Pattern extraction apparatus
US6195460A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Apr 30, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/431
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Collation Fourier image data (FIG. 1D) FB generated by performing the two-dimensional discrete Fourier transform (DFT) for the image data (FIG. 1C) of a collation pattern is synthesized with registration Fourier image data (FIG. 1B) generated by performing the two-dimensional DFT for the image data of a registration pattern. After amplitude suppression processing is performed for the resultant data, two-dimensional DFT is performed. A correlation peak is extracted from a correlation component area which appears in the synthesized Fourier image data (FIG. 1E) for which the two-dimensional DFT has been performed. A predetermined area including this correlation peak is then masked (FIG. 1F). The two-dimensional DFT is performed for the masked synthesized Fourier image data, and amplitude restoration processing is performed for the data. The resultant data is re-synthesized with the registration Fourier image data FA, and the two-dimensional IDFT is performed for the synthesized data. With this processing, image data containing a difference pattern like the one shown in FIG. 1G or a moving pattern can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.