Cloud masking

Sentinel-2 cloud masking

The exclusion of clouds and cloud shadow is an important processing step which is usually done in an early preprocessing stage. The Sentinel-2 products are annotated with Quality Indicators (QI_DATA). In the Level 2A product you may find a file in the folder QI_DATA with the extension _CLD_20m.jp2 (data type: 8bit unsigned integer, spatial resolution 20m) which might be used for masking clouds. The data range is from 0 for high confidence clear sky to 100 for high confidence cloudy. L2A Product Definition Document https://earth.esa.int/documents/247904/685211/S2+L2A+Product+Definition+Document/2c0f6d5f-60b5-48de-bc0d-e0f45ca06304