Barcelonnette10/2013

STAGE INSTRUMENTAIRE MASTER 2

3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

WHAT?

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Understand the basic principles of multi-view photogrammetry

Learn the steps involved in the processing workflow

Get to know and handle a wide range of software (Visual SFM, Meshlab,…)

WHY?

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Estimation of mass-balances is crucial for the understanding of mass-wasting processes (landslides, erosion)

Distribution of surface fissures influences hydrological processes (infiltration and drainage) and signal underlying mechanical processes

Image-based methods are can be cost-efficient and fast complements to LiDAR acquisitions, traditional topographic surveys, and traditional mapping

Relatively new techniques that sill need development and long-term evaluation for geomorphological investigations

MULTIVIEW-STEREO - OVERVIEW

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

STEP 1 – IMAGE ACQUISITION

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

STEP 2 – FEATURE DETECTION

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

STEP 3 – FEATURE MATCHING

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

- From pairwise matches a network (graph) of image matches is obtained

STEP 4 – SOLVE GEOMETRY (SFM)

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

STAGE INSTRUMENTAIRE MASTER II 10/2012

R… RotationC… TranslationF… Focal lengthX… Coordinates

STEP 4 – SOLVE GEOMETRY (SFM)

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

Sparse point cloud and camera views

STEP 4 – SOLVE GEOMETRY (SFM)

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

STEP 5 – DENSE MATCHING

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

Patch-wise iteration of 3D point generation (computational intensive!)

STEP 5 – DENSE MATCHING

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

Patch-wise iteration of 3D point generation (computational intensive!)

Point-cloud

Surface-mesh

Textured model

FURTHER STEPS

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3D SURFACE RECONSTRUCTION WITH MULTIVIEW-STEREO

STAGE INSTRUMENTAIRE MASTER II 10/2012

Scaling and georeferencing

Comparison with LiDAR

THAT’S ALL FOLKS!

PRACTICALS?

Barcelonnette10/2012