Figure 7
(a) The basis of the DTI 3D auto-stereoscopic display. (b) DTI's 15 inch and (c) 18 inch display monitors (Source: Dimension Technologies Inc.)
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With the increasing availability of digital imagery for use in mapping and GIS operations, the whole matter of the 3D stereoscopic viewing of aerial and space imagery has been undergoing a radical change. The reasons are varied. On the one hand, we have seen the widespread adoption of the digital photogrammetric workstation (DPW). In association wi...
Citations
... There are even applications that can be installed on mobile devices, allowing the user to create 3D maps using just an iPad (https://3dinsider.com/3d-mapping-cameras/). The result is a faithful reproduction of the 3D area, without any parallax, ie the end result for a single observation is a stereoscopic 3D image ( Figure 2) (Biljecki, 2017). External instruments, such as 3D glasses, a special cursor (topo-mouse) and a 3D monitor are needed to generate, view and measure objects in a stereoscopic environment (Petrie, 2001). The workflow (Figure 3) for obtaining a stereo-model is the same as the one for a photogrammetry project, starting with the data acquisition and ending with the map's generation. ...
In the last 15 years, mapping technology has become a necessity in smart cities planning. And 2D are starting to be augmented by 3D maps. 3D Maps are already used in the cartographic field, to create a three-dimensional view of the terrain and buildings. In this paper we address the concept of 3D Maps and we compare two methods to generate such maps. In this study two 3D maps were built, one using photogrammetric 3D stereo-restitution and one using automatic extrusion from a LiDAR point cloud and a set of 2D vector polygons. Upon comparison of these maps, we have concluded that the accuracy of the two maps is very similar and it depends very much on the input data and we have observed that creating a precise 3D map in photogrammetric environment takes much longer than the one built using the LiDAR point cloud. As 3D maps become the future of mapping, there is a continuous need for more accurate and complete field data to be collected and processed. Once more detailed field data becomes available, a clear conclusion on which of the methods provide us with a more accurate 3D map could be drawn. The evolution of 3D mapping is rapidly growing together with the applications developed to use it, especially in surveying and material monitoring. The key to future development of smart cities in based on better designs and infrastructures, and 3D mapping technology is a vital instrument to assist such a development.
... Rozwój pierwszych cyfrowych stacji fotogrametrycznych (lata 90-te XX w.) przyczynił się do opracowania szeregu metod stosowanych do uzyskania efektu stereoskopowego, wykorzystujących obrazy cyfrowe (Petrie, 2001;Domański, 2010;Kurczyński, 2014). Metody te, to m. in.: ─ wyświetlanie zdjęć stereopary na dwóch ekranach, lub na połówkach jednego ekranu i ich obserwacja metodą optyczną z wykorzystaniem okularów pryzmatycznych, lub z pomocą odpowiedniego układu zwierciadeł. ...
... Jedynie w trzecim przypadku przestrzenny obraz postrzegany jest jako kolorowy (Peinsipp-Byma et al., 2009;Rojas et al., 2014). Pomimo tych ograniczeń, użycie anaglifów jest prawdopodobnie najbardziej rozpowszechnioną metodą wizualizacji stereoskopowej, w zakresie fotointerpretacji różnych zjawisk, a popularność tej metody wynika zarówno z faktu niewielkich kosztów okularów z kolorowymi filtrami, stosunkowej łatwości przygotowania obrazów do wizualizacji (przy użyciu odpowiedniego oprogramowania), jak też możliwości zastosowania różnych mediów do prezentacji, w tym także papieru, co znajduje odbicie w obecnych na rynku publikacjach zawierających obrazy anaglifowe (Petrie, 2001;Rojas et al., 2014). Ten sposób prezentacji wykorzystano w Polsce np. ...
... Jednym z rodzajów urządzeń VR umożliwiających prezentację stereoskopową są okulary działające w zestawie z urządzeniem przenośnym (najczęściej smartfonem). Są one współczesną wersją stereoskopu optycznego i wykorzystują najprostszy sposób wizualizacji stereoskopowej, którego ogólne podstawy są stosowane także w stacjach fotogrametrycznych (Petrie, 2001). ...
Uzyskanie efektu widzenia przestrzennego osiąganego w trakcie stereoskopowej obserwacji par obrazów (np. zdjęć lotniczych) pozwala na lepsze zrozumienie analizowanej sceny. W prezentacji stereoskopowej obrazów stosuje się obecnie różne metody wykorzystujące m. in. dodatkowe urządzenia – okulary o różnej konstrukcji, lub ekrany o specjalnej powłoce. Poza koniecznością stosowania dodatkowego sprzętu, czy użycia specjalistycznego oprogramowania do wstępnego przetwarzania obrazów wejściowych, część ze wspomnianych metod napotyka ograniczenia związane z możliwością pracy jedynie z obrazami w odcieniach szarości, czy wiąże się z trudnym do wyeliminowania dyskomfortem. Celem niniejszej pracy było zbudowanie systemu prezentacji stereoskopowej zdjęć lotniczych, który połączy w sobie możliwości technologii urządzeń przenośnych, oprogramowanie webGIS i technologię tzw. „wirtualnej rzeczywistości” (ang. Virtual Reality, VR). Metoda prezentacji stereoskopowej dobrana została tak, by zminimalizować ewentualny dyskomfort i móc maksymalnie wykorzystać możliwości jakie dają wspomniane technologie. Narzędzie działa w oparciu o bibliotekę Leaflet (JavaScript) stosowaną przy projektowaniu internetowych serwisów mapowych (geoportali). Zostało ono przygotowane tak, by w obserwacji stereopar można było wykorzystać okulary VR przeznaczone do współpracy z urządzeniami mobilnymi, takimi jak smartfon.
... The current 3D digital stereogram viewing methods (Table 2) can be summarized as follows (Petrie 2001; Olm and Gaffney 2010): ...
... The use of digital imagery in large scale mapping applications and GIS requires precise measurement of 3D information. The 3D stereo-viewing of images, improves the interpretation and measurement of imagery of almost all types of terrain (petrie, 2001). In this regard, stereoscopic depth perception plays a vital role in photogrammetry as it enables the formation of a 3D stereomodel by viewing a pair of overlapping photographs. ...
Stereoscopic depth perception plays a vital role in photogrammetry, as it enables the formation of a 3-D stereo model by viewing a pair of overlapping photographs. The stereo model can then be studied, measured and mapped. In this study, the stereoscopic measurements of images from Ultracam-D digital camera, acquired at 10cm GSD are investigated by carrying out repetitive measurements of various geometric features by an experienced photogrammetrist. The features selected for measurements are having different contrast like dark tonal variations in shadows and bright tonal variations with bright background. The measurements are validated with that of ground values to evaluate the achievable horizontal and vertical accuracy. Traditional standards for map accuracy give the horizontal accuracy as 0.25mm of map scale and vertical accuracy in terms of contour interval. The study shows the images acquired with high radiometry and color information helps to measure the features in low contrast conditions with reasonable good accuracy. In this study the root mean square error (RMSE) achieved in different contrast conditions and for different geometrical features are 7.7cm in horizontal and 12.5cm in vertical. The results shows, by using 10cm GSD color data, geospatial information at 1:500 scale can be prepared with 0.5 m contour interval.
... The current 3D digital stereogram viewing methods (Table 2) can be summarized as follows (Petrie 2001; Olm and Gaffney 2010): ...
... The current 3D digital stereogram viewing methods (Table 2) can be summarized as follows (Petrie 2001; Olm and Gaffney 2010): ...
Development of landslide inventories based on remote sensing techniques has become one of the main tools in assessment of hazards and risk. Among those techniques, visual and automatic and semi-automatic analysis of high- and very highresolution (VHR) satellite images, or a combination ofthese, has recently been considered as a promising way to identify and map landslides at local and regional scales. In this context, a landslide inventory for the municipality of Pahuatlán, Puebla, in central Mexico was prepared by combining three techniques: (1) visual analysis of stereoscopic pairs of VHR satellite images (GeoEye-1), (2) visual analysis of monoscopic VHR satellite images (SPOT 5 and Google Earth images), and (3) field surveying. In this paper, particular attention is given to landslide identification and mapping based on the GeoEye-1 stereo-pairs. Additionally, as a preliminary step in the use of VHR imagery, a general review is presented of the available VHR satellite images, software and hardware that can be useful for digital mapping of landslides. The landslide inventory included a total of 577 landslides, corresponding to an average density of 10.5 landslides per km2. Of these, 385 were classified as recent, 171 as old, and 21 as very old, regardless of state of activity. The total mapped area was 54.9km2; 57.7% of it had been affected by landsliding. The mean area occupied by recent landslides was of the order of 1,066m2; for old landslides, it was 82,559m2 and for very old landslides 1,173,952m2. Debris flows were the most frequent type of movement (217), followed by 167 translational slides, 97 complex movements, 79 rotational slides, and 17 falls and topples. The cost–benefit relationships of a number of these techniques remain debatable because of the high cost of some of the VHR images and the related software and hardware.However, the appearance of new satellite sens ors is likely to generate market competence, so this type of image will probably be available at a much lower cost in the near future. Additionally, it is important to consider that the use of several stereo-high-resolution images involves no cost, as downloading high-resolution images from Google Earth, using Google Earth Pro is currently available. The relative rapidity of these techniques can be highly valuable after a regional landslide disaster has occurred, since damage to roads and infrastructure usually prevents the rapid and accurate evaluation of the impact of landsliding. Most importantly, these techniques can be of great value for hazard evaluation of potentially unstable inhabited slopes.
... In contrast to the traditional stereo technology, autostereo is goggle-free or aid-free (Okoshi 1976;Eichenlaub and Martens, 1990;Pastoor and Wöpking, 1997). Its potential utilization in photogrammetric practice has been brought to the attention of photogrammetrists and photogrammetry vendors (Petrie, 2001). ...
Stereoscopic perception is a basic requirement for photogrammetric 3D measurement and accurate geospatial data collection. Ordinary stereoscopic techniques require operators wearing glasses or using eyepieces for interpretation and measurement. However, the recent emerging autostereoscopic technology makes it possible to eliminate this requirement. This paper studies the principles and implementation of autostereoscopic photogrammetric measurement and evaluates its performance. We first describe the principles and properties of the parallax barrier-based autostereoscopic display used in this study. As an important metric property, we quantitatively present the autostereoscopic geometry, including viewing zones and the boundary of a viewer’s movement for autostereoscopic measurement. A toolkit AUTO3D is developed that has common photogrammetric functions. The implementation principles are described by addressing the differences compared to the ordinary stereoscopic technology. To evaluate the performance of the auto-stereoscopic measurement, images at a resolution of 25 m and 50 m are measured by a group of seven (7) operators, who are asked to digitize 18 well-defined roof points and 18 ground points. These results are evaluated by comparing the same measurements obtained from a popular stereoscopic photogrammetric workstation. It is shown that the precision of autostereoscopic measurement is about 16 percent to 25 percent lower than the conventional stereo workstation.
... Although photogrammetry has been using stereo instruments for over a century, continuous development in stereo display industry provides many alternatives. In particular, the recent autostereoscopic technology has been brought into the attention of photogrammetrists and photogrammetry instrument vendors (Petrie, 2001). In contrast to the traditional photogrammetric technologies, autostereoscopic measurement is goggle-free (Okoshi 1980;Motoki et al 1995) or aid-free (Petrie, 2001), and can be used in mobile and field environment. ...
... In particular, the recent autostereoscopic technology has been brought into the attention of photogrammetrists and photogrammetry instrument vendors (Petrie, 2001). In contrast to the traditional photogrammetric technologies, autostereoscopic measurement is goggle-free (Okoshi 1980;Motoki et al 1995) or aid-free (Petrie, 2001), and can be used in mobile and field environment. This advantage contributes possible technical alternatives in photogrammetric practice and attracts emerging research on autostereoscopic mapping and interpretation system (Petrie, 2001). ...
... In contrast to the traditional photogrammetric technologies, autostereoscopic measurement is goggle-free (Okoshi 1980;Motoki et al 1995) or aid-free (Petrie, 2001), and can be used in mobile and field environment. This advantage contributes possible technical alternatives in photogrammetric practice and attracts emerging research on autostereoscopic mapping and interpretation system (Petrie, 2001). ...
Autostereoscope is a technology that allows for a viewer to obtain stereoscopic effect without wearing glasses. This may potentially be used as a replacement or alternative to the current goggle-based stereoscopic technologies used in visualization and mapping practice. This paper studies the principles of popular autostereoscopic technologies, fundamental issues in using this technology for visualization, photogrammetry, and the performance of autostereoscopic photogrammetric measurement. In particular, the autostereoscopic effect is studied in terms of viewing zone and perceived depth. As a fundamental step towards autostereoscopic photogrammetry, the imaging geometry of such displays is analytically presented. To evaluate the properties and performance of the autostereoscopic measurement, we conduct a series of experiments using a backlight autostereoscopic display. A stereo pair at a pixel size of 25 and 50 microns are used in the study. Three dozens of well defined and easily identified feature points are measured by seven operators using the developed autostereoscopic measurement toolkit Auto3D. The consistency of these measurement results is analyzed. In addition, they are also compared with the ones obtained from regular stereoscopic display. The work is a primary effort towards lighter and mobile image interpretation and measurement environment.
... Chromo-stereoscopy [9,10,17,19,20] as an optical phenomenon, also known as color-stereo effect, was already described by Einthoven in 1885. The human eye refracts light in a color dependent manner, so that light rays with different wavelength (color) are projected onto different positions on the retina. ...
... These so-called ChromaDepth TM glasses are trademarked by Chromatek [4]. Because of the simple image generation, the ChromaDepth TM glasses are a low-budget alternative to other stereoscopic methods [10] for various applications and fields. Chromo-stereoscopy offers a real depth perception in comparison to other 3D visualization techniques, which just project a 3D model onto a 2D image plane. ...
Due to characteristics of the human visual system different colors induce different depth perception. This chromo-stereoscopy has been already used for 3D data to enhance a third spatial dimension. We propose to use chromo-stereoscopy for 2D abstract data. Color coding introduces a depth cue which encodes relevance with chromo-stereoscopy. The focus information literally "stands out" as compared to the context information. We applied this technique on two-dimensional graphs and multi-layer representations. Our approach can also be easily combined with other focus+context methods.
... Although the development of photogrammetry in the past century witnessed three different phases: analogue, analytical and digital photogrammetry, all of them use eyepieces or glasses to obtain stereoscopic view based on which mapping and interpretation are conducted. Recent development in autostereoscopic devices/monitors [Meritt and Fisher, 1993;Petrie, 2001] makes it possible to perform photogrammetric practices without using goggles, eyepieces or other viewing aids. ...
... Early thought on this technology to be used for photogrammetry is presented by [Petrie, 2001]. However, the primary application fields of this technology are collective visualization and image interpretation. ...
Stereoscopic perception is a fundamental requirement for photogrammetric 3D measurement and accurate geographic data collection. Traditional stereoscopic techniques require operators wearing glasses or using eyepieces during the measurement and interpretation process. However, the recent emerging autostereoscopic technique makes it possible to eliminate this requirement. This paper studies the principles and implementation of autostereoscopic photogrammetric measurement. After reviewing the available technologies of autostereoscopic display, we address the principles and properties of backlight autostereoscopic display used in this study. Their possible effects on 3D viewing and measurement are discussed. To accomplish and evaluate autostereoscopic measurement, a 3D toolbox Auto3D is developed that has common photogrammetric functions, such as Y-parallax removal, adjusting x-parallax, point labeling and image rotation. The autostereoscopic measurement is achieved by adjusting the two images until the 3D cursor rests on the exact feature locations of left and right images. To evaluate the performance of the autostereoscopic measurement, images at resolution of 25 and 50 microns are measured by a group of seven students, who are asked to digitize well defined roof and ground points. Results of theoretical study and analysis on the measurements are presented. As a conclusion, the experience on this novel technology is addressed based on the measurement outcome.
