Signal processing for autonomous acquisition of objects in cluttered background
US4937878A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1988 |
| Grant date | Jun 26, 1990 |
| Priority date | — |
| Expiry date | Aug 8, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T7/254
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are disclosed for detecting moving objects silhouetted against background clutter. A correlation subsystem 12 is used to register the background of a current image frame (framestore 1) with an image frame taken two time periods earlier (framestore 3). A first difference image is generated by subtracting the registered images, with the first difference image being filtered by low pass filter 34 and thresholded by a three level segmenter 36. A second difference image is likewise generated between the current image frame and another image frame taken at a different subsequent time period. This second difference image is likewise filtered and thresholded. The two difference images are logically ANDed together by gate 39 whose output is connected to a formatter, sorter and feature extractor 40. Track files are generated in CPU 16 for comparing subsequently extracted image features with previously stored extracted features.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.