Method and apparatus for scaling handwritten character input for handwriting recognition

• US 20050152602A1
• Filed: 01/14/2004
• Published: 07/14/2005
• Est. Priority Date: 01/14/2004
• Status: Active Grant

• Current Assignee: Kyndryl Incorporated
• Original Assignee: International Business Machines Corporation
• Inventors: Chen, Yen-Fu, Dunsmoir, John W.
• Granted Patent: US 7,298,904 B2
• Time in Patent Office: Days
• US Class Current: 382/187
• CPC Class Codes: G06V 30/10 Character recognition
• CPC Class Codes: G06V 30/1423 the instrument generating sequences of position coordinates corresponding to handwriting preprocessing or recognising digital ink G06V30/32
• CPC Class Codes: G06V 30/166 Normalisation of pattern dimensions

Abstract

A method, computer program product, and a data processing system for scaling handwritten character input for performing handwriting recognition. A stroke parameter is derived from a handwritten character stroke and an input area is calculated in which the handwritten character stroke was supplied. The stroke parameter is scaled according to the input area.

Claims

1. A method for scaling handwritten character input for performing handwriting recognition, the method comprising the computer implemented steps of:

deriving a stroke parameter from a first handwritten character stroke;

calculating an input area in which the first handwritten character stroke was supplied; and

scaling the stroke parameter according to the input area.

2. The method of claim 1, wherein the step of deriving includes:

detecting a start point and an end point of the first handwritten character stroke.

3. The method of claim 1, wherein the input area bounds the first handwritten character stroke at coordinate extrema of the first handwritten character stroke.

4. The method of claim 1, wherein the step of deriving includes:

calculating a length parameter of the first handwritten character stroke.

5. The method of claim 4, wherein the step of calculating includes:

squaring the length parameter of the first handwritten character stroke.

6. The method of claim 1, wherein the step of scaling includes:

multiplying the stroke parameter with a ratio of a reference area to the input area.

7. The method of claim 1, further including:

determining coordinates of a start point and an end point of the first handwritten character stroke;

determining the coordinates of a start point and an end point of a second handwritten character stroke, wherein the step of calculating includes identifying coordinate extrema of the coordinates of the first handwritten character stroke and the second handwritten character stroke.

8. A computer program product in a computer readable medium for scaling a parameter derived from a handwritten character stroke comprising:

first instructions for determining a start point and an end point of a first stroke input into a computer interface, responsive to determination of the start point and the end point, calculating a stroke length parameter of the first stroke; and

second instructions for calculating an input area in which the first stroke was supplied and, responsive to calculating the input area, scaling the stroke length parameter of the first stroke according to the input area.

9. The computer program product of claim 8, wherein the input area bounds the first stroke at coordinate extrema of the first stroke.

10. The computer program product of claim 8, wherein the second instructions scale the stroke length parameter of the first stroke as a ratio of a reference area to the input area.

11. The computer program product of claim 8, wherein the second instructions, responsive to the first instructions determining a start point and an end point of a second stroke input into the computer interface, recalculate the input area.

12. The computer program product of claim 11, wherein the first instructions calculate a stroke length parameter of the second stroke.

13. The computer program product of claim 12, wherein the second instructions rescale the stroke length parameter of the second stroke according to the recalculated input area.

14. The computer program product of claim 11, wherein the recalculated input area bounds the first stroke and the second stroke at coordinate extrema of the first stroke and the second stroke.

15. The computer program product of claim 14, wherein the second instructions rescale the stroke length parameter of the first stroke according to the recalculated input area.

16. A data processing system comprising:

a pointing device for receiving a first handwritten character stroke;

a memory that contains a set of instructions; and

a processing unit, responsive to execution of the set of instructions, for determining a start point and an end point of the first handwritten character stroke and calculating a stroke length parameter from the start point and the end point and, responsive to determining the start point and the end point, for calculating an input area into which the first handwritten character stroke was supplied, wherein the calculated stroke length parameter is scaled according to the calculated input area.

17. The data processing system of claim 16, wherein the calculated input area bounds the first handwritten character stroke at coordinate extrema of the first handwritten character stroke.

18. The data processing system of claim 16, wherein the processing unit, responsive to determining a start point and an end point of a second handwritten character stroke, recalculates the input area, wherein the recalculated input area bounds the first handwritten stroke and the second handwritten stroke at coordinate extrema of the first handwritten character stroke and the second handwritten character stroke.

19. The data processing system of claim 18, wherein the processing unit, responsive to recalculating the input area, rescales the stroke length parameter.

20. The data processing system of claim 18, wherein the processing unit, responsive to determining the start point and the end point of the second handwritten character stroke, calculates a stroke length parameter of the second handwritten character stroke and scales the stroke length parameter of the second handwritten character stroke in relation to the recalculated input area.

23. The computer program product of claim 20, wherein the first instructions display a second stroke input in the collection area, the second instructions, responsive to input of the second stroke, for recalculating the input area, scaling the second stroke according to the recalculated input area, and resealing the first stroke according to the recalculated input area.

24. The computer program product of claim 23, wherein the third instructions display the rescaled first stroke and the scaled second stroke in the window.

21. A computer program product in a computer readable medium for scaling a parameter derived from a handwritten character stroke comprising:

first instructions for displaying a collection area in a computer interface adapted to display a first stroke input into the collection area;

second instructions for calculating an input area in which the first stroke was supplied and, responsive to calculating the input area, scaling the stroke according to the input area; and

third instructions for displaying the scaled stroke in a window of the computer interface.

22. The computer program product of claim 21, wherein the window is a predefined area of the computer interface.