METODOLOGIA AUTOMÁTICA PARA EXTRAÇÃO DE CRUZAMENTO DE RODOVIAS EM IMAGENS DE ALTA RESOLUÇÃO

Researches on road extraction from digital images are not recent, being the first one from 70's. The methods developed are usually classified into two classes, i.e., semi-automatic and automatic. Concerning this last class, no intervention with the operator is expected. In this context, the road crossing extraction is fundamental, although very few works are found in the relevant literature. The main reason is the great diversity of road crossings, bringing some difficulties to build up a priori knowledge of them. This research proposes a methodology for solving this problem combining road segments extracted from a high - resolution image (pixel < 0.7 m), with lines extracted from a low - resolution image (pixel > 2m) resampled from the original, high - resolution image. The proposed methodology was tested with a set of high - resolution image, showing that it is reliable and efficient. Whenever the road edges were well - defined the method was able to totally extract the road crossings. In addition it provided road networks with completion significantly better (about 20%) than the corresponding ones previously extracted by the automatic road segment extraction method.