Method and apparatus for applying a filter to an image with a large range of pixel values
US7783121B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 18, 2006 |
| Grant date | Aug 24, 2010 |
| Priority date | — |
| Expiry date | Jun 21, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/20208
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
One embodiment of the present invention provides a system for applying a filter to an image whose pixel values can span a large range of values. During operation the system receives an image to which the filter is to be applied. The system then selects a first region within the image which is associated with a first pixel. Next, the system generates a first histogram using pixels within the first region whose values are within a first range of pixel values. Next, the system determines a new value for the first pixel using the first histogram. The system then selects a second region within the image which is associated with a second pixel. Next, the system determines if the second pixel value is within a second range of pixel values. If the second pixel value is within the second range of pixel values, the system determines a non-overlapping region between the first region and the second region. The system then generates a second histogram using the first histogram and pixel values in the non-overlapping region. Next, the system determines a new value for the second pixel using the second histogram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.