Handprinted symbol recognition system
US4491960A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 5, 1982 |
| Grant date | Jan 1, 1985 |
| Priority date | — |
| Expiry date | Apr 5, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/40
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A handprinted symbol recognition system for identifying through computer techniques free-form, unconstrained handprinting in which accuracy is decoupled from efficiency converts a thin-line (skeletonized) figure output from a preprocessing system, in the form of an array of "black" image points from a raster line sampling, into segment-oriented lists. The segment-oriented lists are filtered and data compressed to obtain a reduced more suitable subset of points approximating the symbol for further processing. The topologic features of the image are extracted from the subset. Short segments that are potential spurs are removed, the image is rotated as necessary and normalized as to size. Each segment and their interrelationships are analyzed to extract geometric features for use in conjunction with the topologic features in a logic tree decision mechanism which uses three modules: (1) pre-recognition ("trash" filter), (2) potential symbol identification, and (3) final quality assurance. The pre-recognition module separates all possible non-meaningful images from those the recognition system has a chance of identifying with minimal misclassification. The symbol identification module u…
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