Minimize Compositing to generate S1 and S10 products

Both daily and ten-day composites (S1 and S10 respectively) are produced from surface reflectance included in the VGK products, taking the NDVI previously computed during VGT-P processing into account.

The compositing is carried out on the VGT 1 km Plate-Carrée grid (see Projection to Generate P Products). The pixels incorporated into the synthesis are selected according to the maximum NDVI value, in order to ensure coverage of all landmasses worldwide with the minimum effect of cloud cover.

 

In the frame of coming evolutions, the composite method used to create VGT-S product could be modified to ensure continuity to VGT and Proba-V service. Two options are under investigation:

  1. Analyse the more adequate composite method between several known technics ( the Best Index Slope Extraction or Mean Compositing methods, …) and implement it in the VGT-S processing
  2. Update the NDVI computation and discuss the "max NDVI" composite method