- Click Geoprocessing on the Main menu of the application you are using and click Environments.
- Click Raster Storage.
- The Calculate statistics check box is checked by default. If you previously unchecked it, check it.
- Type a value for the skip factor in the x and y direction.
If, for instance, you type a value of 2 for both, every other pixel will be skipped while calculating statistics. A skip factor of 1,1 ensures full, accurate statistics.
- If there are values in the raster that you want to ignore while calculating statistics for the raster, type their values, separated by a semicolon (;).
These values are frequently background values, which often have a value of 0. Eliminating such a value can result in a more accurate, and perhaps more representative, calculation of statistics. If you have specified a specific pixel value as NoData, you will not be able to specify it as an ignore value.
- Click OK to close the Environment Settings dialog box.