Extraction of water-body in remote sensing image based on logic operation

In this paper, we put forward an approach to extract water-body in remote sensing image using logic operation defined by ourselves. In order to use this method to extract water-body, firstly, NDVI was calculated from multi-spectral image, and vegetation was removed by a certain threshold; Secondly, artificial buildings, cultivated land, cloud, and bare land were extracted according to the spectral signature among different bands of various objects; Finally, water-body was accurately labeled by the logic operation between images of water-body and other objects. The experiment on a LANDSAT TM imagery of the District of Poyang Lake, China´s largest freshwater lake, including different types of water-bodies was carried out and the result indicated that it could effectively distinguish water-body pixels from non-water-body pixels, and it also could effectively exclude the negative influence of shadow of thin cloud. The experiment obtained high accuracy for the extraction of water-body in TM imagery.