A method for extracting urban water bodies from satellite remote sensing images

Abstract

A method for extracting urban water bodies from satellite remote sensing images, including: preprocessing of remote sensing image data; obtaining two new normalized difference water indices NNDWI1 and NNDWI2, and obtaining water body extraction results of NNDWI1 and NNDWI2; thresholding results of NNDWI1 Superimposed with the threshold segmentation results of NNDWI2, the threshold segmentation results of NNDWI are obtained, that is, large-area water objects and small-area objects. Constrain the expanded small-area objects, and perform shadow detection and removal on the constrained small-area objects. Small-area water body objects; superimpose large-area water body objects and small-area water body objects to obtain urban water body extraction results from satellite remote sensing images. The method proposed by the invention has higher classification accuracy and lower total error rate of missed detection and false alarm, improves the subsequent water body extraction accuracy, and has higher water body edge detection accuracy.

Description

technical field [0001] The invention belongs to the technical field of water body remote sensing images, and mainly relates to a method for extracting urban water bodies from satellite remote sensing images. Background technique [0002] Cities are the embodiment of the high development of human society. As an important factor in urban ecosystems, urban water bodies play a very important role in maintaining the stability of urban ecosystems. Changes in urban water bodies will have huge changes in life, and may cause some disasters, such as urban water retention, water shortages, and even some diseases related to human health and life. Therefore, understanding and mastering the distribution of urban water bodies and the change of water area has become the focus of people's increasing attention. [0003] In recent years, with the application and development of remote sensing technology, remote sensing images have played an increasingly important role in natural resource inves...

AI Technical Summary

Problems solved by technology

If the combination of high-resolution remote sensing image shadow detection method (morphological shadow index, MSI) and NDWI is used to extract water bodies from WorldView-2 high-resolution images, in order to improve the accuracy of water body detection; although the principle of this method is simple, due to This method uses the NDWI method as the basis for water body extraction, and its detection accuracy is not very high, especially in the small area of ​​water with dense vegetation around, the spectral characteristics of the water body will be seriously polluted, and the spectral characteristics of the water body are extremely unstable. The water body has the characteristics of high suspended sediment content, serious eutrophication of the water body, and high pollution by various pollutants, which makes the optical characteristics of the urban water body and the unpolluted water body in nature different.

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