Henrik Haggren - Academia.edu (original) (raw)
Papers by Henrik Haggren
Proceedings of SPIE, Oct 6, 1994
ABSTRACT
Integration of airborne laser scanning (ALS) point clouds and aerial images has a great potential... more Integration of airborne laser scanning (ALS) point clouds and aerial images has a great potential for accurate and robust 3D modeling and recognition of objects in our environment. The integration requires, however, an accurate registration of data sources, which cannot be yet achieved by direct georeferencing using both the GPS and IMU. This research paper presents a method for registering aerial images with ALS data and for evaluating the accuracy of existing registration. An aerial image is included into a multi-scale image block, in which relative orientations of terrestrial close range images and aerial images are then known from the bundle block adjustment. Close range images provide more detailed view of possible tie features and also a new perspective compared to aerial images. For the actual registration of ALS data and image block, one or more images of the block can be chosen. Selected images can include only close range images or both close range images and aerial images. For the registration, the interactive orientation method was used. When selected images are registered with ALS data, the exterior orientations of all other images of the block can be calculated from the known relative orientations. Accuracies of interactive orientations were examined using the reference ALS point cloud that was transformed to the known geodetically determined coordinate system. The coordinate transformation was solved by applying the iterative closest point (ICP) method between the ALS data and the photogrammetrically derived 3D model, the absolute orientation of which was known. Before making experiments of interactive registration, the absolute orientation of the image block was changed in order to get incorrect initial orientation. The final results of interactive orientations were compared with the original orientation information from the bundle block adjustment. The comparison indicated that including an aerial image with a terrestrial image block, the registration of ALS data and aerial images can be improved or verified. The accuracy of the interactive registration was depended on selected images that were used in registration. The maximum differences between original and interactively solved locations of the aerial image varied between 2.3 and 9 cm.
Proceedings of SPIE, Jul 16, 1986
ABSTRACT
Proceedings of SPIE, Mar 1, 1992
ABSTRACT
Proceedings of SPIE, Dec 17, 1993
ABSTRACT
Proceedings of SPIE, Jan 17, 2005
Spherical images are linear images, which are exact in central projection. They are explicitly de... more Spherical images are linear images, which are exact in central projection. They are explicitly determined by the projection center. A general application of spherical imaging is hemispheric visualization of space. We aim to apply spherical imaging at full-scale stereoscopy with projection of spherical images in scale of 1:1. In case of full-scale stereoscopy, the stereoscopic plasticity will have a value of 1 and the base is typically short. Natural viewing would equal to base lengths of human eyes, i.e. to 65 mm. We present in the paper also the Stereodrome, which is a physical realization of full-scale stereo viewing. Originally we have motivated us for building the Stereodrome by the fact that it is the only means to really see the behavior of 3D point clouds in details.
Proceedings of SPIE, Jul 7, 1997
ABSTRACT
Extracting forest variables from airborne laser scanner has less than 10 years of history. During... more Extracting forest variables from airborne laser scanner has less than 10 years of history. During that time, however, a new area in the field of forest studies has emerged. This paper describes existing algorithms and methods of airborne laser scanning that are used for forest measurements. The methods are divided into the following categories: 1) extraction of DTM (digital terrain model), 2) extraction of canopy height, 3) extraction of statistical variables from laser data, 4) extraction of individual tree information using image processing techniques, 5) integrating aerial image data with laser scanner, 6) use of intensity and waveform information, and 7) use of change detection methods.
The economic recession has hit especially hard the residential building sector in the EU region, ... more The economic recession has hit especially hard the residential building sector in the EU region, e.g., the number of the housing completions has decreased -49% and the total residential output has been squeezed down by -24% between 2007 and 2014 (Euroconstruct, 2015). In turn, the aim of our paper is to suggest a set of radical, novel programmes for developing the national residential building sectors within EU member countries up to 2025. We have applied the framework of strategic niche management (SNM) to the diagnoses of the current portfolios of the innovation, R&D programs in our two member country contexts. In the case of the Northern Finland, the prime example is Hiukkavaara, the largest district to be built in the City of Oulu. Homes will be constructed for 20,000 new residents. Hiukkavaara is a model for climate-conscious design in the northern hemisphere. Energy and materials are conserved, nature is valued and human beings adapt to their environment. One sub-programme involves Future Buildings and Renewable Energy Project. In the case of the Netherlands, the prime example is Energiesprong (Energy Leap), i.e., the innovation programme commissioned by the Dutch Ministry of the Interior. The aim is to make buildings energy-neutral and boost large-scale initiatives. The sub-programmes are targeting homes owned by housing associations, privately owned homes, office buildings, shops and care institutions. This programme is about ensuring new supply by encouraging companies to package a variety of technical sub-solutions, full services and financing options as well as about asking clients to put out tenders and ask for quotes in novel ways, with the government making changes to the rules and the regulations. Experiences on which the Dutch case in this paper focuses are sub-programmes for residential buildings which includes Rapids, All Lights on Green and Our Home Deserves It. Based on the emerging Finnish and Dutch evidence, we are suggesting key elements to be incorporated into future national residential programmes within EU member countries on: (1) radical direction with balanced stakeholder groups, trustworthy advocates, contextual goal-setting and barriers management, (2) radical networking with entrepreneurial roles and causal links, novel expertise, transparent choices and digital platforms and (3) radical learning processes to arrive at better informed markets on user preferences, co-innovating, new rules and regulations, higher performance/price ratios, higher quality, new roles and responsibilities assignments.
Proceedings of SPIE, Oct 6, 1994
ABSTRACT
Integration of airborne laser scanning (ALS) point clouds and aerial images has a great potential... more Integration of airborne laser scanning (ALS) point clouds and aerial images has a great potential for accurate and robust 3D modeling and recognition of objects in our environment. The integration requires, however, an accurate registration of data sources, which cannot be yet achieved by direct georeferencing using both the GPS and IMU. This research paper presents a method for registering aerial images with ALS data and for evaluating the accuracy of existing registration. An aerial image is included into a multi-scale image block, in which relative orientations of terrestrial close range images and aerial images are then known from the bundle block adjustment. Close range images provide more detailed view of possible tie features and also a new perspective compared to aerial images. For the actual registration of ALS data and image block, one or more images of the block can be chosen. Selected images can include only close range images or both close range images and aerial images. For the registration, the interactive orientation method was used. When selected images are registered with ALS data, the exterior orientations of all other images of the block can be calculated from the known relative orientations. Accuracies of interactive orientations were examined using the reference ALS point cloud that was transformed to the known geodetically determined coordinate system. The coordinate transformation was solved by applying the iterative closest point (ICP) method between the ALS data and the photogrammetrically derived 3D model, the absolute orientation of which was known. Before making experiments of interactive registration, the absolute orientation of the image block was changed in order to get incorrect initial orientation. The final results of interactive orientations were compared with the original orientation information from the bundle block adjustment. The comparison indicated that including an aerial image with a terrestrial image block, the registration of ALS data and aerial images can be improved or verified. The accuracy of the interactive registration was depended on selected images that were used in registration. The maximum differences between original and interactively solved locations of the aerial image varied between 2.3 and 9 cm.
Proceedings of SPIE, Jul 16, 1986
ABSTRACT
Proceedings of SPIE, Mar 1, 1992
ABSTRACT
Proceedings of SPIE, Dec 17, 1993
ABSTRACT
Proceedings of SPIE, Jan 17, 2005
Spherical images are linear images, which are exact in central projection. They are explicitly de... more Spherical images are linear images, which are exact in central projection. They are explicitly determined by the projection center. A general application of spherical imaging is hemispheric visualization of space. We aim to apply spherical imaging at full-scale stereoscopy with projection of spherical images in scale of 1:1. In case of full-scale stereoscopy, the stereoscopic plasticity will have a value of 1 and the base is typically short. Natural viewing would equal to base lengths of human eyes, i.e. to 65 mm. We present in the paper also the Stereodrome, which is a physical realization of full-scale stereo viewing. Originally we have motivated us for building the Stereodrome by the fact that it is the only means to really see the behavior of 3D point clouds in details.
Proceedings of SPIE, Jul 7, 1997
ABSTRACT
Extracting forest variables from airborne laser scanner has less than 10 years of history. During... more Extracting forest variables from airborne laser scanner has less than 10 years of history. During that time, however, a new area in the field of forest studies has emerged. This paper describes existing algorithms and methods of airborne laser scanning that are used for forest measurements. The methods are divided into the following categories: 1) extraction of DTM (digital terrain model), 2) extraction of canopy height, 3) extraction of statistical variables from laser data, 4) extraction of individual tree information using image processing techniques, 5) integrating aerial image data with laser scanner, 6) use of intensity and waveform information, and 7) use of change detection methods.
The economic recession has hit especially hard the residential building sector in the EU region, ... more The economic recession has hit especially hard the residential building sector in the EU region, e.g., the number of the housing completions has decreased -49% and the total residential output has been squeezed down by -24% between 2007 and 2014 (Euroconstruct, 2015). In turn, the aim of our paper is to suggest a set of radical, novel programmes for developing the national residential building sectors within EU member countries up to 2025. We have applied the framework of strategic niche management (SNM) to the diagnoses of the current portfolios of the innovation, R&D programs in our two member country contexts. In the case of the Northern Finland, the prime example is Hiukkavaara, the largest district to be built in the City of Oulu. Homes will be constructed for 20,000 new residents. Hiukkavaara is a model for climate-conscious design in the northern hemisphere. Energy and materials are conserved, nature is valued and human beings adapt to their environment. One sub-programme involves Future Buildings and Renewable Energy Project. In the case of the Netherlands, the prime example is Energiesprong (Energy Leap), i.e., the innovation programme commissioned by the Dutch Ministry of the Interior. The aim is to make buildings energy-neutral and boost large-scale initiatives. The sub-programmes are targeting homes owned by housing associations, privately owned homes, office buildings, shops and care institutions. This programme is about ensuring new supply by encouraging companies to package a variety of technical sub-solutions, full services and financing options as well as about asking clients to put out tenders and ask for quotes in novel ways, with the government making changes to the rules and the regulations. Experiences on which the Dutch case in this paper focuses are sub-programmes for residential buildings which includes Rapids, All Lights on Green and Our Home Deserves It. Based on the emerging Finnish and Dutch evidence, we are suggesting key elements to be incorporated into future national residential programmes within EU member countries on: (1) radical direction with balanced stakeholder groups, trustworthy advocates, contextual goal-setting and barriers management, (2) radical networking with entrepreneurial roles and causal links, novel expertise, transparent choices and digital platforms and (3) radical learning processes to arrive at better informed markets on user preferences, co-innovating, new rules and regulations, higher performance/price ratios, higher quality, new roles and responsibilities assignments.