SNAP-Sentinel-1 in a Nutshell

Dr. Andrea Minchella

1st ESA Advanced Training Course on Remote Sensing of the Cryosphere13 September 2016, University of Leeds, Leeds, UK

SNAP in a Nutshell

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What is SNAP?

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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Sentinel Toolboxes Consortia

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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Toolbox Evolution

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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Toolbox Evolution

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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Architecture Highlights

• Java, Python implementation

• Snap desktop: integrated graphical user-friendly interface;

• Snap engine (Graph Processing Tool): core and command line interface;

• Graphical or command-line execution;

• Tiled memory management for working with very large data products;

• Data abstraction models to handle all SAR missions in a common way

• Modular design for easy modifications and upgrades

• Users are able to add their own modules via APIs

• Multithreading and Multi-core processor support

• Integrated WorldWind visualisation

SNAP in a Nutshell

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Supported Platforms and Source Code Repository

Credit: Sentinel-1 Toolbox – Open Source Tools for EOScience 2.0 @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

• 32bit/64bit

• Windows (XP, Vista, 7, 8, 10)

• Linux

• Mac OS X

SNAP in a Nutshell

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Graph Processing Tool

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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SNAP Applicaton Modes

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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Generic Functions and Tools

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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STEP (Science Toolbox Exploitation Platform)

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

https://step.esa.intEOSciencecollaborativeplatform

• SNAPsoftwaredownload

• SNAPtutorialsanddocumentation

• Technicalforumandcommunityanimation

• Gatheringuserfeedbackandusage

Classification: CATAPULT OPEN

Example of Sentinel-1 data processing

Sentinel-1 toolbox architecture: data flow

Snapdesktop(GUI)IntegratedgraphicaluserinterfaceforSARdatavisualisation,

analysisandprocessing

GraphProcessingTool(GPT)Forcommandlineexecutionofuser-defined

batchprocessingchains

WritersReaders GenericProductModel(GPM)

Sentinel-1ENVISAT ASAR

ERS-1&2

Radarsat-2

Cosmo-SkyMed

TerraSAR-XTandem-x

ALOS PALSAR1&2

Radarsat-1

JERS SAR

Beam dimap

Geotiff

Netcdf

EnviGeneric BinaryGoogle EarthPolSARpro

etc

SNAP in a Nutshell

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Generic Functions and Tools

• Statistics & Data Analysis

• Metadata handling

• Subset, Resample and Band Arithmetic

• Export to GeoTiff, HDF 4 & 5, NetCDF, Bynary, Envi, Kmz formats

• LUT and Layer Management

• ROI tools, layer stacking

• ….

SNAP in a Nutshell

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Main SAR Functionality

• Left and right facing missions displayed by start time and near range• Absolute calibration • Multilooking• speckle (single and multitemporal) filtering• Precise orbit handling (Doris, Prare and Delft orb.)• Coregistration of detected and complex products• Debursting of ASAR WSS• Range-Doppler Terrain Correction• Radiometric normalization during Terrain Correction• SAR simulation• Layover and shadow masks• Simulated SAR Terrain Correction• Ellipsoid correction, Map Reprojection, Mosaicking• Automatic DEM download and tile selection• Product library for scanning and cataloguing large archives efficiently

SNAP in a Nutshell

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Main SAR Functionality

- SAR Applications:

Ø Ocean tools: basic routines for oil spill detection, ship detection and wind field estimation from SAR data

Ø Urban Areas: Speckle Divergence

Ø Offset tracking

Ø Change detection

Levelofsupportdependsonsensor&producttype.PleaserefertodocumentationforfulldetailssuchastheOperatorshelp

- Inteferometry for Strimap and Zero-Doppler focused data

- Compatibility with ESA PolSARpro Toolbox (Reader, Writer)

SNAP in a Nutshell

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Ocean Tools

Land Masked Detection Map Projected

• Object (ship) Detection • Oil Spill Detection

• Wind Field Estimation

• Create Land Mask

SNAP in a Nutshell

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InSAR

Architecture Highlights

• Coregistration and resampling

• DEM assisted coregistration

• Products: interferogram and coherence

• Filtering: both spectral and phase

• Geo-coding

• Unwrapping via 3rd party sw(SNAPHU)

• Phase to height conversion

• Differential InSAR

• Cross InSAR (ERS-ENVISAT)

Only zero doppler and strip map data are fully supported

SNAP in a Nutshell

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New Sentinel-1 Functionality

• Calibration

• Thermal Noise Removal

• Slice Assembly

• TOPSAR Deburst and Merge

• GRD Border Noise Removal

• TOPSAR Interferometry

SNAP in a Nutshell

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New Level-2 OCN Visualisation

Credit: Sentinel-1 Toolbox – Open Source Tools for EOScience 2.0 @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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Polarimetric Tools

QuadPolDecompositions• Sinclair• Pauli• Freeman-Durden• VanZyl• Yamaguchi• Cloude• H/AAlpha• Touzi

DualPolDecomposition• H/AAlpha

SNAP in a Nutshell

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Quad Pol & Dual Pol Functionality

Credit: SNAP – The Sentinels Application Platform @ ESA EO SCIENCE 2.0 Workshop, 12-14 October 2015, ESA-Esrin, Frascati, Rome (Italy)

SNAP in a Nutshell

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The Product Library

• Convenient browsingandimportingofproductshavinginformation andQuick Lookproduct

• Nowhandlesopticalproducts andS-1L2OCNproducts

Any Question?