Pattern generation method for registering handwriting

• US 5,040,222 A
• Filed: 12/14/1989
• Issued: 08/13/1991
• Est. Priority Date: 04/03/1989
• Status: Expired due to Term

• Current Assignee: Cyber SIGN Japan, Inc.
• Original Assignee: CADIX, Inc.
• Inventors: Muroya, Masami
• Primary Examiner(s): Moore, David K.
• Assistant Examiner(s): COUSO, YON JUNG
• Application Number:
  US07/450,551
• Time in Patent Office: 607 Days
• Field of Search: 382/3, 382/13, 382/24, 382/34, 382/52, 382/30, 382/14
• US Class Current: 382/123
• CPC Class Codes: G06V 40/30 Writer recognition; Reading and verifying signatures
• CPC Class Codes: G07C 9/35 by means of a handwritten signature

Abstract

A pattern generation method for registering handwriting and a method for updating same that facilitates the obtaining of a registration pattern that reflects accurately the characteristics of an individual handwritten signature. Dynamic programming matching is used to obtain a cumulative error among a plurality of input patterns in the form of a distortion function, and this distortion function is used for shape averaging and time distortion averaging of input patterns.

Claims

1. A pattern generation method in which a time axis is employed for registering a handwritten character with a stroke action, comprising the steps of:

multiple inputting of handwritten characters in the form of coordinate and writing pressure three dimensional time series information;

normalizing the position and size of multiple handwritten character patterns thus input;

calculating a distortion function for selecting a desired pattern from the multiple input patterns as a reference pattern and obtaining a time distortion function between the reference pattern and other input patterns using dynamic programming matching;

using the distortion function for time axis correction of the time axis of each input pattern;

shape averaging the time axis corrected multiple input patterns;

distortion averaging the multiple distortion functions; and

time distortion correction of the time axis of the shape averaged patterns, using the distortion function average;

whereby the registration pattern is obtained from the distortion function derived shape average and time distortion average.

2. A pattern generation method according to claim 1, wherein the registration pattern is updated in accordance with changes in input patterns corresponding to time-based changes in a handwritten character input pattern, comprising:

forming a multiplicity of handwritten character input patterns from an existing registration pattern and new input patterns; and

giving a prescribed weighting to the existing registration pattern and the input patterns and performing each of the steps of the method.