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Quantified Adaptive Fusion of Spectral Bands
and Out-Image Data


Quantified adaptive fusion such as we modified it behaves very well when the number of sources to be merged increases. The class having the largest consensus is always selected, and this system shows its efficiency when new sources are added. Generally, adding information leads to an improvement of classification.

For conjunctive fusion, the addition of out-image data to spectral bands leads to a great increase of the number of unclassified pixels. In effect, it is quite impossible to obtain the unanimity of the sources on the assignment of a pixel to a class.

On the other hand, quantified adaptive fusion manages the additional sources very well. The areas of classification obtained for each class are very homogeneous. All the classes are well recognized, except for the recognized class 7 with 58.17%, and to a lesser extent of the recognized class 8 with 71.90%.

We note on this example that, when the sources are numerous but globally concordant, a majority of sources in agreement is sufficient to decide to assign a pixel to a class. This process works well because the sources of information to be merged are globally coherent. Most of the time, we do not have a very severe conflict to solve. In this case, a fusion of conjunctive type is suitable. Unanimity is not essential, and at the opposite, it locks the decision-making process since it becomes difficult to obtain the unanimity when the number of sources increases.


   


  

Table 34: Quantified adaptive fusion of the spectral bands MSS4 to MSS7 and out-image data: distance to roads, plateaux, vales, slope orientation, slope steepness, edges, irrigation, DEM and distance to urban areas.

Rates of classification obtained
$\mbox{\ }$Class Number of pixels  

correctly classified

(A)             

Number of pixels

in samples     

(B)            

Rate of pixels    

correctly classified

(A/B)         

       1 414 459 90.20%
       2 437 459 95.21%
       3 262 306 85.62%
       4 339 391 86.70%
       5 406 459 88.45%
       6 401 459 87.36%
       7 267 459 58.17%
       8 330 459 71.90%
       9 458 459 99.78%
TOTAL 3314 3910 84.76%




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