Patent ID: 6184792
Filing Date: 2001-02-06
Classification: F23N,G08B

Abstract:
A method of detecting fire in a monitored area, said method comprising the steps of:detecting and capturing, at a prescribed frequency, video images of said monitored area in the form of two-dimensional bitmaps whose spatial resolution is determined by the number of pixels comprising said bitmaps,cyclically accumulating a sequential set of said captured bitmaps for analysis of the temporal variations in the brightness values observed at each of said pixels, said temporal variations being expressible in terms of a static and a dynamic component of said variations in pixel brightness values,examining said set of bitmaps to identify a static cluster of contiguous pixels having a static component of said brightness values that exceed a prescribed static threshold magnitude,examining said set of bitmaps to identify a dynamic cluster of contiguous pixels having a dynamic component of said brightness values that exceed a prescribed dynamic threshold magnitude, andcomparing the patterns of the shapes of said identified, static and dynamic clusters to identify those exhibiting patterns which match to a predetermined matching level those exhibited by the comparable static and dynamic regions of the type of fire for which said area is being monitored.