Fire Detection Algorithms Using Multimodal ... - Bilkent University

ABSTRACTFIRE DETECTION ALGORITHMS USINGMULTIMODAL SIGNAL AND IMAGE ANALYSISBehçet Uğur TöreyinPh.D. in Electrical and Electronics EngineeringSupervisor: Prof. Dr. A. Enis ÇetinJanuary, 2009Dynamic textures are common in natural scenes. Examples of dynamic texturesin video include fire, smoke, clouds, volatile organic compound (VOC)plumes in infra-red (IR) videos, trees in the wind, sea and ocean waves, etc.Researchers extensively studied 2-D textures and related problems in the fieldsof image processing and computer vision. On the other hand, there is very littleresearch on dynamic texture detection in video. In this dissertation, signal andimage processing methods developed for detection of a specific set of dynamictextures are presented.Signal and image processing methods are developed for the detection of flamesand smoke in open and large spaces with a range of up to 30m to the camerain visible-range (IR) video. Smoke is semi-transparent at the early stages of fire.Edges present in image frames with smoke start loosing their sharpness and thisleads to an energy decrease in the high-band frequency content of the image.Local extrema in the wavelet domain correspond to the edges in an image. Thedecrease in the energy content of these edges is an important indicator of smokein the viewing range of the camera. Image regions containing flames appear asfire-colored (bright) moving regions in (IR) video. In addition to motion andcolor (brightness) clues, the flame flicker process is also detected by using a HiddenMarkov Model (HMM) describing the temporal behavior. Image frames arealso analyzed spatially. Boundaries of flames are represented in wavelet domain.High frequency nature of the boundaries of fire regions is also used as a clue tomodel the flame flicker. Temporal and spatial clues extracted from the video arecombined to reach a final decision.iv