This service provides users the ability to choose Sentinel-2 bands for the processing of (Band_A) / (Band_B). The default is to use Sentinel-2 Band 8 (Near Infrared) as Band_A and Band 4 (Red) as Band_B. The default band values belong to the Ratio Vegetation Index (RVI). The RVI is a widely used vegetation index that indicates the amount of vegetation. The higher the value, the more vegetation. Low values show soil, ice, water etc. Users can choose every available band combination (see link below).
The Ratio Index service is a parallel processing service based on ESA's Sentinel-2 Toolbox. The Service is labeled "S2_BandRatio" and is to be found in the Explorer / Services tab of the Food Security TEP GUI.