dense dsms from stereo imagery
DESCRIPTION
Dense DSMs from Stereo Imagery. IMAGE. Dr. Philippe Simard President SimActive Inc. About SimActive. Founded in 2003, SimActive is the developer of Correlator3D™ software, a patented end-to-end photogrammetry solution - PowerPoint PPT PresentationTRANSCRIPT
IMAGE
Dense DSMs from Stereo Imagery
Dr. Philippe SimardPresidentSimActive Inc.
About SimActive
Founded in 2003, SimActive is the developer of Correlator3D™ software, a patented end-to-end photogrammetry solution
SimActive has been selling Correlator3D™ to leading mapping firms and government organizations around the world
Correlator3D™ is the fastest commercial software to perform DSM generation
DSM DTM Mosaic 3D Features
Correlator3D™ Software
DSM Generation
EO Refinement
Mosaic Creation
DEM Editing
Orthorectification
DTM ExtractionMicrosoft Ultracam
Applanix DSS
DiMAC
Intergraph Z/I DMC
VM A3 Mosaic Editing
PROCESSING MODULESIMAGERY
ADS80
Scanned Films
Aerial
GeoEye
ALOS Prism
Cartosat-1
Worldview
Quickbird
Ikonos
SPOT
Satellite
Feature Extraction
DSM Generation
A Digital Surface Model (DSM) is a representation of ground topography
Main Processing Steps: 1. Correlation 2. Triangulation
Bottom-up approach
What is it?
DSM Example
TriangulationCorrelation
Focal point
Image 1 Image 2
Epipolar
Traditional approach: How does it work?
DSM Generation
DSM
What is it?
A dense DSM has a grid post spacing approaching the ground sampling distance (GSD) of the input imagery
Dense DSM Generation
SimActive has just released its next generation DSM engine capable of producing dense DSMs
Dense DSM
Challenges
1. Correlation
2. Sensitivity
3. Density
Process more difficult
Radiometry differences between images Camera calibration Exterior orientation
More points leads to longer processing time
For dense DEM generation
Bottom-Up Derive solution
Feature-Based High density in
some areas only
CPU Few cores
Comparison
Traditional Top-Down
Test solutions
Grid-Based High density in all
areas
GPU Hundreds of cores
SimActive
Focal point
Image 1 Image 2
Top-Down
Idea: test solutions and check whether they solve the correlation problem
Grid-Based
Grid-based DEM is dense everywhere
No interpolation
Correlation performed on all points in the grid
Adjacent solutions assist each other
GPU
Possible Solutions Processing ResultsP11
P21
... Pn1
P12
P22
... Pn2
... P1n
... P2n
...Pnn
GPU Cores
These solutions are processed by the GPU simultaneously
When a match is found, the problem is solved
1 2 3
Many possible solutions are prepared to be tested1
2
3
Results
Resolution: 25 cmAccuracy: 5 cm
Resolution: 15 cmAccuracy: 5 cm
Dense DSMDSM
Benefits
World’s fastest commercially available DSM engine
Direct DSM result removing the need to convert from a point cloud
More points in low texture areas
DSM precision is consistent and homogeneous
Dense DSM
Applications
Dr Philippe SimardPresidentSimActive [email protected]
Thank You
Official ResellerGroupe SCE IndiaMahesh Nagendra JMobile: +91 [email protected]