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ing areas for. the multispectral analysis will be detected
automatically, without a priori knowledge. Here the complementary
properties of a contrast extraction algorithm and a region growing
algorithm are exploited...
For the texture analysis we can distinguish between the
statistical and the structural texture analysis. The main
properties of these methods are.discussed here. Investigations
about the statistical texture analysis show that an essential
problem of the statistical texture analysis is the dependence
of the extracted features from the size and shape of the defined
raster elements. It will be demonstrated that the shortcomming
of the statistical texture analysis methods can be decreased by
an additional combination with the structural texture analysis.
Based on the results of the investigations a complex processing
system exploiting the different types of properties and combining
the complementary methods will be proposed. ;
COMPARISON OF MULTISPECTRAL AND TEXTURAL METHODS
With regard to the combination of the multispectral and textur
analysis, their principal properties will be compared first.
Investigations /1, 2, 5, 6/ demonstrate the characteristic pro-
perties of the different methods:
- a) multispectral analysis:
- Complete classification with high resolution of spectral
homogeneous objects
- Additional classification of line shaped objects and point
like objects
- Bad classification of textured areas with a large part
of reject
- b) statistical texture analysis:
- À better detection of objects with essentially textural
features
- A simultaneous detection of spectral homogeneous objects
- A gmall resolution on object boundaries
- No detection of line shaped and point like objects.
- c) structural texture analysis:
- Detection of line shaped and point like objects too
- High resolution of detecting region boundaries
- Difficult detection of spatial relationships with dominant
statistical nature
- High expense
The aim is a cumulation of the advantages of the different
methods. This may be realized by a spatial selective use of the
different methods dependent upon the kind of objects to be pro-
cessed. This assumes the knowledge about the spatial probability
distribution of objects in the image. Without a priori knowledge,
this information have to be extracted step by step with a suitable
sequence of different segmentation methods.
36
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