ion" 
n 
THE PROBLEM OF TEXTURE DEFINITION FOR IMAGE ANALYSIS 
GEOSCIENCES 
by, 
Ulrich Wieczorek. 
Institut für Geographie der 
Universität München, Abtei- 
lung Fernerkundung am Lehr- 
stuhl Prof. Gierloff-Emden 
Abstract 
By computing shape parameters of texture a more 
exact definition of image structures called "tex- 
ture" is possible. From this definition "arrange— 
ment parameters" of texture can be derived 
"7. Introduction 
A. Rosenfeld regards textures as "complex visual patterns, com- 
posed of entities or subpatterns" (A. Rosenfeld and A. Kak, 
"Digital Picture Processing",New York,San Francisco,London,1976,p.59). 
A lot of attempts are made to describe the image textures. It 
should be mentioned the remarkable ideas of R.M. Haralick and 
the investigations of the research team at the FIM in Karls- 
ruhe, Germany. One purpose of these investigations is to melio- 
rate the classification methods by supplying the spectral sig- 
natures by textural signatures. Not only automatic mapping of 
surfaces with different spectral behavior but also automatic 
mapping of different surface structures is desired. 
2. Shape Parameters of Texture 
  
For the identification of groups of objects on the earth surface 
by aid of spectral respectively textural features a correlation 
between these features and characteristical properties of the 
object groups on the earth surface has to be constructed. 
For this purpose ground checks and ground trooth measurements 
are necessary. À correlation is possible between some spectral 
properties of the objects on the earth surface and the greytone 
in the different channels of a more channel image. 
A correlation between testural features as used e.g. by Haralick 
(2.) and object properties is. not possible, because it is very 
difficult to. find measuring parameters on the earth surface which 
are equivalent to. the parameters of texture. The features defined 
by R.M. Haralick (2 ) cannot be computed for the reflection variance 
on the earth surface, because it would be necessary to. measure 
the intensity of reflexion in each point of a test site on the 
earth surface at the same time, This will be impossible. So other 
properties have to be found which cab be measured easilier on the 
earth surface. These must be properties which are interesting 
for the geoscientist.