International Journal of Advancements in Research & Technology, Volume 2, Issue 8, August-2013 103
ISSN 2278-7763
Copyright © 2013 SciResPub. IJOART
Relational Features of Remote Sensing Image Classification
using Effective K-Means Clustering
T. Balaji
1
, M. Sumathi
2
1
Assistant Professor, Dept. of Computer Science, Govt. Arts College, Melur, India
2
Associate Professor, Dept. of Computer Science, Sri Meenakshi Govt. College for Women, Madurai, India
1
bkmd_gacm@rediffmail.com,
2
sumathivasagam@gmail.com
ABSTRACT
The feature based classification of remotely sensed
image is used to assign corresponding levels with respect
to groups with homogeneous characteristics, with the aim
of discriminating multiple objects from each other within
the image. Every level of an image is called class. This
will be executed on the basis of spectral or spectrally
defined features such as density, texture and many other
things in the feature space. This paper focuses remote
sensing image classification of color feature based using
k-means clustering method. K-means is one of the
simplest unsupervised learning algorithms that solve the
well-known clustering problem. The procedure follows a
simple and easy way to classify a given data set through a
certain number of clusters. The main idea is to define k
centroids, one for each cluster. These centroids should be
placed in a cunning way because of different location
causes different result. So, the better choice is to place
them as much as possible far away from each other. The
next step is to take each point belonging to a given data
set and associate it to the nearest centroid. When no point
is pending, the first step is completed and we need to re-
calculate k new centroids of the clusters resulting from
the previous step. After we have these k new centroids, a
new binding has to be done between the same data set
points and the nearest new centroid. A loop has been
generated. As a result of this loop we may notice that the
k centroids change their location step by step until no
more changes are done. Here we introduce several widely
used algorithms that consolidate data by clustering or
grouping and then present a suitable method is remote
sense application based k-means cluster algorithm. It is
possible to reduce the computational cost and gives a
high discriminative power of regions present in the
image.
Keywords: Classification, Clustering, Unsupervised,
Segmentation and Partitioning
1 INTRODUCTION
Remote sensing image classification refers to the task
of extracting information classes from a multiband raster
image. The resulting raster from image classification can
be used to create thematic maps. Depending on the
interaction between the analyst and the computer during
classification, there are two types of classification:
supervised and unsupervised. The objective of image
classification is to identify and portray, as a unique gray
level (or color), the features occurring in an image in
terms of the object or type of land cover these features
actually represent on the ground. A broad group of
digital image processing techniques of remote sensing
application explains the image classification techniques
are most generally applied to the spectral data of a single-
date image or to the varying spectral data of a series of
multidimensional images. Clustering involves a set of
point into non-overlapping groups or points; where
points in a cluster are more similar to one another than
points in other clusters. The term more similar, when
applied to clustered points, usually means closer by some
measure of proximity. When a dataset is clustered, every
point is assigned to some cluster and every cluster can be
characterized by a single reference point, usually take an
average of the points in the cluster. Any particular
division of all points in a dataset into clusters is called a
partitioning. Clustered data require considerably less
storage space and can be manipulated more quickly than
the original data. The value of particular clustering
method will depend on how relatively the reference
points represent the data as well as how fast the program
runs.
A general classification procedure of remotely sensed
image is shown in the following fig. 1.
Fig. 1. General Procedure for Classification
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