Fast transform based offset determination
US9268025B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 2012 |
| Grant date | Feb 23, 2016 |
| Priority date | — |
| Expiry date | May 12, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An offset estimator (e.g., a time delay, a spatial image offset, etc.) makes use of a transform approach (e.g., using Fast Fourier Transforms). The sparse nature of a cross-correlation is exploited by limiting the computation required in either or both of the forward and inverse transforms. For example, only a subset of the transform values (e.g., a regular subsampling of the values) is used. In some examples, an inverse transform yields a time aliased version of the cross-correlation. Further processing then identifies the most likely offset of the original signals by considering offsets that are consistent with the aliased output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.