Points based handwriting recognition system

• US 6,731,803 B1
• Filed: 07/12/2000
• Issued: 05/04/2004
• Est. Priority Date: 07/12/1999
• Status: Expired due to Fees

• Current Assignee: Advanced Recognition Technology
• Original Assignee: Advanced Recognition Technology
• Inventors: Aviad, Boaz, Aharonson, Eran
• Primary Examiner(s): MARIAM, DANIEL G
• Application Number:
  US09/614,860
• Time in Patent Office: 1,392 Days
• Field of Search: 382/119-123, 382/173, 382/181, 382/184-190, 382/201, 382/202, 382/205, 382/209, 382/217, 382/218, 382/229, 382/305, 382/313-315, 178/18.01, 178/18.03, 178/19.01, 178/19.04, 345/169, 345/173, 345/179, 345/189
• US Class Current: 382/187
• CPC Class Codes: G06V 30/1423 the instrument generating sequences of position coordinates corresponding to handwriting preprocessing or recognising digital ink G06V30/32

Abstract

A points based handwriting recognition system is suitable for hand held processor implemented devices with small touch pad writing surfaces. The writing surface is divided into a grid by a number of spaced discrete points. The user is instructed to write, as by a stylus, characters such as letters, numbers or symbols with the writing path extending through a predetermined sequence of the points which define the grid. The stylus must pass sequentially within a specified distance of mandatory points for processor recognition of each written character and may additionally pass within a predetermined distance of optional points.

Claims

1. A handwriting recognition system for use in inputting data to a processor implemented device, the recognition system including a writing surface comprising a matrix of adjacent x, y coordinates, the writing surface having a grid defined by a plurality of discrete points spaced from one another by a discernable distance, the distance comprising a plurality of adjacent x, y coordinates, the processor being operatively connected to the writing surface, the processor being programmed to transform the sequential order of x, y coordinates the path a handwritten character passes through when written on the writing surface to a sequential order of grid points, the processor accessing a model library of sets of sequential point descriptions, each set having a value corresponding to data to be input, the processor being programmed to compare the transformed sequential order of grid points with the order of points of the model sets, the processor being programmed to determine which model set matches the transformed sequential order of grid points and to set a recognition to the value of the matching model set.

2. A handwriting recognition system as constructed in accordance with claim 1 wherein the writing surface comprises a touch pad.

3. A handwriting recognition system as constructed in accordance with claim 1 wherein the grid is defined by nine discrete grid points arranged in three columns of three grid points each.

4. A handwriting recognition system as constructed in accordance with claim 3 wherein the grid points are equidistantly spaced from one another.

5. A handwriting recognition system as constructed in accordance with claim 1 wherein the grid is defined by twelve discrete grid points arranged in three columns of four grid points each.

6. A handwriting recognition system as constructed in accordance with claim 5 wherein the grid defines a horizontal base line beneath which depending portions of selected alphabet letter characters are written.

7. A handwriting recognition system as constructed in accordance with claim 1 wherein the sequential point descriptions of the model sets include optional points through which the path of the corresponding handwritten character may or may not pass, the processor determining which model set matches the transformed sequential order of grid points without requiring the transformed sequential order of grid points to include any of the optional points.

8. A handwriting recognition system as constructed in accordance with claim 7 wherein the model library of sets is stored in a memory.

9. A method of teaching a user of a portable processor implemented device to handwrite processor recognizable data entries, the method comprising the steps of:

a) providing a writing surface having a matrix of adjacent x, y coordinates,

b) superimposing a grid on the writing surface, the grid comprising a plurality of discrete points spaced from one another a discernable distance, the distance comprising a plurality of adjacent x, y coordinates,

c) instructing the user to write designated characters on the writing surface by traversing the grid in a path which passes through designated grid points in a designated sequential order of points in simulation of natural handwriting.

10. A method of teaching in accordance with claim 9 wherein the user is instructed that the path may but is not required to pass through selected optional points.

11. A method of teaching in accordance with claim 9 wherein the plurality comprises twelve points arranged in three columns of four grid points each, the grid defining a horizontal base line, the user being instructed that the path forming selected alphabetic letter characters is to extend below the baseline.

12. A method of generating processor recognizable handwritten characters, the method comprising the steps of:

a) providing a writing surface having a matrix of adjacent x, y coordinates,

b) positioning a grid on the writing surface, the grid being defined by a plurality of discrete points spaced from one another a discernable distance, the distance comprising a plurality of adjacent x, y coordinates,

c) storing a library comprising a plurality of model sets, each model set comprising a plurality of sequential points, each model set having a corresponding data entry value,

d) writing a selected character on the writing surface along a path sequentially passing through selected points,

e) transforming ascertaining the sequential order of x, y coordinates through which the written path extended into a sequential order of grid points,

f) accessing the stored model sets, and

g) comparing the transformed sequential order of grid points with the plurality of sequential points of accessed model sets.

13. A method of generating processor recognizable handwritten characters in accordance with claim 12 further including the step of:

h) ascertaining the data entry character value of a matching model set and inputting such data entry value into the processor.

14. A method of generating processor recognizable handwritten characters in accordance with claim 12 wherein selected model sets include optional points within the sequential order, the step of comparing including accepting as a match, a transformed sequential order of grid points which does not include one or more of the optional points of a model set.

15. A method of generating processor recognizable handwritten characters in accordance with claim 12 wherein the grid comprises twelve points configured in three columns of four points each, the grid defining a baseline, the step of writing a selected character on the writing surface including writing an alphabetic letter character having a depending portion along a path which extends below the baseline.