Systems and methods for triggering an out of focus alert
US8345162B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2007 |
| Grant date | Jan 1, 2013 |
| Priority date | — |
| Expiry date | May 25, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In order to trigger an out of focus alert when the focus level of a video frame meets a focus criteria, a method is performed including the operations of: receiving a video frame, partitioning the video frame into a plurality of blocks, calculating an array of discrete cosine transformation (DCT) coefficients for at least one of the plurality of blocks using a DCT, classifying each of the at least one of the plurality of blocks based on the array of DCT coefficients for that block, calculating a focus level of the video frame from the block classifications, and triggering an out of focus alert if the focus level meets a focus criteria.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.