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Figure 5.19 Algorithm for texture extraction using MAR algorithm.

Figure 5.20 Typical shape of a semivariogram over different lags h.

Two methods of using the semivariogram are described by Atkinson and Lewis (2000). The first method uses the semivariogram values directly. Two windows are defined. The first is a larger window that contains the second, smaller window. The larger window has dimensions of l×m, and within this area a subwindow of size r×s is used to estimate semivariances for all possible lags (i.e. up to r–1 or s–1, whichever is the greater). The mean semivariance and the standard deviation of the semivariances for the subwindows is used as texture measures. Chica-Olmo and Abarca-Hérnandez (2000) describe an example of the use of this approach to tex

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