Skip to main content

K-means clustering in Remote Sensing

K-means clustering is a method of unsupervised machine learning used to classify data into k clusters based on their similarity. In remote sensing, it is often used to classify satellite or aerial imagery based on the spectral characteristics of each pixel.


Here's an example of how K-means clustering might be used in remote sensing:


A satellite captures an image of a region, and the data is collected for each pixel in the image.


Each pixel in the image has several spectral bands, such as red, green, and blue.


The K-means algorithm is used to classify each pixel in the image based on the values of these spectral bands.


The algorithm starts by randomly selecting k centroids (representative points) within the data set.


Then, it assigns each pixel to the closest centroid based on the distance between the pixel's values and the centroid's values.


The algorithm then calculates the mean of all the pixels in each cluster, and uses these means as the new centroids.


This process is repeated until the clusters no longer change.


The resulting image is a classification map, where each pixel is assigned to one of k clusters, or classes, based on its spectral characteristics.


In remote sensing, the resulting image is usually a color composite image, where each class is assigned a unique color.





Comments

Popular posts from this blog

Kuhn’s Paradigms

The given content explains Thomas S. Kuhn’s model of scientific development , its application to geography, and criticisms by Karl Popper, Paul Feyerabend, Michel Foucault , and others. 1. Basic Idea Kuhn argued that science does not develop continuously in a straight line . Instead, scientific development occurs through: Preparadigm → Paradigm → Normal Science → Crisis → Scientific Revolution → New Paradigm A new paradigm may replace an older one, producing a major change in the way scientists understand and study a subject. Concepts and Terminologies Concept / Term Simple Meaning Paradigm A commonly accepted framework/model that guides scientific research Exemplar A successful concrete problem-solution used as a model for future research Disciplinary Matrix Shared beliefs, values, concepts, methods and techniques of a scientific community Preparadig...

History of Geography.

Chronological sequence and categorized by era and region. I. Introduction & Etymology •  Etymology : The term "Geography" derives from the Greek γεωγραφία (geographia) , meaning "Earth-writing" (description or writing about the Earth). •  First Use : Eratosthenes (276–194 BC) was the first person to use the word. •  Pre-Term Practices : Recognizable geographic practices like cartography (map-making) existed prior to the coining of the term. II. Antiquity & Ancient Civilizations 1. Ancient Egypt (Pre-Classical) •  Cosmology : Ancient Egyptians viewed the Nile as the center of the world, with existence based upon "the" river. •  Geographical Knowledge : •  Oases : Known to the east and west, considered locations of various gods (e.g., Siwa for the god Amon ). •  Kushitic Region : Lay to the south, known as far as the 4th cataract . •  Punt : A region located south a...

Models and Theories in Geography

Geographical Models A model is a simplified representation of reality used to describe, explain, simulate, and predict geographical phenomena. Types Physical (Iconic) Models – Three-dimensional representations (e.g., globe, relief model). Conceptual Models – Diagrams or frameworks explaining geographical relationships. Mathematical (Quantitative) Models – Equations and statistical models for spatial analysis and prediction. Simulation Models – Computer-based models that simulate geographical processes (e.g., climate, flood, urban growth). Major Geographical Models Model Scholar Year Concept Johann Heinrich von Thünen Agricultural Land Use Model 1826 Land use varies with distance from the market. Walter Christaller Central Place Model 1933 Distribution of settlements and services. Ernest Burgess Concentric Zone M...

Building Topology in GIS, Data Query in GIS, Geoprocessing and Automation in GIS

A Geographic Information System (GIS) is more than a digital mapping tool. It is a comprehensive system for capturing, storing, managing, analysing, querying, and visualising spatial (geographic) and non-spatial (attribute) data . To maintain accurate spatial data and perform advanced analyses, GIS relies on three important concepts: Building Topology Data Query Geoprocessing and Automation These concepts ensure data integrity, efficient data retrieval, and automated spatial analysis , making GIS an indispensable tool in geography, environmental science, urban planning, disaster management, transportation, agriculture, and resource management. 1. Building Topology in GIS Topology is the mathematical and logical framework that defines the spatial relationships between geographic features such as points, lines, and polygons. It ensures that spatial data maintain correct geometric relationships even after editing or analysis. Simple Definiti...

Regional Geography, Systematic Geography, Idiographic, Nomothetic, Inductive and Deductive Approaches

T wo major ways of studying Geography : the Regional Approach and the Systematic Approach . It also explains the related ideas of idiographic vs. nomothetic and inductive vs. deductive reasoning , especially in the context of the Hartshorne–Schaefer debate . 1. Regional Geography: “All About One” Regional Geography studies one particular region in detail . A region is an area that has some degree of homogeneity (sameness) within its boundary but is also unique or different from other regions . For example, if we study Palakkad District , we may study: Relief and drainage Climate Soil Vegetation Agriculture Population Occupation Economy Culture Political characteristics The purpose is to understand the complete geographical personality of Palakkad and the relationships among its different features. Key concepts Region: A geographical area with identifiable characteristics and boundaries. Homogeneity: Si...