Terrestrial remote sensing toolkit

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BRG The University of Queensland
Fundamentals

- Main page
- Pre-processing
  - Image acquisition
  - When to correct
  - Correction types
  - Masking
- Field data collection
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# 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: 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 NIR band to extract water as it does not penetrate water
- Delineating areas to be extracted

Geometric corrected image
Masking: Image of land without water and clouds.