-
Friedrich Ackermann.
Airborne laser scanning - present status and future expectations.
jprs,
54(2-3):64-67,
1999.
Keyword(s): airborne laser scanner,
digital terrain model,
continuous wave laser.
@Article{ackermann,
author = {Friedrich Ackermann},
title = {Airborne laser scanning - present status and future expectations},
journal = jprs,
year = {1999},
volume = {54},
pages = {64-67},
number = {2-3},
url = {},
keyword = {airborne laser scanner, digital terrain model, continuous wave laser},
abstract = {},
}
-
Peter Axelsson.
Processing of laser scanner data -algorithms and applications.
jprs,
54(2-3):138-147,
1999.
[WWW
] Keyword(s): laser scanner,
3D City Models,
classification,
modelling,
filtering,
MDL.
Abstract: |
airborne laser scanner systems are opening new possibilities for surveys and documentation of difficult areas and objects, such as dense city areas, forest areas and electrical power lines. Laser scanner systems available on the market are presently in a fairly mature state of art while the processing of airborne laser scanner data still is in an early phase of development. To come from irregular 3D point clouds to useful representations and formats for an end-user requires continued research and development of methods and algorithms for interpretation and modelling. This paper presents some methods and algorithms concerning filtering for determining the ground surface, DEM, classification of buildings for 3D City Models and the detection of electrical power lines. The classification algorithms are based on the Minimum Description Length criterion. The use of reflectance data and multiple echoes from the laser scanner is examined and found to be useful in many applications. |
@Article{axelsson99,
author = {Peter Axelsson},
title = {Processing of laser scanner data -algorithms and applications},
journal = jprs,
year = {1999},
volume = {54},
pages = {138-147},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-B/1/18e9fd7bf94a47f2c5a7f596447cf7c2},
keyword = {laser scanner, 3D City Models, classification, modelling, filtering, MDL},
abstract = {airborne laser scanner systems are opening new possibilities for surveys and documentation of difficult areas and objects, such as dense city areas, forest areas and electrical power lines. Laser scanner systems available on the market are presently in a fairly mature state of art while the processing of airborne laser scanner data still is in an early phase of development. To come from irregular 3D point clouds to useful representations and formats for an end-user requires continued research and development of methods and algorithms for interpretation and modelling. This paper presents some methods and algorithms concerning filtering for determining the ground surface, DEM, classification of buildings for 3D City Models and the detection of electrical power lines. The classification algorithms are based on the Minimum Description Length criterion. The use of reflectance data and multiple echoes from the laser scanner is examined and found to be useful in many applications.},
}
-
Emmanuel P. Baltsavias.
A comparison between photogrammetry and laser scanning.
jprs,
54(2-3):83-94,
1999.
[WWW
] Keyword(s): digital and analytical photogrammetry,
airborne laser scanner,
comparison,
DTM generation,
applications.
Abstract: |
A comparison between data acquisition and processing from passive optical sensors and airborne laser scanning is presented. A short overview and the major differences between the two technologies are outlined. Advantages and disadvantages with respect to various aspects are discussed, like sensors, platforms, flight planning, data acquisition conditions, imaging, object reflectance, automation, accuracy, flexibility and maturity, production time and costs. A more detailed comparison is presented with respect to DTM and DSM generation. Strengths of laser scanning with respect to certain applications are outlined. Although airborne laser scanning competes to a certain extent with photogrammetry and will replace it in certain cases, the two technologies are fairly complementary and their integration can lead to more accurate and complete products, and open up new areas of application. |
@Article{baltsavias99,
author = {Emmanuel P. Baltsavias},
title = {A comparison between photogrammetry and laser scanning},
journal = jprs,
year = {1999},
volume = {54},
pages = {83-94},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-4/1/fe4480c1df58aab416b9cf65090288f0},
keyword = {digital and analytical photogrammetry, airborne laser scanner, comparison, DTM generation, applications},
abstract = {A comparison between data acquisition and processing from passive optical sensors and airborne laser scanning is presented. A short overview and the major differences between the two technologies are outlined. Advantages and disadvantages with respect to various aspects are discussed, like sensors, platforms, flight planning, data acquisition conditions, imaging, object reflectance, automation, accuracy, flexibility and maturity, production time and costs. A more detailed comparison is presented with respect to DTM and DSM generation. Strengths of laser scanning with respect to certain applications are outlined. Although airborne laser scanning competes to a certain extent with photogrammetry and will replace it in certain cases, the two technologies are fairly complementary and their integration can lead to more accurate and complete products, and open up new areas of application.},
}
-
E. P. Baltsavias.
Airborne laser scanning: basic relations and formulas.
jprs,
54(2r3):199-214,
1999.
[WWW
] Keyword(s): Airborne laser scanning,
Terminology,
Basic relations,
Formulas,
3D accuracy analysis.
Abstract: |
An overview of basic relations and formulas concerning airborne laser scanning is given. They are divided into two main parts, the first treating lasers and laser ranging, and the second one referring to airborne laser scanning. A separate discussion is devoted to the accuracy of 3D positioning and the factors influencing it. Examples are given for most relations, using typical values for ALS and assuming an airplane platform. The relations refer mostly to pulse lasers, but CW lasers are also treated. Different scan patterns, especially parallel lines, are treated. Due to the complexity of the relations, some formulas represent approximations or are based on assumptions like constant flying speed, vertical scan, etc. |
@Article{ baltsavias-airborne99,
author = {E. P. Baltsavias},
title = {Airborne laser scanning: basic relations and formulas},
journal = jprs,
year = {1999},
pages = {199-214},
volume = {54},
number = {2r3},
url = {http://citeseer.nj.nec.com/article/baltsavias99airborne.html},
keywords = {Airborne laser scanning; Terminology; Basic relations; Formulas; 3D accuracy analysis},
abstract = {An overview of basic relations and formulas concerning airborne laser scanning is given. They are divided into two main parts, the first treating lasers and laser ranging, and the second one referring to airborne laser scanning. A separate discussion is devoted to the accuracy of 3D positioning and the factors influencing it. Examples are given for most relations, using typical values for ALS and assuming an airplane platform. The relations refer mostly to pulse lasers, but CW lasers are also treated. Different scan patterns, especially parallel lines, are treated. Due to the complexity of the relations, some formulas represent approximations or are based on assumptions like constant flying speed, vertical scan, etc.},
}
-
E. P. Baltsavias.
Airborne laser scanning: basic relations and formulas.
jprs,
54(2-3):199-214,
1999.
[WWW
] Keyword(s): airborne laser scanner,
Terminology,
Basic relations,
Formulas,
3D accuracy analysis.
Abstract: |
An overview of basic relations and formulas concerning airborne laser scanning is given. They are divided into two main parts, the first treating lasers and laser ranging, and the second one referring to airborne laser scanning. A separate discussion is devoted to the accuracy of 3D positioning and the factors influencing it. Examples are given for most relations, using typical values for ALS and assuming an airplane platform. The relations refer mostly to pulse lasers, but CW lasers are also treated. Different scan patterns, especially parallel lines, are treated. Due to the complexity of the relations, some formulas represent approximations or are based on assumptions like constant flying speed, vertical scan, etc. |
@Article{baltsavias99c,
author = {E. P. Baltsavias},
title = {Airborne laser scanning: basic relations and formulas},
journal = jprs,
year = {1999},
volume = {54},
pages = {199-214},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-G/1/581b2018eec715e970b19e2d36726e94},
keyword = {airborne laser scanner, Terminology, Basic relations, Formulas, 3D accuracy analysis},
abstract = {An overview of basic relations and formulas concerning airborne laser scanning is given. They are divided into two main parts, the first treating lasers and laser ranging, and the second one referring to airborne laser scanning. A separate discussion is devoted to the accuracy of 3D positioning and the factors influencing it. Examples are given for most relations, using typical values for ALS and assuming an airplane platform. The relations refer mostly to pulse lasers, but CW lasers are also treated. Different scan patterns, especially parallel lines, are treated. Due to the complexity of the relations, some formulas represent approximations or are based on assumptions like constant flying speed, vertical scan, etc.},
}
-
E. P. Baltsavias.
airborne laser scanner : existing systems and firms and other resources.
jprs,
54(2-3):164-198,
1999.
[WWW
] Keyword(s): airborne laser scanner,
airborne laser scanners (technical specifications),
airborne laser scanners (commercial firms).
Abstract: |
This article gives an overview of resources on airborne laser scanning (ALS). The main emphasis is on existing systems and firms, especially commercial ones. Through a very time-consuming search and with the help of numerous persons from firms, organisations and other colleagues, a quite complete survey of existing commercial systems, including detailed system parameters, has been compiled. This survey is by far the most complete and up-to-date information available today on commercial ALS. Additional data on contact information, links and, in some cases, a short background is given for firms involved in ALS (manufacturers, service providers, owners). A summary of other non-commercial and research systems, mainly of NASA, and respective links is presented. Finally, some other useful WEB links are given. The developments in ALS have been very rapid the last 1¯2 years. This overview reflects these developments and describes rather completely the current situation, thus, being useful for all persons involved in ALS one way or another. |
@Article{baltsavias99b,
author = {E. P. Baltsavias},
title = {airborne laser scanner : existing systems and firms and other resources},
journal = jprs,
year = {1999},
volume = {54},
pages = {164-198},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-F/1/a8f1d8cc93dff41cd7de73a587282377},
keyword = {airborne laser scanner , airborne laser scanners (technical specifications), airborne laser scanners (commercial firms)},
abstract = {This article gives an overview of resources on airborne laser scanning (ALS). The main emphasis is on existing systems and firms, especially commercial ones. Through a very time-consuming search and with the help of numerous persons from firms, organisations and other colleagues, a quite complete survey of existing commercial systems, including detailed system parameters, has been compiled. This survey is by far the most complete and up-to-date information available today on commercial ALS. Additional data on contact information, links and, in some cases, a short background is given for firms involved in ALS (manufacturers, service providers, owners). A summary of other non-commercial and research systems, mainly of NASA, and respective links is presented. Finally, some other useful WEB links are given. The developments in ALS have been very rapid the last 1¯2 years. This overview reflects these developments and describes rather completely the current situation, thus, being useful for all persons involved in ALS one way or another.},
}
-
J. Bryan Blair,
David L. Rabine,
and Michelle A. Hofton.
The Laser Vegetation Imaging Sensor: a medium-altitude, digitisation-only, airborne laser altimeter for mapping vegetation and topography.
jprs,
54(2-3):115-122,
1999.
[WWW
] Keyword(s): laser altimetry,
vegetation height,
topography,
lidar.
Abstract: |
The Laser Vegetation Imaging Sensor (LVIS) is an airborne, scanning laser altimeter, designed and developed at NASA's Goddard Space Flight Center (GSFC). LVIS operates at altitudes up to 10 km above ground, and is capable of producing a data swath up to 1000 m wide nominally with 25-m wide footprints. The entire time history of the outgoing and return pulses is digitised, allowing unambiguous determination of range and return pulse structure. Combined with aircraft position and attitude knowledge, this instrument produces topographic maps with dm accuracy and vertical height and structure measurements of vegetation. The laser transmitter is a diode-pumped Nd:YAG oscillator producing 1064 nm, 10 ns, 5 mJ pulses at repetition rates up to 500 Hz. LVIS has recently demonstrated its ability to determine topography (including sub-canopy) and vegetation height and structure on flight missions to various forested regions in the US and Central America. The LVIS system is the airborne simulator for the Vegetation Canopy Lidar (VCL) mission (a NASA Earth remote sensing satellite due for launch in year 2000), providing simulated data sets and a platform for instrument proof-of-concept studies. The topography maps and return waveforms produced by LVIS provide Earth scientists with a unique data set allowing studies of topography, hydrology, and vegetation with unmatched accuracy and coverage. |
@Article{blair99,
author = {J. Bryan Blair and David L. Rabine and Michelle A. Hofton},
title = {The Laser Vegetation Imaging Sensor: a medium-altitude, digitisation-only, airborne laser altimeter for mapping vegetation and topography},
journal = jprs,
year = {1999},
volume = {54},
pages = {115-122},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-7/1/61971a62f8a50b90737f74cb82bdf278},
keyword = {laser altimetry, vegetation height, topography, lidar},
abstract = {The Laser Vegetation Imaging Sensor (LVIS) is an airborne, scanning laser altimeter, designed and developed at NASA's Goddard Space Flight Center (GSFC). LVIS operates at altitudes up to 10 km above ground, and is capable of producing a data swath up to 1000 m wide nominally with 25-m wide footprints. The entire time history of the outgoing and return pulses is digitised, allowing unambiguous determination of range and return pulse structure. Combined with aircraft position and attitude knowledge, this instrument produces topographic maps with dm accuracy and vertical height and structure measurements of vegetation. The laser transmitter is a diode-pumped Nd:YAG oscillator producing 1064 nm, 10 ns, 5 mJ pulses at repetition rates up to 500 Hz. LVIS has recently demonstrated its ability to determine topography (including sub-canopy) and vegetation height and structure on flight missions to various forested regions in the US and Central America. The LVIS system is the airborne simulator for the Vegetation Canopy Lidar (VCL) mission (a NASA Earth remote sensing satellite due for launch in year 2000), providing simulated data sets and a platform for instrument proof-of-concept studies. The topography maps and return waveforms produced by LVIS provide Earth scientists with a unique data set allowing studies of topography, hydrology, and vegetation with unmatched accuracy and coverage.},
}
-
M. Daniel and A. Willsky.
The Modeling and Estimation of Statistically Self-Similar Processes in a Multiresolution Framework.
INFOR,
45(3):955-970,
April 1999.
@article{RefWorks:710,
author={M. Daniel and A. Willsky},
year={1999},
month={Apr},
title={The Modeling and Estimation of Statistically Self-Similar Processes in a Multiresolution Framework},
journal={INFOR},
volume={45},
number={3},
pages={955-970}
}
-
Norbert Haala and Claus Brenner.
Extraction of buildings and trees in urban environments.
jprs,
54(2-3):130-137,
1999.
[WWW
] Keyword(s): virtual city models,
3D modeling,
classification,
building extraction,
tree extraction.
Abstract: |
In this article, two methods for data collection in urban environments are presented. The first method combines multispectral imagery and laser altimeter data in an integrated classification for the extraction of buildings, trees and grass-covered areas. The second approach uses laser data and 2D ground plan information to obtain 3D reconstructions of buildings. |
@Article{haala99,
author = {Norbert Haala and Claus Brenner},
title = {Extraction of buildings and trees in urban environments},
journal = jprs,
year = {1999},
volume = {54},
pages = {130-137},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-9/1/e73e316c20fb85c428c36e42f8f05004},
keyword = {virtual city models, 3D modeling, classification, building extraction, tree extraction},
abstract = {In this article, two methods for data collection in urban environments are presented. The first method combines multispectral imagery and laser altimeter data in an integrated classification for the extraction of buildings, trees and grass-covered areas. The second approach uses laser data and 2D ground plan information to obtain 3D reconstructions of buildings.},
}
-
Jamie Hansen and David Jonas.
AIRBORNE LASER SCANNING OR AERIAL PHOTOGRAMMETRY FOR THE MINE SURVEYOR.
AAM Surveys Inc.,
1999.
Abstract: |
Airborne Laser Scanning (ALS) was first introduced into Australia in 1998 and has since proved its worth as a broad-acre terrain-modelling tool. But is this technology relevant to the spatial data needs required in the Australian mining industry? This paper discusses the pros and cons of the ALS system in comparison with photogrammetry, the current broad-acre data acquisition technique utilised by most mining operations. The findings are that ALS is not going to revolutionise data acquisition in Australian mines, but that it does provide a useful contribution to the mine surveyor's toolkit. To complete the comparison, recent advances in photogrammetry are also discussed. |
@article{hansen99,
author = {Jamie Hansen and David Jonas},
title = {AIRBORNE LASER SCANNING OR AERIAL PHOTOGRAMMETRY FOR THE MINE SURVEYOR},
journal = {AAM Surveys Inc.},
year = 1999,
volume = "",
abstract = {Airborne Laser Scanning (ALS) was first introduced into Australia in 1998 and has since proved its worth as a broad-acre terrain-modelling tool. But is this technology relevant to the spatial data needs required in the Australian mining industry? This paper discusses the pros and cons of the ALS system in comparison with photogrammetry, the current broad-acre data acquisition technique utilised by most mining operations. The findings are that ALS is not going to revolutionise data acquisition in Australian mines, but that it does provide a useful contribution to the mine surveyor's toolkit. To complete the comparison, recent advances in photogrammetry are also discussed.},
pages = {},
}
-
Juha Hyyppä,
Hannu Hyyppä,
Mikko Inkinen,
Marcus Engdahl,
Susan Linko,
and Yi-Hong Zhu.
Accuracy comparison of various remote sensing data sources in the retrieval of forest stand attributes.
fem,
128:109-120,
1999.
Abstract: |
Recent advances in developing new airborne instruments and space-borne missions and in SAR technology, especially in interferometry and coherence estimation, have roused questions: can such new SAR data be utilized in operational forest inventory? What is the accuracy of different satellite data for forest inventory? This paper verifies the explanatory power and information contents of several remote sensing data sources on the retrieval of stem volume, basal area, and mean height, utilizing the following data: Landsat TM, Spot PAN and XS, ERS-1/2 PRI and SLC (coherence estimation), airborne data from imaging spectrometer AISA, radar-derived forest canopy profiles (obtained with HUTSCAT), and aerial photographs. Ground truth data included three different sets ranging from conventional forest inventory data to intensive field checking where one man-day was spent for assessing one stand. Multivariate and neural network methods were applied in data analysis. The results suggested that (1) radar-derived stand profiles obtained with 100 m spacing was the most accurate data source in this comparison and was of equivalent accuracy with conventional forest inventory for mean height and stem volume estimation, (2) aerial photographs (scale 1 : 20,000) gave comparable results with the imaging spectrometer AISA, (3) the satellite images used for the estimation in the decreasing explanation power were Spot XS, Spot PAN, Landsat TM, ERS SAR coherence, JERS SAR intensity images (PRI), and ERS SAR intensity images (PRI). It appears that optical images still include more information for forest inventory than radar images, (4) from all satellite radar methods, the coherence technique seemed to be superior to other methods. |
@Article{hyyppae99,
author = {Juha Hyyppä and Hannu Hyyppä and Mikko Inkinen and Marcus Engdahl and Susan Linko and Yi-Hong Zhu},
title = {Accuracy comparison of various remote sensing data sources in the retrieval of forest stand attributes},
journal = fem,
year = {1999},
volume = {128},
pages = {109-120},
abstract = {Recent advances in developing new airborne instruments and space-borne missions and in SAR technology, especially in interferometry and coherence estimation, have roused questions: can such new SAR data be utilized in operational forest inventory? What is the accuracy of different satellite data for forest inventory? This paper verifies the explanatory power and information contents of several remote sensing data sources on the retrieval of stem volume, basal area, and mean height, utilizing the following data: Landsat TM, Spot PAN and XS, ERS-1/2 PRI and SLC (coherence estimation), airborne data from imaging spectrometer AISA, radar-derived forest canopy profiles (obtained with HUTSCAT), and aerial photographs. Ground truth data included three different sets ranging from conventional forest inventory data to intensive field checking where one man-day was spent for assessing one stand. Multivariate and neural network methods were applied in data analysis. The results suggested that (1) radar-derived stand profiles obtained with 100 m spacing was the most accurate data source in this comparison and was of equivalent accuracy with conventional forest inventory for mean height and stem volume estimation, (2) aerial photographs (scale 1 : 20,000) gave comparable results with the imaging spectrometer AISA, (3) the satellite images used for the estimation in the decreasing explanation power were Spot XS, Spot PAN, Landsat TM, ERS SAR coherence, JERS SAR intensity images (PRI), and ERS SAR intensity images (PRI). It appears that optical images still include more information for forest inventory than radar images, (4) from all satellite radar methods, the coherence technique seemed to be superior to other methods. },
}
-
Jennifer L. Irish and W. Jeff Lillycrop.
Scanning laser mapping of the coastal zone: the SHOALS system.
jprs,
54(2-3):123-129,
1999.
[WWW
] Keyword(s): hydrographic survey,
lidar,
remote sensing,
Saco River,
SHOALS.
Abstract: |
The SHOALS system uses lidar technology to remotely measure bathymetry and topography in the coastal zone. During five years of survey operations, SHOALS has demonstrated airborne lidar bathymetry's benefits to the coastal community by providing a cost-effective tool for comprehensive assessment of coastal projects. This paper discusses the application of lidar technology for water-depth measurement, specifically outlining the SHOALS system and introducing a SHOALS survey from Saco River, ME. |
@Article{irish99,
author = {Jennifer L. Irish and W. Jeff Lillycrop},
title = {Scanning laser mapping of the coastal zone: the SHOALS system},
journal = jprs,
year = {1999},
volume = {54},
pages = {123-129},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-8/1/73ce19413efe236df8fd875694eeb613},
keyword = {hydrographic survey, lidar, remote sensing, Saco River, SHOALS},
abstract = {The SHOALS system uses lidar technology to remotely measure bathymetry and topography in the coastal zone. During five years of survey operations, SHOALS has demonstrated airborne lidar bathymetry's benefits to the coastal community by providing a cost-effective tool for comprehensive assessment of coastal projects. This paper discusses the application of lidar technology for water-depth measurement, specifically outlining the SHOALS system and introducing a SHOALS survey from Saco River, ME.},
}
-
A. K. Johnston,
G. Parker,
and M. Lefsky.
Remote Sensing of Forest Canopy Structure.
Earth and Planetary Studies, Smithsonian Institution,
1999.
Note: Note: http://www.nasm.si.edu/research/ceps/research/johnston/dc/forest.html.
@article{RefWorks:813,
author={A. K. Johnston and G. Parker and M. Lefsky},
year={1999},
title={Remote Sensing of Forest Canopy Structure},
journal={Earth and Planetary Studies, Smithsonian Institution},
note={note: http://www.nasm.si.edu/research/ceps/research/johnston/dc/forest.html}
}
-
Barbara Koch and Hans Friedlaender.
Erste Erfahrungen zum Einsatz von Laserscannerdaten zur Erfassung von vertikalen und horizontalen Strukturen im Wald.
1999.
Abstract: |
Zielsetzung der Untersuchungen ist es zu pr"ufen, in welchem Umfang flugzeuggetragene Laserscannersysteme im Rahmen von Waldinventur und wald"okologischen Untersuchungen eingesetzt werden koennen. Hierbei sollen neue Methoden zur Informationsextraktion und -darstellung entwickelt und bestehende Algorithmen erprobt werden. Im Rahmen der Forstinventur sind insbesondere die automatische Messung von Baumh"ohen f"ur verschiedene Baumarten und die automatische Kronendelinierung von grossem Interesse, um daraus Inventurgroessen, wie Holzvolumen und Stammfl"ache u.a. abzuleiten. Im Hinblick auf die Wald"okosystemforschung und -kartierung ist dar"uber hinaus die Erfassung der Horizontal und Vertikalstrukturen sowie die Entwicklung von Kronenstrukturmodellen von Bedeutung. Neben der Informationsextraktion aus Laserscannerdaten wird im Rahmen des Untersuchungsprojektes eine Verkn"upfung von Laserscannerdaten mit optischen Daten, insbesondere den neuen hochaufl"osenden Daten, wie sie von Ikonos zur Verf"ugung gestellt werden, durchgef"uhrt, um auf der Basis der zus"atzlichen spektralen Information Aussagen zur Baumart und Vitalit"at in die forstlichen Modelle zur Datennutzung einbauen zu k"onnen. Langfristige Zielsetzung ist die Ableitung forstlicher und wald"okologischer Parameter durch Informationsextraktion aus kombinierten multispektralen Daten und Laserscannerdaten. |
@Article{koch,
author = {Barbara Koch and Hans Friedlaender},
title = {Erste Erfahrungen zum Einsatz von Laserscannerdaten zur Erfassung von vertikalen und horizontalen Strukturen im Wald},
journal = {},
year = {1999},
volume = {},
pages = {},
abstract = {Zielsetzung der Untersuchungen ist es zu pr"ufen, in welchem Umfang flugzeuggetragene Laserscannersysteme im Rahmen von Waldinventur und wald"okologischen Untersuchungen eingesetzt werden koennen. Hierbei sollen neue Methoden zur Informationsextraktion und -darstellung entwickelt und bestehende Algorithmen erprobt werden. Im Rahmen der Forstinventur sind insbesondere die automatische Messung von Baumh"ohen f"ur verschiedene Baumarten und die automatische Kronendelinierung von grossem Interesse, um daraus Inventurgroessen, wie Holzvolumen und Stammfl"ache u.a. abzuleiten. Im Hinblick auf die Wald"okosystemforschung und -kartierung ist dar"uber hinaus die Erfassung der Horizontal und Vertikalstrukturen sowie die Entwicklung von Kronenstrukturmodellen von Bedeutung. Neben der Informationsextraktion aus Laserscannerdaten wird im Rahmen des Untersuchungsprojektes eine Verkn"upfung von Laserscannerdaten mit optischen Daten, insbesondere den neuen hochaufl"osenden Daten, wie sie von Ikonos zur Verf"ugung gestellt werden, durchgef"uhrt, um auf der Basis der zus"atzlichen spektralen Information Aussagen zur Baumart und Vitalit"at in die forstlichen Modelle zur Datennutzung einbauen zu k"onnen. Langfristige Zielsetzung ist die Ableitung forstlicher und wald"okologischer Parameter durch Informationsextraktion aus kombinierten multispektralen Daten und Laserscannerdaten.},
}
-
P. Kumar.
A Multiple Scale State-Space Model for Characterizing Subgrid Scale Variability of Near-Surface Soil Moisture.
TGARS,
37(1):182-197,
January 1999.
Note: NOTE: This paper was pointed out my a reviewer of my TGARS 2000 submission. So I cite it in my TGARS 2001 revised paper. It is a straight-forward application of the Willsky method. It assumes the standard linear relationship between observations and the state. It gives a nice discusion on Markovian and blockiness isses.
@article{RefWorks:713,
author={P. Kumar},
year={1999},
month={Jan},
title={A Multiple Scale State-Space Model for Characterizing Subgrid Scale Variability of Near-Surface Soil Moisture},
journal={TGARS},
volume={37},
number={1},
pages={182-197},
note={NOTE: This paper was pointed out my a reviewer of my TGARS 2000 submission. So I cite it in my TGARS 2001 revised paper. It is a straight-forward application of the Willsky method. It assumes the standard linear relationship between observations and the state. It gives a nice discusion on Markovian and blockiness isses.}
}
-
M. A. Lefsky,
W. B. Cohen,
S. A. Acker,
G. G. Parker,
T. A. Spies,
and D. Harding.
LiDAR remote sensing of the canopy structure and biophysical properties of Douglas-fir western hemlock forests.
Remote Sensing of Environment,
70:339-361,
1999.
@article{RefWorks:819,
author={M. A. Lefsky and W. B. Cohen and S. A. Acker and G. G. Parker and T. A. Spies and D. Harding},
year={1999},
title={LiDAR remote sensing of the canopy structure and biophysical properties of Douglas-fir western hemlock forests},
journal={Remote Sensing of Environment},
volume={70},
pages={339-361}
}
-
M. A. Lefsky,
W. B. Cohen,
S. A. Acker,
G. G. Parker,
T. A. Spies,
and D. Harding.
Lidar Remote Sensing of the Canopy Structure and Biophysical Properties of Douglas-Fir Western Hemlock Forests.
rse,
70:339-361,
1999.
[WWW
]
Abstract: |
Scanning lidar remote sensing systems have recently become available for use in ecological applications. Unlike conventional microwave and optical sensors, lidar sensors directly measure the distribution of vegetation material along the vertical axis and can be used to provide three-dimensional, or volumetric, characterizations of vegetation structure. Ecological applications of scanning lidar have hitherto used one-dimensional indices to characterize canopy height. A novel three-dimensional analysis of lidar waveforms was developed to characterize the total volume and spatial organization of vegetation material and empty space within the forest canopy. These aspects of the physical structure of canopies have been infrequently measured, from either field or remote methods. We applied this analysis to 22 plots in Douglas-fir/western hemlock stands on the west slope of the Cascades Range in Oregon. Each plot had coincident lidar data and field measurements of stand structure. We compared results from the novel analysis to two earlier meth-ods of canopy description. Using the indices of canopy structure from all three methods of description as independent variables in a stepwise multiple regression, we were able to make nonasymptotic predictions of biomass and leaf area index (LAI) over a wide range, up to 1200 Mg/ha of biomass and an LAI of 12, with 90 $\%$ and 75 $\%$ of variance explained, respectively. Furthermore, we were able to make accurate estimates of other stand structure attributes, including the mean and standard deviation of diameter at breast height, the number of stems greater than 100 cm in diameter, and independent estimates of the basal area of Douglas-fir and western hemcharacterize lock. These measurements can be directly related to indices of forest stand structural complexity, such as those developed for old-growth forest characterization. Indices of canopy structure developed using the novel, threedimensional analysis accounted for most of the variables used in predictive equations generated by the stepwise multiple regression. |
@Article{lefsky99,
author = {M. A. Lefsky and W. B. Cohen and S. A. Acker and G. G. Parker and T. A. Spies and D. Harding},
title = {Lidar Remote Sensing of the Canopy Structure and Biophysical Properties of Douglas-Fir Western Hemlock Forests},
journal = rse,
year = {1999},
volume = {70},
pages = {339-361},
keyword = {},
url = {http://www.sciencedirect.com/science/article/B6V6V-3Y80MCP-9/1/3c5204f0b50f8e467ab0ff75c0ba4540},
abstract = {Scanning lidar remote sensing systems have recently become available for use in ecological applications. Unlike conventional microwave and optical sensors, lidar sensors directly measure the distribution of vegetation material along the vertical axis and can be used to provide three-dimensional, or volumetric, characterizations of vegetation structure. Ecological applications of scanning lidar have hitherto used one-dimensional indices to characterize canopy height. A novel three-dimensional analysis of lidar waveforms was developed to characterize the total volume and spatial organization of vegetation material and empty space within the forest canopy. These aspects of the physical structure of canopies have been infrequently measured, from either field or remote methods. We applied this analysis to 22 plots in Douglas-fir/western hemlock stands on the west slope of the Cascades Range in Oregon. Each plot had coincident lidar data and field measurements of stand structure. We compared results from the novel analysis to two earlier meth-ods of canopy description. Using the indices of canopy structure from all three methods of description as independent variables in a stepwise multiple regression, we were able to make nonasymptotic predictions of biomass and leaf area index (LAI) over a wide range, up to 1200 Mg/ha of biomass and an LAI of 12, with 90 $\%$ and 75 $\%$ of variance explained, respectively. Furthermore, we were able to make accurate estimates of other stand structure attributes, including the mean and standard deviation of diameter at breast height, the number of stems greater than 100 cm in diameter, and independent estimates of the basal area of Douglas-fir and western hemcharacterize lock. These measurements can be directly related to indices of forest stand structural complexity, such as those developed for old-growth forest characterization. Indices of canopy structure developed using the novel, threedimensional analysis accounted for most of the variables used in predictive equations generated by the stepwise multiple regression.},
}
-
M. A. Lefsky,
D. Harding,
W. B. Cohen,
G. Parker,
and H. H. Shugart.
Surface Lidar Remote Sensing of Basal Area and Biomass in Deciduous Forests of Eastern Maryland.
Remote Sensing of Environment,
67(1):83-98,
1999.
@article{RefWorks:818,
author={M. A. Lefsky and D. Harding and W. B. Cohen and G. Parker and H. H. Shugart},
year={1999},
title={Surface Lidar Remote Sensing of Basal Area and Biomass in Deciduous Forests of Eastern Maryland},
journal={Remote Sensing of Environment},
volume={67},
number={1},
pages={83-98}
}
-
Michael A. Lefsky,
D. Harding,
W. B. Cohen,
G. Parker,
and and H. H. Shugart.
Surface Lidar Remote Sensing of Basal Area and Biomass in Deciduous Forests of Eastern Maryland, USA.
rse,
67:83-98,
1999.
[WWW
] Keyword(s): Remote sensing,
Forestry,
Optical radar,
Biomass,
Data acquisition,
Regression analysis,
airborne laser scanner,
Quadratic mean canopy height,
Chronosequence data set.
Abstract: |
A method of predicting two forest stand structure attributes, basal area and aboveground biomass, from measurements of forest vertical structure was developed and tested using field and remotely sensed canopy structure measurements. Coincident estimates of the vertical distribution of canopy surface area (the canopy height profile), and field-measured stand structure attributes were acquired for two data sets. The chronosequence data set consists of 48 plots in stands distributed within 25 miles of Annapolis, MD, with canopy height profiles measured in the field using the optical-quadrat method. The stem-map data set consists of 75 plots subsetted from a single 32 ha stem-mapped stand, with measurements of their canopy height profiles made using the SLICER (Scanning Lidar Imager of Canopies by Echo Recovery) instrument, an airborne surface lidar system. Four height indices, maximum, median, mean, and quadratic mean canopy height (QMCH) were calculated from the canopy height profiles. Regressions between the indices and stand basal area and biomass were developed using the chronosequence data set. The regression equations developed from the chronosequence data set were then applied to height indices calculated from the remotely sensed canopy height profiles from the stem map data set, and the ability of the regression equations to predict the stem map plotÕs stand structure attributes was then evaluated. The QMCH was found to explain the most variance in the chronosequence data setÕs stand structure attributes, and to most accurately predict the values of the same attributes in the stem map data set. For the chronosequence data set, the QMCH predicted 70 $\%$ of variance in stand basal area, and 80 $\%$ of variance in aboveground biomass, and remained nonasymptotic with basal areas up to 50 m2/ha, and aboveground biomass values up to 450 Mg/ha. When applied to the stem-map data set, the regression equations resulted in basal areas that were, on average, underestimated by 2.1 m2 ha21, and biomass values were underestimated by 16 Mg ha21, and explained 37 $\%$ and 33 $\%$ of variance, respectively. Differences in the magnitude of the coefficients of determination were due to the wider range of stand conditions found in the chronosequence data set; the standard deviation of residual values were lower in the stem map data set than on the chronosequence data sets. Stepwise multiple regression was performed to predict the two stand structure attributes using the canopy height profile data directly as independent variables, but they did not improve the accuracy of the estimates over the height index approach. |
@Article{lefsky99b,
author = {Michael A. Lefsky and D. Harding and W. B. Cohen and G. Parker and and H. H. Shugart},
title = {Surface Lidar Remote Sensing of Basal Area and Biomass in Deciduous Forests of Eastern Maryland, USA},
journal = rse,
year = {1999},
volume = {67},
pages = {83-98},
keywords = {Remote sensing, Forestry, Optical radar, Biomass, Data acquisition, Regression analysis, airborne laser scanner, Quadratic mean canopy height, Chronosequence data set},
url = {http://www.sciencedirect.com/science/article/B6V6V-3V92YV3-6/1/a8376b26a910bc48dcdea9adb1fa6bfa},
abstract = {A method of predicting two forest stand structure attributes, basal area and aboveground biomass, from measurements of forest vertical structure was developed and tested using field and remotely sensed canopy structure measurements. Coincident estimates of the vertical distribution of canopy surface area (the canopy height profile), and field-measured stand structure attributes were acquired for two data sets. The chronosequence data set consists of 48 plots in stands distributed within 25 miles of Annapolis, MD, with canopy height profiles measured in the field using the optical-quadrat method. The stem-map data set consists of 75 plots subsetted from a single 32 ha stem-mapped stand, with measurements of their canopy height profiles made using the SLICER (Scanning Lidar Imager of Canopies by Echo Recovery) instrument, an airborne surface lidar system. Four height indices, maximum, median, mean, and quadratic mean canopy height (QMCH) were calculated from the canopy height profiles. Regressions between the indices and stand basal area and biomass were developed using the chronosequence data set. The regression equations developed from the chronosequence data set were then applied to height indices calculated from the remotely sensed canopy height profiles from the stem map data set, and the ability of the regression equations to predict the stem map plotÕs stand structure attributes was then evaluated. The QMCH was found to explain the most variance in the chronosequence data setÕs stand structure attributes, and to most accurately predict the values of the same attributes in the stem map data set. For the chronosequence data set, the QMCH predicted 70 $\%$ of variance in stand basal area, and 80 $\%$ of variance in aboveground biomass, and remained nonasymptotic with basal areas up to 50 m2/ha, and aboveground biomass values up to 450 Mg/ha. When applied to the stem-map data set, the regression equations resulted in basal areas that were, on average, underestimated by 2.1 m2 ha21, and biomass values were underestimated by 16 Mg ha21, and explained 37 $\%$ and 33 $\%$ of variance, respectively. Differences in the magnitude of the coefficients of determination were due to the wider range of stand conditions found in the chronosequence data set; the standard deviation of residual values were lower in the stem map data set than on the chronosequence data sets. Stepwise multiple regression was performed to predict the two stand structure attributes using the canopy height profile data directly as independent variables, but they did not improve the accuracy of the estimates over the height index approach.},
}
-
Hans-Gerd Maas.
THE POTENTIAL OF HEIGHT TEXTURE MEASURES FOR THE SEGMENTATION OF AIRBORNE LASERSCANNER DATA.
Fourth International Airborne Remote Sensing Conference and Exhibition,
21st Canadian Symposium on Remote Sensing:Ottawa, Ontario, Canada,
1999.
Abstract: |
Airborne laserscanning is being used for an increasing number of mapping and GIS data acquisition tasks. Besides the original purpose of digital terrain model generation, new applications arise in the automatic detection and modeling of objects such as buildings or vegetation for the generation of 3-D city models. A crucial prerequisite for the automatic extraction of objects on the Earth's surface from las-erscanner height data is the segmentation of datasets. Besides the height itself, height texture defined by local variations of the height is a significant feature of objects to be rec-ognized. The paper shows the potential of the analysis of height texture for the automatic segmentation of dense laserscanner datasets and the detection of objects in the segmented data. Based on the definition and computation of a number of texture measures used as bands in a classification approach, objects like buildings, single trees, ground vegetation and roads can be recognized. The technique was applied to a FLI-MAP laserscanner dataset with an average point density of more than five points per squaremeter, acquired over a village in The Netherlands. In a maximum likelihood classification based on the absolute height and several texture measures derived from it, a classification accuracy of 98\% could be achieved. Based on the result of the segmentation, all buildings of the scene and most single trees could be automatically detected. |
@Article{maas99,
author = {Hans-Gerd Maas},
title = {THE POTENTIAL OF HEIGHT TEXTURE MEASURES FOR THE SEGMENTATION OF AIRBORNE LASERSCANNER DATA},
journal = {Fourth International Airborne Remote Sensing Conference and Exhibition},
year = {1999},
volume = {21st Canadian Symposium on Remote Sensing},
pages = {Ottawa, Ontario, Canada},
number = {},
url = {},
keyword = {},
abstract = {Airborne laserscanning is being used for an increasing number of mapping and GIS data acquisition tasks. Besides the original purpose of digital terrain model generation, new applications arise in the automatic detection and modeling of objects such as buildings or vegetation for the generation of 3-D city models. A crucial prerequisite for the automatic extraction of objects on the Earth's surface from las-erscanner height data is the segmentation of datasets. Besides the height itself, height texture defined by local variations of the height is a significant feature of objects to be rec-ognized. The paper shows the potential of the analysis of height texture for the automatic segmentation of dense laserscanner datasets and the detection of objects in the segmented data. Based on the definition and computation of a number of texture measures used as bands in a classification approach, objects like buildings, single trees, ground vegetation and roads can be recognized. The technique was applied to a FLI-MAP laserscanner dataset with an average point density of more than five points per squaremeter, acquired over a village in The Netherlands. In a maximum likelihood classification based on the absolute height and several texture measures derived from it, a classification accuracy of 98\% could be achieved. Based on the result of the segmentation, all buildings of the scene and most single trees could be automatically detected.},
}
-
Hans-Gerd Maas and George Vosselman.
Two algorithms for extracting building models from raw laser altimetry data.
jprs,
54(2-3):153-163,
1999.
[WWW
] Keyword(s): airborne laser scanner,
building modelling,
invariant moments,
geometric reasoning.
Abstract: |
Two new techniques for the determination of building models from laser altimetry data are presented. Both techniques work on the original laser scanner data points without the requirement of an interpolation to a regular grid. Available ground plan information may be used, but is not required. Closed solutions for the determination of the parameters of a standard gable roof type building model based on invariant moments of 2 1/2-D point clouds are shown. In addition, the analysis of deviations between point cloud and model does allow for modelling asymmetries such as dorms on a gable roof. By intersecting planar faces nonparametric buildings with more complex roof types can also be modelled. The techniques were applied to a FLI-MAP laser scanner dataset covering an area of 500×250 m2 with a density of more than 5 points/m2. Within this region, all but one building could be modelled. An analysis of the variance of the parameters within a group of buildings indicates a precision in the range of 0.1¯0.2 m. |
@Article{maas99,
author = {Hans-Gerd Maas and George Vosselman},
title = {Two algorithms for extracting building models from raw laser altimetry data},
journal = jprs,
year = {1999},
volume = {54},
pages = {153-163},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-D/1/2ab469c94d1f33bc54ae6f9cb55d5c99},
keyword = {airborne laser scanner , building modelling, invariant moments, geometric reasoning},
abstract = {Two new techniques for the determination of building models from laser altimetry data are presented. Both techniques work on the original laser scanner data points without the requirement of an interpolation to a regular grid. Available ground plan information may be used, but is not required. Closed solutions for the determination of the parameters of a standard gable roof type building model based on invariant moments of 2 1/2-D point clouds are shown. In addition, the analysis of deviations between point cloud and model does allow for modelling asymmetries such as dorms on a gable roof. By intersecting planar faces nonparametric buildings with more complex roof types can also be modelled. The techniques were applied to a FLI-MAP laser scanner dataset covering an area of 500×250 m2 with a density of more than 5 points/m2. Within this region, all but one building could be modelled. An analysis of the variance of the parameters within a group of buildings indicates a precision in the range of 0.1¯0.2 m.},
}
-
S. Magnussen,
F. Gougeon,
D. Leckie,
and M. Wulder.
Predicting tree heights from a combination of LIDAR canopy heights and digital stem counts.
Remote Sensing and Forest Monitoring, Rogow, Poland,
Conference Proceedings,
1999.
[WWW
]
Abstract: |
Tree heights can be derived from LIDAR (Light Detection And Ranging) data of canopy heights when estimates of the expected number ( hit N ) of 'tree top' hits exists. Then, the topmost hit N canopy heights can be considered as proxies of tree height. This simple concept is demonstrated in a thinning trial with 39-year-old Douglas-fir. The probability of a LIDAR pulse hitting a tree top is governed by the number and size of 'tree tops'. Counts of trees with a sunlit crown were derived from Compact Airborne Spectrographic Imager images with 55 x 55 cm pixels. Pairing this count with an assumed 'tree top' size of 3 pixels suggested an average of 6 'tree top' hits in a 400 m2 plot. Extreme value distributions fitted to expected 'tree-top' hits generated various statistics of predicted dominant and codominant tree heights. Our approach lowered the average discrepancy between mean canopy and Lorey's mean tree height from 20 $\%$ to a non-significant 3 $\%$ (P=0.09). Ground-based tree-counts improved the results slightly. |
@Article{magnussen,
author = {S. Magnussen and F. Gougeon and D. Leckie and M. Wulder},
title = {Predicting tree heights from a combination of LIDAR canopy heights and digital stem counts},
journal = {Remote Sensing and Forest Monitoring, Rogow, Poland},
year = {1999},
volume = {Conference Proceedings},
pages = {},
url = {http://rogow99.sggw.waw.pl/},
abstract = {Tree heights can be derived from LIDAR (Light Detection And Ranging) data of canopy heights when estimates of the expected number ( hit N ) of 'tree top' hits exists. Then, the topmost hit N canopy heights can be considered as proxies of tree height. This simple concept is demonstrated in a thinning trial with 39-year-old Douglas-fir. The probability of a LIDAR pulse hitting a tree top is governed by the number and size of 'tree tops'. Counts of trees with a sunlit crown were derived from Compact Airborne Spectrographic Imager images with 55 x 55 cm pixels. Pairing this count with an assumed 'tree top' size of 3 pixels suggested an average of 6 'tree top' hits in a 400 m2 plot. Extreme value distributions fitted to expected 'tree-top' hits generated various statistics of predicted dominant and codominant tree heights. Our approach lowered the average discrepancy between mean canopy and Lorey's mean tree height from 20 $\%$ to a non-significant 3 $\%$ (P=0.09). Ground-based tree-counts improved the results slightly.},
}
-
Joseph E. Means,
Steven A. Acker,
David J. Harding,
J. Bryan Blair,
Michael A. Lefsky,
Warren B. Cohen,
Mark E. Harmon,
and W. Arthur McKee.
Use of Large-Footprint Scanning Airborne Lidar To Estimate Forest Stand Characteristics in the Western Cascades of Oregon.
rse,
67:298-308,
1999.
[WWW
]
Abstract: |
A scanning lidar, a relatively new type of sensor which explicitly measures canopy height, was used to measure structure of conifer forests in the Pacific Northwest. SLICER (Scanning Lidar Imager of Canopies by Echo Recovery), an airborne pulsed laser developed by NASA which scans a swath of five 10-m diameter footprints along the aircraftÕs flightpath, captures the power of the reflected laser pulse as a function of height from the top of the canopy to the ground. Ground measurements of forest stand structure were collected on 26 plots with coincident SLICER data. Height, basal area, total biomass, and leaf biomass as estimated from field data could be predicted from SLICER-derived metrics with r2 values of 0.95, 0.96, 0.96, and 0.84, respectively. These relationships were strong up to a height of 52 m, basal area of 132 m2/ha and total biomass of 1300 Mg/ha. In light of these strong relationships, large-footprint, airborne scanning lidar shows promise for characterizing stand structure for management and research purposes. |
@Article{means,
author = {Joseph E. Means and Steven A. Acker and David J. Harding and J. Bryan Blair and Michael A. Lefsky and Warren B. Cohen and Mark E. Harmon and W. Arthur McKee},
title = {Use of Large-Footprint Scanning Airborne Lidar To Estimate Forest Stand Characteristics in the Western Cascades of Oregon},
journal = rse,
year = {1999},
volume = {67},
pages = {298-308},
url = {http://www.sciencedirect.com/science/article/B6V6V-3VR5HX5-4/1/fe202e3c86bb39a7671212b791f86cb9},
abstract = {A scanning lidar, a relatively new type of sensor which explicitly measures canopy height, was used to measure structure of conifer forests in the Pacific Northwest. SLICER (Scanning Lidar Imager of Canopies by Echo Recovery), an airborne pulsed laser developed by NASA which scans a swath of five 10-m diameter footprints along the aircraftÕs flightpath, captures the power of the reflected laser pulse as a function of height from the top of the canopy to the ground. Ground measurements of forest stand structure were collected on 26 plots with coincident SLICER data. Height, basal area, total biomass, and leaf biomass as estimated from field data could be predicted from SLICER-derived metrics with r2 values of 0.95, 0.96, 0.96, and 0.84, respectively. These relationships were strong up to a height of 52 m, basal area of 132 m2/ha and total biomass of 1300 Mg/ha. In light of these strong relationships, large-footprint, airborne scanning lidar shows promise for characterizing stand structure for management and research purposes.},
}
-
J. E. Means,
S. A. Acker,
D. J. Harding,
J. B. Blair,
M. A. Lefsky,
W. B. Cohen,
M. E. Harmon,
and W. A. McKee.
Use of large-footprint scanning airborne LiDAR to estimate forest stand characteristics in the western cascades of Oregon.
Remote Sensing of Environment,
67:298-308,
1999.
@article{RefWorks:826,
author={J. E. Means and S. A. Acker and D. J. Harding and J. B. Blair and M. A. Lefsky and W. B. Cohen and M. E. Harmon and W. A. McKee},
year={1999},
title={Use of large-footprint scanning airborne LiDAR to estimate forest stand characteristics in the western cascades of Oregon},
journal={Remote Sensing of Environment},
volume={67},
pages={298-308}
}
-
Hiroshi Murakami,
Katsuto Nakagawa,
Hiroyuki Hasegawa,
Taku Shibata,
and Eiji Iwanami.
Change detection of buildings using an airborne laser scanner.
jprs,
54(2-3):148-152,
1999.
[WWW
] Keyword(s): change detection,
airborne laser scanner,
building,
digital surface model.
Abstract: |
This study employed an airborne laser scanner to detect changes of buildings by acquiring a digital surface model (DSM) data of urban areas. Simple comparison between DSM data sets acquired at different occasions successfully detected building changes without omission errors. A CCD array image simultaneously acquired with the DSM data was also automatically orthorectified with the DSM data and indicated to help revise the building database efficiently. |
@Article{murakami99,
author = {Hiroshi Murakami and Katsuto Nakagawa and Hiroyuki Hasegawa and Taku Shibata and Eiji Iwanami},
title = {Change detection of buildings using an airborne laser scanner},
journal = jprs,
year = {1999},
volume = {54},
pages = {148-152},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-C/1/a06a7e0aaa331bd904b863fedea49aec},
keyword = {change detection, airborne laser scanner, building, digital surface model},
abstract = {This study employed an airborne laser scanner to detect changes of buildings by acquiring a digital surface model (DSM) data of urban areas. Simple comparison between DSM data sets acquired at different occasions successfully detected building changes without omission errors. A CCD array image simultaneously acquired with the DSM data was also automatically orthorectified with the DSM data and indicated to help revise the building database efficiently.},
}
-
L. M. Gomes Pereira and R. J. Wicherson.
Suitability of laser data for deriving geographical information A case study in the context of management of fluvial zones.
jprs,
54(2-3):105-114,
1999.
[WWW
] Keyword(s): airborne laser scanner,
river management,
photogrammetry,
DTM.
Abstract: |
In the Netherlands, around 40 $\%$ of the territory is below sea level. Rivers that flow through this land have to be constantly monitored to avoid flooding. To this end, terrain information is needed. At present, the relief information is acquired by means of photogrammetry, which makes the information expensive. Furthermore, it is estimated that at least 4 years are needed to collect the relief information of all river zones. A cheaper and faster alternative appears to be the use of laser measurements acquired from an aircraft. Thus, it is of great importance to determine if the user requirements, concerning information needed and related quality, can be fulfilled by high-density laser measurements. In this article, we assess the feasibility of using laser data to help generate a hydrodynamic model. This is needed to determine the effect of high water levels and of earthworks, such as removal of sand in river areas. The conclusion of this study is that as far as the test area is concerned, which appears to be a good representative of the fluvial regions in the Netherlands, the laser data allow one to recover the relief information needed for river management with the desired quality. |
@Article{pereira99,
author = {L. M. Gomes Pereira and R. J. Wicherson},
title = {Suitability of laser data for deriving geographical information A case study in the context of management of fluvial zones},
journal = jprs,
year = {1999},
volume = {54},
pages = {105-114},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-6/1/5815dbf0a1b1bd288ee8777f11bd52a4},
keyword = {airborne laser scanner, river management, photogrammetry, DTM},
abstract = {In the Netherlands, around 40 $\%$ of the territory is below sea level. Rivers that flow through this land have to be constantly monitored to avoid flooding. To this end, terrain information is needed. At present, the relief information is acquired by means of photogrammetry, which makes the information expensive. Furthermore, it is estimated that at least 4 years are needed to collect the relief information of all river zones. A cheaper and faster alternative appears to be the use of laser measurements acquired from an aircraft. Thus, it is of great importance to determine if the user requirements, concerning information needed and related quality, can be fulfilled by high-density laser measurements. In this article, we assess the feasibility of using laser data to help generate a hydrodynamic model. This is needed to determine the effect of high water levels and of earthworks, such as removal of sand in river areas. The conclusion of this study is that as far as the test area is concerned, which appears to be a good representative of the fluvial regions in the Netherlands, the laser data allow one to recover the relief information needed for river management with the desired quality.},
}
-
Bettina Petzold,
Peter Reiss,
and Wolfgang Stössel.
Laser scanning - surveying and mapping agencies are using a new technique for the derivation of digital terrain models.
jprs,
54(2-3):95-104,
1999.
[WWW
] Keyword(s): airborne laser scanner,
digital terrain model,
mapping agencies,
DTM editing.
Abstract: |
A user group of the Surveying and Mapping Agencies (SMA) of the Federal States of Germany tested several datasets for the derivation of high-quality Digital Terrain Models (DTM) which were collected by laser scanning. Since the results were very promising, a standard procedure for verification and handling of the data was proposed. Because the ground points that are delivered by the contractor are the result of an automated filtering process, final editing is necessary to correct remaining misclassifications. This can be carried out using photogrammetric stereo models or through comparison of the results with large scale topographic maps. Both approaches lead to a high-quality DTM with much shorter production time and less costs as compared to the photogrammetric methods used up to now. |
@Article{petzold99,
author = {Bettina Petzold and Peter Reiss and Wolfgang Stössel},
title = {Laser scanning - surveying and mapping agencies are using a new technique for the derivation of digital terrain models},
journal = jprs,
year = {1999},
volume = {54},
pages = {95-104},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-5/1/f8888bbce31e993c744e4be680abbe56},
keyword = {airborne laser scanner, digital terrain model, mapping agencies, DTM editing},
abstract = {A user group of the Surveying and Mapping Agencies (SMA) of the Federal States of Germany tested several datasets for the derivation of high-quality Digital Terrain Models (DTM) which were collected by laser scanning. Since the results were very promising, a standard procedure for verification and handling of the data was proposed. Because the ground points that are delivered by the contractor are the result of an automated filtering process, final editing is necessary to correct remaining misclassifications. This can be carried out using photogrammetric stereo models or through comparison of the results with large scale topographic maps. Both approaches lead to a high-quality DTM with much shorter production time and less costs as compared to the photogrammetric methods used up to now.},
}
-
Norbert Pfeifer,
Karl Kraus,
and Andre Köstli.
Restitution of airborne laser scanner data in wooded regions.
GIS Geo-Information-Systems, Journal for Spatial Information and Decision Making,
12:18-21,
1999.
Keyword(s): airborne laser scanner.
Abstract: |
Data from air-borne laser scanners provide the chance of accurate digital terrain modelling in forested areas. As a considerable portion of the laser rays is reflected before reaching the ground, a filtering technique sensible for many positive outliers is needed. Linear prediction extended with iterative robust estimation is a promising method for these requirements. In this paper we present the experiences with this algorithm, its implementation and examples. |
@Article{pfeifer99,
author = {Norbert Pfeifer and Karl Kraus and Andre Köstli },
title = {Restitution of airborne laser scanner data in wooded regions},
journal = {GIS Geo-Information-Systems, Journal for Spatial Information and Decision Making},
year = {1999},
volume = {12},
pages = {18-21},
number = {},
url = {},
keyword = {airborne laser scanner},
abstract = {Data from air-borne laser scanners provide the chance of accurate digital terrain modelling in forested areas. As a considerable portion of the laser rays is reflected before reaching the ground, a filtering technique sensible for many positive outliers is needed. Linear prediction extended with iterative robust estimation is a promising method for these requirements. In this paper we present the experiences with this algorithm, its implementation and examples.},
}
-
R. N. Treuhaft and S. R. Cloude.
The Structure of Oriented Vegetation From Polarimetric Interferometry.
TGARS,
37(5):2620-2624,
September 1999.
Note: NOTE: Good description of the *potential* of PINSAR. (1) can get better estimates of vegetation height and surface heights with a single baseline than INSAR can with two baselines because it accounts for orientation of vegetation.
@article{RefWorks:696,
author={R. N. Treuhaft and S. R. Cloude},
year={1999},
month={Sep},
title={The Structure of Oriented Vegetation From Polarimetric Interferometry},
journal={TGARS},
volume={37},
number={5},
pages={2620-2624},
note={NOTE: Good description of the *potential* of PINSAR. (1) can get better estimates of vegetation height and surface heights with a single baseline than INSAR can with two baselines because it accounts for orientation of vegetation.}
}
-
Aloysius Wehr and Uwe Lohr.
Airborne laser scanning - an introduction and overview.
jprs,
54(2-3):68-82,
1999.
[WWW
] Keyword(s): airborne laser scanner,
pulse lasers,
CW-lasers,
laser ranging resolution and precision,
laser scanning methods,
position and orientation systems,
airborne laser scanning (data processing chain).
Abstract: |
This tutorial paper gives an introduction and overview of various topics related to airborne laser scanning (ALS) as used to measure range to and reflectance of objects on the earth surface. After a short introduction, the basic principles of laser, the two main classes, i.e., pulse and continuous-wave lasers, and relations with respect to time-of-flight, range, resolution, and precision are presented. The main laser components and the role of the laser wavelength, including eye safety considerations, are explained. Different scanning mechanisms and the integration of laser with GPS and INS for position and orientation determination are presented. The data processing chain for producing digital terrain and surface models is outlined. Finally, a short overview of applications is given. |
@Article{wehr99,
author = {Aloysius Wehr and Uwe Lohr},
title = {Airborne laser scanning - an introduction and overview},
journal = jprs,
year = {1999},
volume = {54},
pages = {68-82},
number = {2-3},
url = {http://www.sciencedirect.com/science/article/B6VF4-3WY9SWX-3/1/102354999548d9b1847f1d66ab32fca3},
keyword = {airborne laser scanner, pulse lasers, CW-lasers, laser ranging resolution and precision, laser scanning methods, position and orientation systems, airborne laser scanning (data processing chain)},
abstract = {This tutorial paper gives an introduction and overview of various topics related to airborne laser scanning (ALS) as used to measure range to and reflectance of objects on the earth surface. After a short introduction, the basic principles of laser, the two main classes, i.e., pulse and continuous-wave lasers, and relations with respect to time-of-flight, range, resolution, and precision are presented. The main laser components and the role of the laser wavelength, including eye safety considerations, are explained. Different scanning mechanisms and the integration of laser with GPS and INS for position and orientation determination are presented. The data processing chain for producing digital terrain and surface models is outlined. Finally, a short overview of applications is given.},
}