Automatic handwriting recognition using both static and dynamic parameters
US5550931A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 1995 |
| Grant date | Aug 27, 1996 |
| Priority date | — |
| Expiry date | May 25, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V30/347
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Methods and apparatus are disclosed for recognizing handwritten characters in response to an input signal from a handwriting transducer. A feature extraction and reduction procedure is disclosed that relies on static or shape information, wherein the temporal order in which points are captured by an electronic tablet may be disregarded. A method of the invention generates and processes the tablet data with three independent sets of feature vectors which encode the shape information of the input character information. These feature vectors include horizontal (x-axis) and vertical (y-axis) slices of a bit-mapped image of the input character data, and an additional feature vector to encode an absolute y-axis displacement from a baseline of the bit-mapped image. It is shown that the recognition errors that result from the spatial or static processing are quite different from those resulting from temporal or dynamic processing. Furthermore, it is shown that these differences complement one another. As a result, a combination of these two sources of feature vector information provides a substantial reduction in an overall recognition error rate. Methods to combine probability scores from…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.