memory is divided into plurality of memory segments, and simultaneous virtual scan is provided in each of the respective memory segments. In yet another embodiment, the memory is divided into a plurality of overlapping memory segments and simultaneous virtual scan is provided in each of the respective overlapping memory segments. The overlap between the memory segments is made large enough so that a bar code symbol of the expected size will be entirely included in one or the other of the overlapping memory segments. Thus, the boundary problem between memory segments is resolved and it is not necessary to concatenate partial scans between adjacent memory segments. The segmented scan may be achieved using an interleaved memory storage arrangement.

Inventors

• 👤 Donald G. Chandler
• 👤 Eric P. Batterman

Bibliographic Details