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Comprehensive
Meaning Of Segmentation By Clustering |
by:
Eng.Mohamed
S. El Kayyali |
Segmentation
as a word, means to classify the objects
that are exists in an image, it has many
theories and methodologies, assume that
we would like to recognize objects in an
image, there are too many pixels to handle
each individually, instead, we should like
some form of compact, summary representation.
Although, superficially these different
methods may seem some how complicated for
any reader, in this article I will demonstrate
the meaning of clustering in segmentation.
One natural view of segmentation is that
we are attempting to determine which components
of data set naturally belong together. This
is a problem known as clustering.
We can cluster in two ways:
-Partitioning: here we have a large data
set, and curve it up according to notion
of the association between items inside
the set. We would like to decompose it into
pieces that are good according to our model.
For example we can decompose an image into
regions that have coherent color and texture.
-Grouping: in this part we have distinct
data items, and we would like to collect
sets of data items that make sense together.
The key here is to determine what representation
is suitable for the problem at hand, we
need to know by what criteria a segmentation
method should decide which pixels belong
together and which do not.
Once we decide which cluster method suitable
for our application, segmentation by clustering
could be very useful for some applications
that may use clustering, as well as summarizing
video, or finding machine parts, finding
people in mage, finding buildings in satellite
images: these done by looking for collections
of edge points that can be assembled in
line segment and then assembling line into
polygons.
It is hard to see that there could be a
comprehensive theory of segmentation, not
least what is interesting and what is not
depends on the application, there is no
comprehensive theory of segmentation at
time of writing.
Since clustering is defined above, in addition
clustering is a process whereby a data set
is replaced by cluster, it is natural to
think of segmentation as clustering, another
meaning: pixels may belong together because
they have the same color, the same texture,
they are nearby, and so on. Some of clustering
methods as well as: clustering by K-means,
segmentation by graph theoretic clustering.
About the author:
M.sc Eng. Mohamed S. El Kayyali - Resercher
engineer at USMP and UTP medical image processing,
founder of Kayyali edge detection theory.
IEEE and CIPPRS member
Circulated by Bandoni
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