Extraction And Application Of Building And Shadow Of ZY3 Image Based On Improving Morphological Index

With the rapid development of remote sensing technology, it’s possible to provide better service for urban construction and management by using remote sensing to obtain information of city buildings. At the same time, the increasing complexity of the image interpretation also brings new challenges. In particular, high-resolution remote sensing images are affected by all kinds of noises while providing feature distribution information and fine spatial structure. The application of remote sensing images which can not realize accurate and automated interpretation has been restricted in various aspects.In the remote sensing images, the shadows are removed as a kind of noise, but the shadows can provide three-dimensional information of the buildings. According to the geometric relationship between the height of buildings and the length of shadows, the height of buildings can be estimated by using the length of shadows. This method is more convenient to obtain the height of buildings compared to the other methods, and can be used in large areas.In this paper, buildings are extracted by the method of improving the morphological index, and the height of buildings are estimated based on the length of shadows. The effectiveness of this method has been analyzed by experimenting. Finally the method has been applied to BeiLin Xi’an. The main research work includes the following aspects.(1)It has introduced a basic operation of mathematical morphology and its advantages in processing remote sensing images.(2)It has introduced the existing methods of extraction algorithm of buildings and shadows. Buildings are extracted by improved morphological structure index,and noises are removed by the use of buildings’ spatial features after extraction.Buildings are extracted by using morphological shadow index,and compared this method with traditional threshold segmentation based on histogram.(3) According to the geometric relationship between the height of buildings and the length of shadows, it has discussed estimation method of the height of buildings based on shadows, and ultimately has achieved the purpose of classification of the height of buildings.(4) The above method has been applied to obtain and analyze distribution, height grade of buildings in Bei Lin.