The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 26, 1999
Filed:
Mar. 20, 1997
Jiangying Zhou, Plainsboro, NJ (US);
Daniel P Lopresti, Hopewell, NJ (US);
Abstract
A method of locating a machine-readable two dimensional marker, such as a barcode, in an image. An image of a medium containing the two dimensional marker is processed to generate a mask containing one or more filled regions each of which is sufficiently large to contain the predetermined dimensions of the marker. To generate the mask, small image areas having a first pixel polarity which are internal to larger image areas having a different pixel polarity are first filled with pixels having the same polarity as the surrounding larger image areas. A morphological opening operation is then performed on the filled image to leave only such filled regions as are equal in size or larger than the predetermined dimensions of the marker. After the mask has been generated, the mask is logically combined with the original image to extract one or more candidate regions. The candidate regions are then tested to determine whether or not a marker is present by one of several described methods, including, for example, by attempting to decode portions of each candidate region. Based upon the results of the testing, one or more candidate regions are selected for decoding.