Variances and covariances are computed for M bands in the map list. The result is presented as a M x M covariance matrix.
The values of the covariance matrix are calculated according to the following formulae:
where:
xb |
= |
pixel values in map b. |
N |
= |
the number of pixels which are not undefined. |
and
where:
xb1 |
= |
pixel values in map b1. |
xb2 |
= |
pixel values in map b2. |
N |
= |
the number of pixels which are not undefined. |
See also: