Perceptual grouping of regular structures for automatic detection of man-made objects

Human observers perceive man-made objects in images from the visual spectrum domain as well as in IR or SAR imagery. Mechanisms like perceptual grouping are crucial to this capability. In this paper two examples for grouping in different image sources are discussed. The first example is activity estimation in urban areas from thermal IR images. The grouping of vehicles into rows is performed along the margins of the roads. The other example is related to the detection of industrial buildings from InSAR data. Such buildings often show salient regular patterns of strong scatterers on their roofs. A previous segmentation which uses the intensity, height and coherence information extracts building cues. Strong scatterers are filtered by a spot detector and localized by a cluster formation. These scatterers are grouped in rows by a process that uses the contours of the building cues as context.