Remote Sensing and GIS Application Lecturer Ruba Yousif
Remote Sensing and GIS Application Lecturer Ruba Yousif Hussain Third Year 1
Remote Sensing and GIS Application Third Year Lecturer Ruba Yousif Hussain Image classification is the process of sorting pixels into a finite number of individual classes, or categories, of data based on their pixel values. If a pixel satisfies a certain set of criteria, then the pixel is assigned to the class that corresponds to that criterion. There are two ways to classify pixels into different categories: 1. Unsupervised Classification Unsupervised classification is a method of identifying grouping and labeling features in an image according to their spectral values. Arc. GIS performs Iso Cluster unsupervised classification 2. Supervised Classification In supervised Classification , the user relies on her/his own pattern recognition skills and a priori knowledge of the area to help the system determine the statistical criteria ( signatures ) for data classification. Arc. GIS provides four supervised classification options: 1. Interactive 2. Maximum Likelihood 3. Class Probability 4. Principal Components 2
Remote Sensing and GIS Application Third Year Lecturer Ruba Yousif Hussain Laboratory Unsupervised Image Classification Purpose Identification of grouping and labeling features in an image according to their spectral values. Application and Data Arc. GIS Satellite Image Tutorial Urban / built up = 1 , red Agriculture = 2 , green Water = 3 , blue Transportation = 4 , gray Open a new map document enable Spatial Analysis Extension 3
Remote Sensing and GIS Application Third Year Lecturer Ruba Yousif Hussain add image classification toolbar add image left click on the down arrow next to classification and it gives you list of classification methods left click on Iso Cluster Unsupervised classification 4
Remote Sensing and GIS Application Third Year Lecturer Ruba Yousif Hussain Click Ok Arc. Map will automatically add your new file to the Table of Contents and map document window. 5
Remote Sensing and GIS Application Third Year Lecturer Ruba Yousif Hussain Change the color for any spectral class that has the following classes Urban / built up = 1 , red Agriculture = 2 , green Water = 3 , blue Transportation = 4 , gray 6
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