Image emphasizing device for fingerprint verification
US6718052B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 2000 |
| Grant date | Apr 6, 2004 |
| Priority date | — |
| Expiry date | Mar 9, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20192
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A minute amplitude value emphasis device 2 has Fourier transformation devices 211, 212 which treat a two-dimensional original pictorial image 200 with a Fourier transformation to determine Fourier coefficients in x-axis and y-axis directions. Weight devices 221, 222 emphasize the respective Fourier coefficients in the corresponding directions so as to produce weighted Fourier coefficients. Inverse Fourier transformation devices 231, 232 treat the weighted Fourier coefficients with an inverse Fourier transformation in two directions to determine the corresponding minute amplitude value emphasis data 241, 242. A synthesizing device 250 synthesizes the corresponding minute amplitude value emphasis data 241, 242 to produce a minute amplitude value emphasis image 260. An obscure portion of the two-dimensional original pictorial image 200 is rectified to reproduce a clarified pictorial image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.