Study On Remote Sensing Extraction Of Yellow River Water Based On GF-5 High Spectral Data

The Yellow River is named for the high sediment content,because the existence of sediment makes the Yellow River water spectral characteristics have special,the Yellow River from upstream to downstream,sediment content is different,using the same method,will make the extraction results different,and GF-5 high spectral data has many bands,narrow spectral range,can continuously obtain the spectral information of land,through the Yellow River to identify different spectral reflectivity.Therefore,in order to solve the above problems,this paper also provides a basis for the water situation monitoring of the Yellow River.Taking the GF-5 AHSI hyperspectral data as the data source,different types of Yellow River water bodies are extracted through the Yellow River water index method and the classification of different turbidity water bodies.The water index band of the Yellow River is determined by the image quality evaluation and band availability analysis,and the turbidity model has been established to provide support for the classification and turbidity analysis of different types of water bodies in the Yellow River,and finally realize the extraction of the Yellow River water bodies.The main research work in this paper includes the following four parts:(1)GF-5 AHSI hyperspectral data quality evaluation and availability analysis of the band.For many GF-5 hyperspectra data bands,the GF-5 AHSI hyspectral data was quality evaluated and availability analyzed by three indicators of noise standard difference,information entropy and clarity.(2)Relative turbidity model of the Yellow River water body.Because the physical model method in turbidity modeling does not need the advantages of synchronous measured data,this paper,this method is selected to establish the turbidity model,that is,using the relationship between the spectral reflectivity characteristics of the Yellow River water band and the turbidity,to establish the relative turbidity model of the two-band method.(3)Optimization of Yellow River water index threshold and Yellow River water extraction.The selection of water index threshold directly affects the extraction accuracy by using the histogram method and using the ROC curve.The spectral characteristics of different turbidity water bodies are defined by different types of water,true color display of image and turbidity value of different turbidity.Then,8 Yellow River water index methods are used to extract different turbidity water bodies,and compare the extraction accuracy of 8 methods in different types of water bodies,the most applicable method for each type is obtained.(4)Relative turbidity condition.In order to obtain the turbidity of the Yellow River,the turbidity of the upper,middle and lower reaches of the Yellow River.This paper has 21 pictures,15 tables and 85 references.