Glossary for Geospatial Science

data mask:  A processing barrier that only allows data values in a chosen range to pass.  You might choose a data mask to block all values outside a selected color range, eliminating all image features except those of the color you want to use in a process.  You can also use a mask to select a processing area from a larger scene.  The mask blocks off the parts that you want to exclude from the current analysis.