Digital focusing method and apparatus in image processing system
US6154574A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 1998 |
| Grant date | Nov 28, 2000 |
| Priority date | — |
| Expiry date | Aug 28, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20056
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Digital focusing method and apparatus in an image processing system, for digitally focusing an out-of-focus image, are provided. A defocused image is divided into sub-images of a predetermined size. An edge direction of each of the divided sub-images is estimated. Step responses with respect to the respective edge directions are calculated. A mean step response is obtained by averaging a predetermined number of the step responses. Point Spread Function (PSF) coefficients are obtained using the mean step response. An image blur transfer function is obtained using the PSF coefficients. An image restoration transfer function is obtained using the image blur transfer function. An original in-focused image is obtained by multiplying the image restoration transfer function by the defocused image in a frequency domain. Thus, an image can be restored in real time, and the size and weight of the image processing system can be reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.