Browse Prior Art Database

High Speed Pattern Matching for Optical Character Recognition Device

IP.com Disclosure Number: IPCOM000099647D
Original Publication Date: 1990-Feb-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 3 page(s) / 93K

Publishing Venue

IBM

Related People

Matsukawa, T: AUTHOR [+2]

Abstract

A optical character device is disclosed that it has the high speed pattern matching hardware with attribute key, distance calculation and sort.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 62% of the total text.

High Speed Pattern Matching for Optical Character Recognition Device

       A optical character device is disclosed that it has the
high speed pattern matching hardware with attribute key, distance
calculation and sort.

      The input image of a document obtained from a scanner device is
pre-processed by segmentation and normalization. Then features are
extracted from the pre-processed image and are stored into the input
feature pattern memory.  The features are used to reduce the number
of candidates rapidly and to arrive at the most likely candidate.
After this, the hardware calculates the distance between the input
feature and the standard template of characters.  At that time, the
high speed pattern matching can be done by the following method.
 1. Calculate the distance between the input pattern and the standard
template.  If the distance exceeds the threshold, the calculation is
stopped (Phase 1).
 2. Sort the results obtained from (Phase 1) in descending order of
distance (Phase 2).
 3. The sort data is fedback to the threshold value (Phase 3).
 4. There is a character attribute key in the input pattern and
standard template which indicates attributes such as numeric,
alphabetic, OCR-B, etc.  Phase 1, 2 and 3 are running only if these
attributes match.

      Fig. 1 shows the typical data flow of character recognition.
Fig.  2 shows the data format of the input feature pattern and
standard template.

      Figs. 3 and 4 show the hardware c...