Masking unwanted areas
When an image is corrected for radiometric and geometric distortions, areas that are not of interest for the mapping purpose can be masked out. Such areas are: land, deep water, clouds, shadows.
This can be done by:
- Using existing map or GIS files of the feature to be masked
- Using band ratios to extract the shaded areas
- Using band ratios to extract deep water
- Delineating areas to be extracted
Geometric corrected image
Masking: Image of shallow sub-tidal and inter-tidal areas where land and deep water are masked out.
