Projection to Generate P-Products
Projection to generate P-Products
The VGT Level-2 data exhibit an ortho-geolocation grid defining longitude, latitude and altitude for each pixel. For resampling onto the VGT P grid, the direct and inverse geo-location approximations in the VGT Level-2 grid are needed.
The SPOT VGT Plate-Carrée grid has 112 pixels per degree, which corresponds to an equatorial resolution of approximately 1 km. The projection of the VGT Level-2 product results in the VGT-P product.
The latitude and longitude coordinates of each pixel are taken into account to fill the Plate-Carrée boxes.
The projection algorithm is then based on the same method than the one applied in PROBA-V algorithm : a stretched bi-cubic interpolation from the center of each target pixel. Status map flags are also derived from the same combining methodology.