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:
May. 19, 1998
Filed:
Mar. 07, 1996
Marcus A Smith, Boise, ID (US);
Jeffrey L Trask, Boise, ID (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A software/firmware based method for determining gray level values to be assigned to a binary pixel image initially creates a linked list of templates, each template associated with a gray level value to be assigned to an image pixel value. Each template may include a central pixel value and plural neighbor pixel values or just plural neighbor values. However, each template is a listing of entries of template pixel values that are generally arranged in increasing concentric circles about the central pixel value. Each template entry includes a field for a template pixel value, a field for a template pixel address and a link field for a next template entry, in the event of a non-match determination between the associated template pixel value and an image pixel value. The method selects an image pixel window from the binary image and compares a central image pixel in the window with a logically, correspondingly located template pixel value. If a match is found, a next image pixel is compared against a next template entry to determine if a match occurs. This procedure continues, assuming matches are found, until all entries in the template have been tested and found to match, in which case, the central pixel of the image pixel window is changed in accordance with the gray level value associated with the matching template. If, at any time, a non-match occurs, the procedure moves to a linked template entry and the comparison procedure continues in another template. The invention enables a binary search to be executed which identifies a matching template (if any) after considering, on the average, between 5 to 10 entries.