sonarscope - ifremer · line 1 line 2 line 3 iso-accuracy limit sonarscope : swath overlap...

February 2007

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SonarScopeOverview

Jean-Marie AugustinIfremer, Brest, France

Acoustics & Seismics Dept

February 2007

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SonarScope : The sonar « photoshop»

Click right to access menuand use « Author comments »

February 2007

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SonarScope : Principal or complementary tool

Sensor SonarScopeRaw data logger

GIS

Customer Bathymetry processing DTM

Customer Imagery processing

Backscatter mosaic

February 2007

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SonarScope : Tree domains of application

• Quality control

• Data processing

• Help for interpretation

February 2007

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SonarScope : Multilayer data

Tx Sector

Beam #

Range ; time ; sample#

Depth Reflectivity

Incidentangle

And also (e.g.) :• Detection type (amplitude/phase)• Transmit angle• Mode, roll, pitch, heave…• Etc.

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SonarScope : Example of multilayer data

Tx Angle TxBeamIndexReflectivityDepth

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Artefacts

SonarScope : QualityControl

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Limits of Tx beams

SonarScope : QualityControl

Port Tx beamStarboard Tx beam

Central Tx beam

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SonarScope : Quality Control

Starboard Tx beamPort Tx beam

Central Tx beam

• Multi-layer statistics : mean of reflectivity vs Tx Angle grouped by Tx sectors

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Compensated image

SonarScope : QualityControl

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SonarScope : QualityControl

Raw Data Compensated Data

EM300 data, Calimero Grid size : 2,5 m

February 2007

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SonarScope : Quality Control

• Multi-layer statistics : Bathymetry minus tilted plan vs RxBeamIndex grouped by TxBeamIndex

February 2007

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SonarScope : Data Processing

• An abstraction model for all MBES andSidescan sonars�Transmission beams�Reception beams�BS�TVG, NE, Insonified Area, etc …

• An abstraction model for sonar data�Geometry�Data information

February 2007

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SonarScope : Data Processing

• All geometry transformations

GeoYX

PingSamplesPingBeam

LatLong

PingSwath

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• Each swath line is a mosaic image

• The Tx angle is « mosaicked »

• A pixel replaces another one only if the absolute value of its transmission angle is lower than the resident pixel : lines are separated by the iso-accuracy limit

Depth accuracy(% of errors)

θθθθOverlap area

Line 1 Line 2 Line 3

Iso-accuracy limit

SonarScope : Swathoverlap processing

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Transmission angle mosaic

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DTM with overlap

processing

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DTM without overlap

processing

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SonarScope : Help for Interpretation

• Multiple format exportation, Free viewers,WMS data importation

• Statistic compensations• Calibration• Signal processing

�Speckle filtering�Texture analysis & segmentation�BS model�Sand ripples analysis

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SonarScope : Multiple input/output data formats

Caraibes

SonarScope

ErMapper

CFloor

IRAP

Fledermaus(restricted)

Surfer

Kongsberg .all

Reson .s7k

GoogleEarth Nasa worldWind

GMT

WMS Servers

tif, jpg, bmp…

February 2007

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SonarScope : GoogleEarthformat

© Ifremer

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SonarScope : NasaWorldWindformat

© Ifremer

February 2007

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SonarScope : NasaWorldWindformat

© Ifremer

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SonarScope : Statistic compensation

© NIWA, NZ

February 2007

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SonarScope : Speckle filtering

Swansea wreck.Klein 5500 sonar.

Courtesy of DGA/GESMA

Original Despeckled

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SonarScope : Speckle filtering

Swansea wreck.Klein 5500 sonar.

Courtesy of DGA/GESMA

Original Despeckled

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SonarScope : Speckle filtering

Original Sar Image © Ifremer

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SonarScope : Speckle filtering

Original Sar Image © Ifremer

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SonarScope : Segmentation

Segmentation variationnelleτ=6,9%

Segmentation manuelle(Axel Ehrhold Rebent project)

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SonarScope : Segmentation

Segmentation manuelle(Axel Ehrhold Rebent project)

Segmentation bayésienneTw = 7x7 τ=12,5%

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SonarScope : Segmentation

Segmentation manuelle(Axel Ehrhold Rebent project)

Segmentation bayésienneTw = 33x33 τ=13%

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SonarScope : Segmentation

Dépendance angulaire du niveau d’énergie

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SonarScope : Segmentation

Dépendance angulaire de la texture

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SonarScope : Segmentation

Segmentation sansdépendance angulaire

Segmentation avecdépendance angulaire

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SonarScope : Reson-SAT2

•Reson 7150 24 kHz bathymetry : a forest of artefacts

© Ifremer

February 2007

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SonarScope : Reson-SAT2

•Reson 7150 24 kHz bathymetry after a preliminary spikeremover

© Ifremer

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• 2005-2006 : partnership agreements with�NIWA (New-Zealand)

�CHS (Canada)

�CIDCO (Canada)

�SHOM (France)

�ENST (France)

• 2007 : commercial product

SonarScope : External diffusion