Patent · US Expired

Monitoring system using infrared image processing

US4999614A · kind A · utility

42Cited by
6References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 28, 1988
Grant dateMar 12, 1991
Priority date
Expiry dateNov 28, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B13/194
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Temperature data of each picture element output from a infrared camera looking at a scene to be watched is compared with the same data of a previous frame. Temperature data which has changed from the previous frame is input to a histogram operator having a region defined by the temperature change and quantity of the picture elements. When the quantity of picture elements in the defined region exceeds a threshold level, it is recognized that a certain object having considerable temperature change and size has been detected. Thus, a signal is output to trigger an alarm system, or to sustain circulating frame memories which have recorded the previous scenes so that the scenes of visible light as well as the temperatue patterns for frames before, on, and after the trigger signal can be reproduced as visual images of a display screen.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.