Maskable bilevel correlators
US5020113A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1988 |
| Grant date | May 28, 1991 |
| Priority date | — |
| Expiry date | Aug 8, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/51
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for correlating two signals representing a live image and a reference image are disclosed. The reference signal is processed to provide a polarity bit and mask bit for each pixel position in the reference image. The processed video signal is stored in a memory 20 and used in a convolver and summer section 18 in which the polarity bits between the reference and live images are gated by gate 17 and are used in generating a correlation output from summer 23. However, the polarity bits do not affect the correlation output if the logical output from gate 19 is of a given state which occurs if the associated mask bits indicate that the gradient value at the particular pixel position does not exceed certain minimum threshold values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.