Extraction of 3D Geo-information from
Cartosat images and it’s Visualization
Amitabh, B. Gopala Krishna and Pradeep K Srivastava
Amitabh
Scientist / Engineer-SE
Space Applications Centre (ISRO)
Ahmedabd-380015
[email protected]
Contents
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Introduction
Cartosat-1 & 2 Specifications
DEM Generation
Methodology Adopted for Mapping
Comparative study of features from Carto-1
Comparative study of features from Carto-2
Visualisations
Conclusion
Introduction
3D Geo-information in the form of Digital
Elevation Models (DEMs) and 3D Features
are at the core of most environmental
process modeling and disaster management
Cartosat-1 & 2 Specifications
Cartosat-1 Sensor Characteristics
Cartosat-1 Obit Characteristics
Cartosat-2 Specifications
Cartosat-2 Sensor Characteristics
Yousufguda (Hyderabad)
Mahatma Gandhi Bus
Station Hyderabad
Cartosat-2 Obit
Characteristics
•Mono / Strip Imaging
•Paint Brush Imaging
Study Area & Input datasets
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A part of Hyderabad City
Two stereo pairs of Cartosat-1
10 GCPS and 10 ICPS
One Image of Cartosat-2
AFT
Path/Row: 544/315
DOP: 08 June 2005
FORE
Cartosat-2 Image
AFT
Cartosat-1 Stereo Pairs
FORE
Path/Row: 544/316
DOP: 08 June 2005
Methodology
Visualisation
DEM & Ortho-image Generated
Min.: 315m
Max.: 619m
Grid: 10 m
Pixel Size: 2.5 m
Painted relief and overlay
315m
Bin=15 m
630m
DEM, Orthoimage and Relief Overlay
DEM Accuracy
Comparison Graph
700
600
Height
500
400
SRTM
GPS
300
CARTODEM
200
100
0
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2
3
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Point No.
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Feature List
S. No.
Level-1
Mode of Feature
Extraction
Level-2
1
Communication Line
2D (C1 & C2)
Road with Trees
National Highway
City Roads / Streets
Cart Track
Railway Line
Rail under Construction
Road Under Construction
2
Construction
2D & 3D
Building / Building Blocks
Houses in Rural Area
Stadium
Aerodrome
Railway Station
Industrial area
3
Hydrography
2D (C1 &C2)
River / Stream permanent
River / Stream Temporary
River with trees
Canal
Lake / Pond / Water bodies Permanent
Lake / Pond / Water bodies temporary
Barrage / Reservoir
4
Orographie
3D (C1)
Index Contour
Contour Normal
5
Vegetation
2D / 3D
Vegetation Limit
Forest
Plantation / Trees
Comparative study: Features from Cartosat-1
Carto-1
Comparison of features extracted in 2D
and 3D mode from Carto-1 (Red: 2D &
Blue:3D)
Carto-2
Comparative study: Features from Cartosat-2
Comparison of features
extracted in 2D mode
(pink: Cartosat-1 & Blue:
Cartosat-2)
Visualisations
Anaglyph
Polarized Stereo
2.5 D (Drape)
Conclusion
• The radiometry of Cartosat-1 & 2 Images are
very good and suitable for mapping
• Cmfortable stereo viewing & effective image
matching
• No Streaking, banding, saturation, noise and
other radiometric artifacts
• The RPC model with GCPs provides the
positional accuracy within one pixel and DEM
accuracy 4m.
• Combination of C-1 & C-2 provides the vital
mapping layers for various applications
Feedback / Query
[email protected]