Infrastructure

This section gives an overview about what is needed to run pre-processing / homogenization jobs of gms_preprocessing on your machine.

ECMWF database

The atmospheric correction implemented in gms_preprocessing (SICOR) uses ECMWF data (European Centre for Medium-Range Weather Forecasts) to model the atmospheric state for each scene processed.

These data are …
  • either downloaded during runtime for the current scene to process,

  • or downloaded in batch for specific time intervals before running gms_preprocessing.

To be able to download the data, you need to create an account for the ECMWF Web API and save a file called .ecmwfapirc to your home directory that contains your access token. See here for further details.

The file path of your local ECMWF database (which is automatically created by gms_preprocessing when downloading ECMWF data) can be set with a configuration parameter of gms_preprocessing.

PostgreSQL metadata database

GeoMultiSens interacts with a PostgreSQL database that contains all the satellite image metadata for all datasets that can be processed. Apart from that, it contains system-wide configuration parameters and some statistical data.

The database consists of the following tables:

Table

Description

config

system-wide configuration parameters for GeoMultiSens

datasets

records of datasets supported by GeoMultiSens

footprints_sentinel2_granules

spatial footprints of Sentinel-2 granules

jobs

processing and analysis jobs and their attributes

mgrs_tiles

spatial footprints of MGRS (military grid reference system) tiles

mgrs_tiles_proc

records of already processed MGRS tiles

satellites

records of satellites supported by GeoMultiSens

scenes

records of satellite image metadata

scenes_proc

records of already processed satellite images

scenes_sentinel2

separate table for Sentinel-2 metadata

sensors

records of sensors supported by GeoMultiSens

spatial_ref_sys

records regarding the spatial reference system

stats_mem_usage_homo

memory usage statistics for different job configurations

subsystems

records of subsystems supported by GeoMultiSens

virtual_sensors

records of target sensors of the spectral and spatial homogenization