About CASOAR  

CASOAR : Introduction

Initialy designed by Thierry Souriot (CNRS 2007-2012).
Web Manager Yannick GUEHENNEUX
Please contact : Y.Guehenneux for technical questions,
and J.L.Froger for scientific questions.

Last update 2019/06/19 (all dates are in YYYY/MM/DD format).

Introduction - Acknowledgements - User's guide - Know bugs - History - Access and User Charter

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CASOAR is a tool dedicated to sorting, selecting, visualizing and sharing large-radar-images-databases. It includes a set of processing components and a WEB interface. It was initially designed for the co-investigators and ESA research project partners to access SAR and InSAR images, but it could easily be upgraded for various satellite image types such as SPOT, LANDSAT, ASTER, etc. Currently, CASOAR integrates radar data (~ 1200 RAW/SLC images & ~ 3000 interferograms) acquired in the framework of 6 main projects (ESA AOE.746, AOE. 857, C1P.2899, AOALO.3622, AO for Turkey 2446, DLR LAN.O237).

Data Processing

Firstly the new data is extracted, formated, processed and recorded of new data onto the database. This part of CASOAR is mainly written in C and shell scripts and also uses external software and libraries such as NEST (ESA), DIAPASON (Altamira©), ImageJ, ImageMagik, Manip_Raster , etc... At this step, particular attention was given to achieve maximum automation of the procedures so that the updating and maintenance of the database requires minimal operator intervention.

Web Interface

The second component of CASOAR consists of a WEB interface developed in PHP, MySQL and Google API. This interface allows partial or total access to the database by means of a login/password connection with different levels of permissions.

Project, Group, User and Security

CASOAR security is ensured by means of dividing the database into projects, visible only by authorised groups and users. Each user has his own login/password allowing access to specific projects and specific data or images in the project. The user connection history is recorded and is visible only to the database administrator. Login/Password are provided on request (use the Registeration button on the connection page). The registeration validation procedure may take few days since it is not fully automated.

Anonymous access is possible but with more restrited rights, such as lower resolution and tagged images, and only images are only available for the OI2 project.

Data Visualisation

The images selected can be presented either in a parameters table, a location map or via different levels of quick looks. Clicking on a given quick look opens it in a new window with a higher resolution and a list of relevant information.


Map Google API

Image preview
Automatic functionalities:
  • Network survey and downloading of data (e.g. : Doris orbit on FTP server)
  • Data and metadata extraction and conversion from original files
  • Database update and notification email
  • Interferograms computation, using an automated procedure based on the DIAPASON software (Altamira©)
  • Physical and/or network backup
Available data types :

Available : (numbers are in real time)

Planned :

  • ERS SAR 1 & 2 raw : 287 images
  • ERS SAR 1 & 2 interferrogram : 0 images
  • RADARSAT 1 & 2 SLC : 85 images
  • RADARSAT 1 & 2 interferogram : 118 images
  • ENVISAT ASAR SLC : 887 images
  • ENVISAT interferogram : 5044 images
  • ENVISAT MERIS : 107 images
  • ALOS PALSAR SLC : 754 images
  • ALOS PALSAR interferogram : 778 images
  • TerraSAR-X SLC : 373 images
  • TerraSAR-X interferogram : 1172 images
  • COSMO-SKYMED SLC : 275 images
  • COSMO-SKYMED interferogram : 2828 images
  • Information
  • DEM
  • SPOT
  • Aerial photography
Utilities :

IMPORT/EXPORT of selection parameters

CASOAR saves active selection parameters for each user at the end of his session and automatically restores them at the beginning of the next user login. It is also possible to save the selection parameters at any time during the session in a CASOAR file (.kzr). CASOAR files can then be shared with other users.


Another way to register a selection is by adding the data into the Desirables icon. The Desirables function is accessible both at the TABLE selector level and at the image preview level. It can be used by the co-investigators to request full resolution data which will then be automatically downloaded by our FTP server.

Future improvements

We are planning to integrate new data format and new function into CASOAR, for example, dynamic statistic analysis of interferogram subsets.

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The following people have contributed to the production of the data displayed in CASOAR :

  • J.L. Froger, S. Byrdina, and Th. Souriot in various project.
  • F. Albino, K. Gonzales, and D. Remy for ENVISAT and ERS ASAR interferograms in the VolInSAR_AS project.
  • F. Ranvier for ERS ASAR interferograms in the VolInSAR_ET project.
  • P. Tinard for ENVISAT ASAR interferograms in the OI2 project.
  • D. Tolluoglu for ENVISAT and ERS ASAR interferograms in the VolInSAR_TK project.

Scientific programs which have provided us with satellite data used in CASOAR :

  • ERS and ASAR-ENVISAT images of South America were provided by the European Space Agency through project ENVISAT-AO #857 and Category-1 #2899.
  • ERS and ASAR-ENVISAT images of Etna were provided by the European Space Agency through project ERS-AO3 #999257, ENVISAT-AO #857 and Category 1 #1125.
  • ERS and ASAR-ENVISAT images of Turkey were provided by the European Space Agency through project AO for Turkey #2446.
  • ASAR ENVISAT images of Piton de La Fournaise were provided by the European Space Agency through project ENVISAT-AO #746 and ALOS ADEN #3622.
  • MERIS ENVISAT images of Piton de La Fournaise were provided by the European Space Agency through project ENVISAT-AO #746
  • PALSAR ALOS images of Piton de La Fournaise were provided by the European Space Agency and JAXA through project ALOS ADEN #3622
  • TerraSAR-X images of Piton de La Fournaise were provided by DLR to CNES through project KALIDEOS - BD-ISLE DLR LAN #O237.
  • RADARSAT-2 images of Piton de La Fournaise were provided by CSA-MDA through project ASC SOAR #2314

We thank the ANR, INSU, IRD, FONDECYT/CONICYT, and OPGC for funding support.

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