Processing chains, pipelines, applications

At CNES we develop several end to end tools that can be launched using Command Line Interface (CLI) or other APIs like Python. These processing chains are used in our production centers (and by others) to provide high level products accessible to users and scientists.

This page aims at providing an overview of the main tools that are developed by CNES or widely used in our projects. This is not an exhaustive list of the tools we develop or use.

Generic tooling

The following tools are often used by others in the following paragraphs to build complex processing chains. They can be used on their own, but they are more considered as generic frameworks enabling the developement of complete pipelines.

Function	Tools	Related use cases
Generic tooling	OrfeoToolBox	Offers a lot of implemented algorithms on top of GDAL and ITK with many features like stream processing.
	Xarray	Along with all the Pangeo ecosystem around, with rioXarray or odc.geo, allows writing data processing pipelines on scientific datasets.
	OpenEO	Provides API and platform to build reproducible pipelines on infrastructures providing this backend.

Satellite time series and optical imagery

CNES and associated labs like CESBIO have an expertise in raster imagery processing. Several tools have been developed, and are used in CNES and European ground segments:

Function	Tools	Related use cases
Timeseries and Optical Imagery	MAJA	Level-2A processor used for atmospheric correction and cloud-detection.
	GeoRastertools	Command line and Python API to run various calculation tools on rasters.
	SLURP	Processes a VHR image and computes a simple land-use mask (water, low/high vegetation, bare ground, buildings).
	Iota2	Land-use map production line for large areas based on time series of Sentinel or Landsat images.

SAR processing

We have several services at CNES and associated labs dedicated to SAR and altimetry processing, which build the following tools (and plenty others):

Function	Tools	Related use cases
SAR processing	S1Tiling	On demand Ortho-rectification of Sentinel-1 data on Sentinel-2 grid.
	Tropisco	Following tropical deforestation using SAR imagery.
	DiapOTB	Orfeo Toolbox remote module that contains all necessary steps and allows to launch a complete DInSAR chain.

3D and DEM tool set

CNES has a team dedicated to developing 3D products and algorithms based on Very High Resolution imagery, like Pleiades and next generations satellites. There are also more low level tools to work with DEM or point clouds. Some of the most used processing chains or end to end tools are the following:

Function	Tools	Related use cases
3D and DEM tool set	CARS	Open source 3D tool dedicated to produce Digital Surface Models from satellite imaging by photogrammetry.
	Pandora2D	Coregistration tool that provide disparity maps for images pairs.
	DEMcompare	Python software that aims at comparing two DEMs together.
	CloudCompare	Allows to open and visualize 3D data including point clouds and meshes.

Hydrology

CNES develops processing chains and hosts a processing center for producing Hydrology variables like water masks or snow cover area in moutains:

Function	Tools	Related use cases
Hydrology processes	Let it Snow	Snow detection algorithm on various satellite products and temporal synthesis on time series of snow products.
	SurfWater	Water masks processing and other higher level products.
	GRS	Glint Removal for Sentinel-2-like sensors, used for Water quality.

Others

Of course, there are plenty other subjects of interest at CNES like Atmospheric studies or image quality. With for example the following tools:

Function	Tools	Related use cases
Hydrology processes	4A/OP	High-resolution radiative transfer model designed for atmospheric remote sensing applications.
	OSOAA	Radiative transfer model for simulating atmospheric and oceanic scattering and absorption.
	ALCD	Used to generate classification datasets with any set of categories.