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EVALUATION OF THE EFFECTIVENESS OF VARIOUS ENHANCEMENT
AND IMAGE MANIPULATION TECHNIQUES *
by
N.K. Vyas*
and
D.S. Kamat*
ABSTRACT
Various kinds of image enhancement and manipulation
techniques are available which, in general try to improve
the image interpretability. However, there is no standard
method that can tell as to which technique is best suited
to bring out particular features in a particular image,
with optimum clarity.
This is partly because each image has its own unique
Spatial distribution of intensity or brightness and partly
because there is no quantitatives measurement available
which can tell the effectiveness of an enhancement procedure
in a particular situation.
In this paper, the contrast of features and the homoge-
neity of textures are taken as of fundamental importance to
thé interpretation process and an analysis is made as to how
the gray level co-occurence matrix will be influenced by any
image manipulation procedure. The contrast and the homogeneity
for both the original and the modified matrices are calculated
and represented in two dimensional feature space having the
homogeneity as one axis and the contrast as the other,
- ED ED cnp GD GD an ED ED SID u D D ED DE ED DD ED DEE ED DD ED ED ED DC ED ED ED ED SD HE aD OD AD DD U xD eue US CUP = GD = WD nm ce cm
Space Applications Centre, (ISRO) Ahmedabad-380053 INDIA
+ Paper to be grosentsd at ISPRS Commission VII Symposium
to be held at Toulouse (France) during 13-17th Sep.,1982
in the session on Methodology for Enhancement.
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