Unambiguous alphabet for data compression
US5031215A · kind A · utility
Inventor
Key dates
| Filing date | May 29, 1990 |
| Grant date | Jul 9, 1991 |
| Priority date | — |
| Expiry date | May 29, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V30/10
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An item bearing an indicia which verifies a status of the item and a method and apparatus for applying such indicia. The indicia represents an encrypted message and has the form of a number n base N number system represented by characters selected from an unambiguous machine-readable character set having n characters. The characters consist of connected graphs drawn on a predetermined grid and meeting certain selected requirements. A set of descripters is selected, including a number of type 1 and type 3 points in a character and a subset of characters is selected from the set of all possible characters meeting the requirements so that each character is unambiguously described in terms of the selected descripters. In one embodiment disclosed the item is a mail piece and the status is the payment of postage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.