document: Extracting straight road structure in urban environments using IKONOS satellite imagery We discuss a fully automatic technique for extracting roads in urban environments . The method has its bases in a vegetation mask derived from multispectral IKONOS data and in texture derived from panchromatic IKONOS data . These two techniques together are used to distinguish road pixels . We then move from individual pixels to an object-based representation that allows reasoning on a higher level . Recognition of individual segments and intersections and the relationships among them are used to determine underlying road structure and to then logically hypothesize the existence of additional road network components . We show results on an image of San Diego , California . The object-based processing component may be adapted to utilize other basis techniques as well , and could be used to build a road network in any scene having a straight-line structured topology
doc_bio_tags: O B I I O B I O B I I O O O B I I O O O O B I O O O O O O O O B I O O O O O O O B O O B I I O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
extractive_keyphrases: straight road structure urban environments ikonos satellite imagery fully automatic technique vegetation mask texture panchromatic ikonos data road pixels road network components san diego
abstractive_keyphrases: object-based representation higher level reasoning individual segment recognition object-based processing component straight-line structured topology high-resolution imagery large-scale feature extraction vectorized road network