Smoothed local histogram filters for computer graphics
US8406518B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2009 |
| Grant date | Mar 26, 2013 |
| Priority date | — |
| Expiry date | Jan 25, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20028
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Local histogram and local histogram-based functions can be determined by generating offset-kernel images based on domain-shifted tonal filter kernels. The offset-kernel images can be reused for multiple image locations and/or local neighborhood sizes, shapes, and weights. A neighborhood filter representing the desired local neighborhood size, shape, and frequency domain characteristics is applied to each of the offset-kernel images. Neighborhood filters may include a temporal dimension for evaluating neighborhoods in space and time. Neighborhood filtered offset-kernel images' values represent samples of local histogram or local histogram-based function corresponding with the domains of their associated domain-shifted tonal filter kernels. Arbitrary functions may be used as tonal filter kernels. A histogram kernel may be used to sample values of local histogram functions. A tonal filter kernel that is a derivative or integral of another tonal filter kernel may be used to sample a derivative or integral, respectively, of a function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.