The pixels are then assigned to the nearest cluster vector in Euclidian terms, and new cluster vectors are calculated based on the position of the assigned pixels. The procedure is repeated until very few pixels change clusters. Therefore, this procedure is very similar to the aforementioned K-mean clustering, except that ISODATA allows for different numbers of clusters (merging). The benefit of using this method is that it is possible to reduce the data complexity whilst retaining as much of the variance as possible. The result is the reduction of the dataset containing four spectral bands into a dataset containing only 20 classes, as shown in Fig. 5. The number 20 is based on a limitation of the WICS method: more