REMOTE SENSING DATA

EXPLOITATION IN THE

SECURE SOCIETIES PILOT

2nd BDE Hangout “Big Data in Secure societies”21 April 2016

Michele Lazzarini, EU SatCen

RTDI Project Officer

Why Earth Observation (EO) data are Big

Data?

EO data are showing an unprecedented scenario

o Volume: Tb of EO data received each day from satellites

o Variety: Data coming from different EO sensors

o Velocity: Data to be delivered timely to users requiring fast responses

o Veracity: Decision making and operations require reliable sources

o Value: Information to be provided has to be clear and useful

Datasets for Security also composed by data from other sources…

C.Reck, G.Campuzano, K.Dengler, T. Heinen and M. Winkler, “German Copernicus Data Access and Exploitation Platform”,

Big Data from Space Conference, 15-17 March, Santa Cruz de Tenerife (ES), 2016.

BigDataEurope Pilot

Remote Sensing Big Data Platform Social Sensing

• Input (Data Access)

• Pre-Processing (Calibration

and Co-registration)

• Change Detection

• Output (Visualization)

• Monitor News

• Event Analysis (cluster,

enrich, store)

• Extract AoI

• Comparison with change

detection and visualization

Change Detection Workflow

Event Detection Workflow

Change Detection

Workflow

Event Detection

Workflow

Common

Workflow

Pilot Change Detection Workflow

Input

(Data Access)

Calibration

Co-registration

Change detection

Output

(Visualization)

The change detection workflow starts with ingestion

of satellite images

A set of operations (calibration and co-registration)

is performed to create a stack (time series) of data

Appropriated algorithms are applied to detect

areas with changes on land cover by using change

detection and characterization techniques

The identified Areas of Interest are then associated

with social media and news items and presented to

the end-user for cross-validation

Input: sensor type

SAR (radar) Optical

Input: Sentinels

Sentinels data are free and open, available from the Sentinel Scientific Data Hub

or other Collaborative Data Hubs

SENTINEL-2A (to be used in the second phase)

Launched in 2015 (Sentinel-2B lunch planned

mid-2016)

Optical sensor

Ground resolution from 10 to 60 m

Rep. cycle: 10 days with one satellite,

5 days with 2 satellites

SENTINEL-1A

Launched in 2014 (Sentinel-1B lunch

scheduled on 22nd of April 2016)

SAR sensor

Ground resolution of 5 x 20 m

Rep. cycle: 12 days with one satellite,

6 days with 2 satellites

Input: Sentinel 1

All weather capabilities

(even with clouds)

Day and night acquisition

Difficult to interpret (i.e.

ascending and descending

orbits, geometric effects)

Calibration

(Radiometric) calibration consists in linking pixels intensities to a physical parameter.

This operation is necessary to compare two or more images in a time series.

Same area, acquired from two different angles, looks different

Co-registration

Geometric correction

and co-registration of

an image stack consist in

the conversion of data in

a common ground

coordinates system in

order to:

Removal of

distortions from

sensor geometry

Enable to mapping

it with other

geographic data

Change detection and characterization

Input Output

Conclusions and future works

Input

(Data acquisition)

Calibration

Co-registration

Change detection and

characterization

Output

(Map of changes and

identified features)

Sentinel 1A GRD images are currently acquired from the Sentinels Data

Hub; Sentinel 1A SLC, Sentinel 1B and Sentinel 2 images will be added

in the data acquisition step

Sentinel 1 calibration algorithm has been deployed based on SNAP*

algorithm

Sentinel 1 co-registration algorithm has been deployed based on SNAP

algorithm

Sentinel 1 change detection algorithm has been deployed based on

SNAP algorithm, in-house tools to change detection and characterization

are currently under development

Output Binary map (changes/no changes) is available, other output

formats are under development*http://step.esa.int/main/toolboxes/snap/

UNCLASSIFIED / FOR OFFICIAL USE ONLY

European Union Satellite Centre © 2016

Michele LazzariniRTDI Project Officer

michele.lazzarini@satcen.europa.eu