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Fusion of Spectral Bands MSS4 to MSS7
and Out-Image Data
using Bayes' Rule



Bayes' rule benefits from the additional information to make a decision on the classification of a pixel. However, it has a very severe behaviour as shown by the large number of not classified pixels (93.03%) (table "Rate of classification").

In a severe behaviour, unanimity is sought in order to make a decision. If only one source does not agree with the others, decision becomes impossible, and classification fails. That explains the very high rate of not classified pixels.

On the other hand, when unanimity is reached, it is almost sure that the good class has been found for the pixel. That is shown on the image by the localization of the classified pixels which are exclusively around the samples areas. The unanimity reinforces the reliability of the decision.


 

Figure 19: Bayes' fusion of spectral bands MSS4 to MSS7 and out-image data distance to road, plateau, valleys, slope orientation, slope steepness, crests, irrigation, DEM and distance to urban areas.


 

Rate of classification
   Class Number of pixels   

 correctly classified   

 (A)                

Number of pixels

in samples     

(B)            

Rate of pixels      

correctly classified

(A/B)            

       1 63 459 13.73%
       2 88 459 19.17%
       3 80 306 26.14%
       4 44 391 11.25%
       5 100 459 21.79%
       6 185 459 40.31%
       7 62 459 13.51%
       8 37 459 8.06%
       9 237 459 51.63%
TOTAL 896 3910 22.92%


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