Photogrammetry and Laser scanning · •Aerial Laser Scanning (ALS) - Topographic ALS is a laser...
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Photogrammetry and Laser scanning (PLS) 4 th Stage Overview Dr. Fanar Mansour E-mail : [email protected]
Transcript of Photogrammetry and Laser scanning · •Aerial Laser Scanning (ALS) - Topographic ALS is a laser...
Photogrammetry and Laser scanning (PLS) 4th Stage
Overview
Dr. Fanar Mansour
E-mail : [email protected]
Digital Photogrammetry
• Objective
Derive the position and shapes of objects from digital
photographs.
• Platforms - Aerial
- Terrestrial/close range
Digital Photogrammetry
• Image Registration - Objectives
Integrate data from different
sources of multi-temporal,
Multi-sensors, multi-types,
Multi-resolution.
Digital Photogrammetry
• Image Georeferencing - Objectives
Tie image coordinate system with
Ground coordinate system.
(2D to 3D) relation!
Digital Photogrammetry
Digital Photogrammetry
• Post-processing: Digital photogrammetric workstations (DPW/DPWS/DPS).
• DPW: hardware and software to derive photogrammetric products from digital photographs/images using automated techniques, e.g. SocetSet from BAE Systems.
Digital Photogrammetry
Digital image matching: - By interest points
- By window
- By feature
Digital Photogrammetry
• Products: - Mosaic image
- Ortho image
Digital Photogrammetry
• Digital Terrain Model
- DSM vs DTM
Digital Photogrammetry
Aerial Photographs of a roadway Digital terrain model of the roadway
Digital Photogrammetry Applications:
Digital Photogrammetry Applications:
Topographic mapping Archaeology
3D city modelling
Digital Photogrammetry Applications:
Digital Photogrammetry Applications:
Laser scanning
• Laser scanning, also referred to as lidar (light detection and ranging) is the digital technique of capturing accurate information about physical objects using laser light (Wagner, 2005).
• Platforms:
• Typical components of laser scanning systems:
- Laser scanner
- GPS
- IMU
Laser scanning
Coordinate systems and parameters involved in the Lidar equation
Laser scanning
ALS TLS
need for a geometric calibration?!
• Aerial Laser Scanning (ALS) - Topographic ALS is a laser scanning system mounted on an
airborne platform and provides range measurements to the Earth’s surface.
- It delivers a vertical accuracy of 5-10cm and decimetre-level planimetric accuracy, depending on the terrain type and flying height.
- Land cover features are scanned either from a fixed wing or a helicopter platform.
- Digital camera is usually flown alongside the ALS systems for orthophoto generation and data integration.
- Commercial ALS systems typically operate at wavelengths between 800 and 1550 nm.
Laser scanning
Photogrammetry vs. Laser scanning
Laser scanning/ALS data
Morpeth flooding project
Laser scanning/ ALS - classification
Laser scanning/ ALS - segmentation
• Terrestrial laser scanning (TLS)
Laser scanning
References • Kraus, Karl, Photogrammetry-Geometry from images and laser
scans, 2nd ed., Walter de Gruyter, Berlin, 2007.
• الطبعة ،التحليلي التصويري المسح ، البكري ميثم ، منصور فنار ،عباس سليم بشار 2009 الاردن ، والتوزيع للنشر اثراء ، الاولى
• Wolf, Paul.R. and Dewitt, Bon A.,Elements of Photogrammetry with applications in GIS, 3rd ed., McGraw-Hill,New York, 2000.
• Mikhail, Edward M.; Bethel, James S.; and McGlone, J. Chris, Introduction to modern photogrammetry, 1st ed., John Wiley & Sons, U.S., 2001.
• Topographic laser ranging and scanning, eds: Jie Shan & Charles K. Toth, 2009.
• Airborne and terrestrial laser scanning, eds: George Vosselman & Hans-G-Mass, 2010.
credits
• Geomatic Engineering department, Calgary University, Canada.
• RIEGL USA
• Civil Engineering and Geosciences, Newcastle University, UK.
• University of Glasgow, UK.
• Geosensing Engineering and Mapping (GEM), University of Florida, USA.
• ITC, University of Twente.
• Vienna University of Technology.
