Sen2Like: a processor for harmonising and fusing optical imaging data

Kurzfassung

Earth Observation (EO) is becoming a vital source of information for land surface monitoring. The concept of Virtual Constellation (VC) is born with the increasing number of satellites / sen-sors in operation, sensors having the same characteristics. The creation of a single VC is intend-ing to offer many new possibilities for most application domains, in particular in the fields of monitoring and change detection. In this context, this paper describes the Copernicus Sen2Like software, a solution for harmonizing and fusing Landsat 8 / Landsat 9 data and Sentinel-2 data. The Copernicus Sen2Like software process a large collection of Level 1 / Level 2A products and generates highly qualified Level 2 Analysis Ready Data (ARD) products as part of an harmo-nized (Level 2H products) and/or fuzzed (Level 2F products) spatio-temporal dataset. For these purposes, we re-used and developed a broad spectrum of pre-processing / processing method-ologies including geometric co registration, atmospheric corrections, spectral co-registration, Bi-directional Reflectance Distribution Function (BRDF) corrections and up scaling to 10.0 meter for relevant Landsat bands. The Sen2Like software has been developed as a VC framework. It is therefore a convenient tool to compare processing algorithms together. It is also opportunity to appreciate efforts required to integrate a new mission such as spaceborne, airborne, uav mis-sions. The validation activities show that the proposed approach improves temporal consistency of multi temporal data stack and output products are interoperable with subsequent thematic analysis process. This software solution is based on free and open-source libraries and is public-ly available from https://github.com/senbox-org/sen2like