The Use of Gigapixel Photogrammetry for the Understanding of Landslide Processes in Alpine Terrain

The work in this paper illustrates an experimental application for geosciences by coupling new and low cost photogrammetric techniques: Gigapixel and Structure-from-Motion (SfM). Gigapixel photography is a digital image composed of billions of pixels (≥1000 megapixels) obtained from a conventional Digital single-lens reflex camera (DSLR), whereas the SfM technique obtains three-dimensional (3D) information from two-dimensional (2D) image sequences. The field test was carried out at the Ingelsberg slope (Bad Hofgastein, Austria), which hosts one of the most dangerous landslides in the Salzburg Land. The stereographic analysis carried out on the preliminary 3D model, integrated with Ground Based Synthetic Aperture Radar Interferometry (GBInSAR) data, allowed us to obtain the main fractures and discontinuities of the unstable rock mass.

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Assessing the Accuracy of Digital Surface Models Derived from Optical Imagery Acquired with Unmanned Aerial Systems

Drones ◽

10.3390/drones3010015 ◽

2019 ◽

Vol 3 (1) ◽

pp. 15 ◽

Cited By ~ 18

Author(s):

Salvatore Manfreda ◽

Petr Dvorak ◽

Jana Mullerova ◽

Sorin Herban ◽

Pietro Vuono ◽

...

Keyword(s):

3D Model ◽

Low Cost ◽

Three Dimensional ◽

Careful Consideration ◽

Ground Control ◽

Unmanned Aerial Systems ◽

Control Points ◽

Earthen Dam ◽

Ground Control Points ◽

Aerial Systems

Small unmanned aerial systems (UASs) equipped with an optical camera are a cost-effective strategy for topographic surveys. These low-cost UASs can provide useful information for three-dimensional (3D) reconstruction even if they are equipped with a low-quality navigation system. To ensure the production of high-quality topographic models, careful consideration of the flight mode and proper distribution of ground control points are required. To this end, a commercial UAS was adopted to monitor a small earthen dam using different combinations of flight configurations and by adopting a variable number of ground control points (GCPs). The results highlight that optimization of both the choice and combination of flight plans can reduce the relative error of the 3D model to within two meters without the need to include GCPs. However, the use of GCPs greatly improved the quality of the topographic survey, reducing error to the order of a few centimeters. The combined use of images extracted from two flights, one with a camera mounted at nadir and the second with a 20° angle, was found to be beneficial for increasing the overall accuracy of the 3D model and especially the vertical precision.

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Research on the Platform of 3D Information Management for the Ordnance Maintenance Equipment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.989-994.5427 ◽

2014 ◽

Vol 989-994 ◽

pp. 5427-5430

Author(s):

Zhi Yong Cheng ◽

Rong Yue Xie ◽

Lei Qiu ◽

Xiao Zhou ◽

Chao Fa Yu

Keyword(s):

Information Management ◽

Management System ◽

3D Model ◽

Three Dimensional ◽

Original Data ◽

Information Management System ◽

Equipment Management ◽

Two Dimensional ◽

New Information ◽

3D Information

Based on the current situation that the current ordnance equipment maintenance information management system is not intuitive, a new information system was designed and realized, which could display the two-dimensional Information and three-dimensional information synchronously. This system can well compatible with the existing one. Through studying the analysis of the original data structure, importing way for the 3D model of equipment, synchronous display for the 2D information and 3d model, the 3D information management system was realized, which provides a new digital method for equipment management person.

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Fabrication of 3D Models for Microtia Reconstruction Using Smartphone-Based Technology

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894211024051 ◽

2021 ◽

pp. 000348942110240

Author(s):

Peng You ◽

Yi-Chun Carol Liu ◽

Rodrigo C. Silva

Keyword(s):

3D Model ◽

Low Cost ◽

Tertiary Care ◽

Three Dimensional ◽

Basic Research ◽

3D Models ◽

University Hospital ◽

Patient Specific ◽

Surface Scanning ◽

Barrier To Entry

Objective: Microtia reconstruction is technically challenging due to the intricate contours of the ear. It is common practice to use a two-dimensional tracing of the patient’s normal ear as a template for the reconstruction of the affected side. Recent advances in three-dimensional (3D) surface scanning and printing have expanded the ability to create surgical models preoperatively. This study aims to describe a simple and affordable process to fabricate patient-specific 3D ear models for use in the operating room. Study design: Applied basic research on a novel 3D optical scanning and fabrication pathway for microtia reconstruction. Setting: Tertiary care university hospital. Methods: Optical surface scanning of the patient’s normal ear was completed using a smartphone with facial recognition capability. The Heges application used the phone’s camera to capture the 3D image. The 3D model was digitally isolated and mirrored using the Meshmixer software and printed with a 3D printer (MonopriceTM Select Mini V2) using polylactic acid filaments. Results: The 3D model of the ear served as a helpful intraoperative reference and an adjunct to the traditional 2D template. Collectively, time for imaging acquisition, editing, and fabrication was approximately 3.5 hours. The upfront cost was around $210, and the recurring cost was approximately $0.35 per ear model. Conclusion: A novel, low-cost approach to fabricate customized 3D models of the ear is introduced. It is feasible to create individualized 3D models using currently available consumer technology. The low barrier to entry raises the possibility for clinicians to incorporate 3D printing into various clinical applications.

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Use of Smartphone-Based Head-Mounted Display Devices to View a Three-Dimensional Dissection Model in a Virtual Reality Environment: Pilot Questionnaire Study (Preprint)

10.2196/preprints.11921 ◽

2018 ◽

Author(s):

Yoshihito Masuoka ◽

Hiroyuki Morikawa ◽

Takashi Kawai ◽

Toshio Nakagohri

Keyword(s):

Virtual Reality ◽

Motion Sickness ◽

3D Model ◽

Low Cost ◽

Three Dimensional ◽

Visually Induced Motion Sickness ◽

Head Mounted Display ◽

Eye Fatigue ◽

Induced Motion ◽

Observation Environment

BACKGROUND Virtual reality (VR) technology has started to gain attention as a form of surgical support in medical settings. Likewise, the widespread use of smartphones has resulted in the development of various medical applications; for example, Google Cardboard, which can be used to build simple head-mounted displays (HMDs). However, because of the absence of observed and reported outcomes of the use of three-dimensional (3D) organ models in relevant environments, we have yet to determine the effects of or issues with the use of such VR technology. OBJECTIVE The aim of this paper was to study the issues that arise while observing a 3D model of an organ that is created based on an actual surgical case through the use of a smartphone-based simple HMD. Upon completion, we evaluated and gathered feedback on the performance and usability of the simple observation environment we had created. METHODS We downloaded our data to a smartphone (Galaxy S6; Samsung, Seoul, Korea) and created a simple HMD system using Google Cardboard (Google). A total of 17 medical students performed 2 experiments: an observation conducted by a single observer and another one carried out by multiple observers using a simple HMD. Afterward, they assessed the results by responding to a questionnaire survey. RESULTS We received a largely favorable response in the evaluation of the dissection model, but also a low score because of visually induced motion sickness and eye fatigue. In an introspective report on simultaneous observations made by multiple observers, positive opinions indicated clear image quality and shared understanding, but displeasure caused by visually induced motion sickness, eye fatigue, and hardware problems was also expressed. CONCLUSIONS We established a simple system that enables multiple persons to observe a 3D model. Although the observation conducted by multiple observers was successful, problems likely arose because of poor smartphone performance. Therefore, smartphone performance improvement may be a key factor in establishing a low-cost and user-friendly 3D observation environment.

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ANALYSIS OF DIFFERENCES IN 3D BUILDING INFORMATION MODELING

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-5-w2-65-2019 ◽

2019 ◽

Vol XLII-5/W2 ◽

pp. 65-69

Author(s):

J. Suziedelyte Visockiene ◽

E. Tumeliene

Keyword(s):

Construction Projects ◽

3D Model ◽

Low Cost ◽

Three Dimensional ◽

3D Models ◽

Information Modeling ◽

Corrected Image ◽

Architectural Model ◽

Building Information ◽

The Impact

<p><strong>Abstract.</strong> The implementation of Building Information Modelling (BIM) in each project, which is planned, have a design and construction stages. In the construction stage the objects are modelled by architects, engineers, and surveyors. Modelling process allowed to construct a BIM, which replaces two-dimensional (2D) building information into a three-dimensional (3D). Noticed that 3D BIM created by surveyors is not the same as 3D BIM, which is created by architects. Therefore, the purpose of this study is to identify the differences of the created 2D draftings made by 3D models between surveyors and architect’s. The surveyors make their model by using Unnamed Aerial Vehicle (UAV) system: Airborne Drone Data and Data photogrammetric processing technology. The 3D models accuracy is assessed by UAV images processing. The 3D information should be used to calculate façade geometry, volume, distances, contours, which are in the shadowed side of the house, and create 2D façade draftings. Traditionally, architects used 2D building’s façade draftings for pre-design in Construction Projects (CP). 3D architectural model is created by using structural 2D draftings created with Autodesk software. The architectural 3D model is more convenient for the general design and the visual view, it is easily to evaluate the impact of the changes that will be made. The 3D architectural model helps to finish a project at a low cost and also to evaluate the effect of the changes made. The 3D model from surveys measurements shows real view of an object (with deformations), meanwhile the 3D model from architects is a corrected image. Discrepancies between surveyors and architect’s 2D models made by 3D virtual reality (VR) are analysed in this article.</p>

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3D Reconstruction of Exposed Underground Utilities Using Photogrammetric Methods

10.32920/ryerson.14644020.v1 ◽

2021 ◽

Author(s):

Wensong Hu

Keyword(s):

3D Reconstruction ◽

Digital Images ◽

Low Cost ◽

Three Dimensional ◽

Lookup Table ◽

Image Point ◽

Digital Cameras ◽

Study Results ◽

Underground Utilities ◽

3D Information

This thesis addresses the topic of three-dimensional (3D) reconstruction of exposed underground utilities using photogrammetric methods. Research on this topic is mainly motivated by the need for improved information on the location of underground utilities and, thus, to provide reliable information for the management of buried assets. In this thesis, a system of photogrammetric software programs is developed for 3D reconstruction of underground utilities. Camera calibration programs are used for computing interior elements and lens distortion coefficients of digital cameras and saving them in a lookup table (LUT). The accuracy of calibrated image coordinates satisfies the photogrammetric processing demand. An automatic image point detection method is proposed and achieved in these programs. External orientation programs are used for calculating exterior elements of the digital images. Based on geographic information system (GIS) and global positioning system (GPS) techniques, a new ground control points (GCPs) collection method is proposed and implemented in these programs. A 3D reconstruction program provides corresponding functions to obtain and edit 3D information of underground utilities. Epipolar lines are employed as an assisting tool that helps operators easily find homologous points from different digital images. The study results indicate that photogrammetric methods for reconstructing 3D information of underground utilities are effective and low cost.

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Three-Dimensional Pathology Specimen Modeling Using “Structure-From-Motion” Photogrammetry: A Powerful New Tool for Surgical Pathology

Archives of Pathology & Laboratory Medicine ◽

10.5858/arpa.2017-0145-oa ◽

2018 ◽

Vol 142 (11) ◽

pp. 1415-1420 ◽

Cited By ~ 5

Author(s):

John Turchini ◽

Michael E. Buckland ◽

Anthony J. Gill ◽

Shane Battye

Keyword(s):

Medical Education ◽

Structure From Motion ◽

3D Model ◽

Digital Pathology ◽

Three Dimensional ◽

Surgical Pathology ◽

Single Lens ◽

Data Points ◽

3D Photogrammetry ◽

Pathology Specimen

Context.— Three-dimensional (3D) photogrammetry is a method of image-based modeling in which data points in digital images, taken from offset viewpoints, are analyzed to generate a 3D model. This modeling technique has been widely used in the context of geomorphology and artificial imagery, but has yet to be used within the realm of anatomic pathology. Objective.— To describe the application of a 3D photogrammetry system capable of producing high-quality 3D digital models and its uses in routine surgical pathology practice as well as medical education. Design.— We modeled specimens received in the 2 participating laboratories. The capture and photogrammetry process was automated using user control software, a digital single-lens reflex camera, and digital turntable, to generate a 3D model with the output in a PDF file. Results.— The entity demonstrated in each specimen was well demarcated and easily identified. Adjacent normal tissue could also be easily distinguished. Colors were preserved. The concave shapes of any cystic structures or normal convex rounded structures were discernable. Surgically important regions were identifiable. Conclusions.— Macroscopic 3D modeling of specimens can be achieved through Structure-From-Motion photogrammetry technology and can be applied quickly and easily in routine laboratory practice. There are numerous advantages to the use of 3D photogrammetry in pathology, including improved clinicopathologic correlation for the surgeon and enhanced medical education, revolutionizing the digital pathology museum with virtual reality environments and 3D-printing specimen models.

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Effectiveness of an Immersive Virtual Environment for Collaboration With Gesture Support Using Low-Cost Hardware

Journal of Mechanical Design ◽

10.1115/1.4039006 ◽

2018 ◽

Vol 140 (4) ◽

Cited By ~ 3

Author(s):

Joshua Q. Coburn ◽

John L. Salmon ◽

Ian Freeman

Keyword(s):

Computer Aided Design ◽

Global Economy ◽

Low Cost ◽

Three Dimensional ◽

Physical Models ◽

Remote Collaboration ◽

Immersive Virtual Environment ◽

Modern Computer ◽

Collaborative Environment ◽

3D Information

Since the advent of modern computer-aided design software, engineers have been divorced from the highly collaborative environment previously enjoyed. Today's highly complex designs require modern software tools and the realities of a global economy often constrain engineers to remote collaboration. These conditions make it highly impractical to collaborate locally around physical models. Various approaches to creating new collaboration tools and software, which alleviate these issues, have been tried previously. However, past solutions either used expensive hardware, which is not widely available, or used standard two-dimensional (2D) monitors to share three-dimensional (3D) information. Recently, new low-cost virtual reality (VR) hardware has been introduced, which creates a highly immersive 3D experience at a tiny fraction of the cost of previous hardware. This work demonstrates an immersive collaborative environment built using a network of this hardware, which allows users to interact with gestures virtually and conducts a study to show its advantages over traditional video conferencing software.

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Evaluating Feature Extraction Methods with Synthetic Noise Patterns for Image-Based Modelling of Texture-Less Objects

Remote Sensing ◽

10.3390/rs12233886 ◽

2020 ◽

Vol 12 (23) ◽

pp. 3886

Author(s):

Jahanzeb Hafeez ◽

Jaehyun Lee ◽

Soonchul Kwon ◽

Sungjae Ha ◽

Gitaek Hur ◽

...

Keyword(s):

Feature Extraction ◽

3D Reconstruction ◽

Feature Matching ◽

Low Cost ◽

Three Dimensional ◽

Extraction Methods ◽

Planar Surfaces ◽

Vision Sensors ◽

3D Printed ◽

3D Information

Image-based three-dimensional (3D) reconstruction is a process of extracting 3D information from an object or entire scene while using low-cost vision sensors. A structure-from-motion coupled with multi-view stereo (SFM-MVS) pipeline is a widely used technique that allows 3D reconstruction from a collection of unordered images. The SFM-MVS pipeline typically comprises different processing steps, including feature extraction and feature matching, which provide the basis for automatic 3D reconstruction. However, surfaces with poor visual texture (repetitive, monotone, etc.) challenge the feature extraction and matching stage and affect the quality of reconstruction. The projection of image patterns while using a video projector during the image acquisition process is a well-known technique that has been shown to be successful for such surfaces. In this study, we evaluate the performance of different feature extraction methods on texture-less surfaces with the application of synthetically generated noise patterns (images). Seven state-of-the-art feature extraction methods (HARRIS, Shi-Tomasi, MSER, SIFT, SURF, KAZE, and BRISK) are evaluated on problematic surfaces in two experimental phases. In the first phase, the 3D reconstruction of real and virtual planar surfaces evaluates image patterns while using all feature extraction methods, where the patterns with uniform histograms have the most suitable morphological features. The best performing pattern from Phase One is used in Phase Two experiments in order to recreate a polygonal model of a 3D printed object using all of the feature extraction methods. The KAZE algorithm achieved the lowest standard deviation and mean distance values of 0.0635 mm and −0.00921 mm, respectively.

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Line Drawing Extraction from Cartoons Using a Conditional Generative Adversarial Network

Applied Sciences ◽

10.3390/app11167536 ◽

2021 ◽

Vol 11 (16) ◽

pp. 7536

Author(s):

Kyungho Yu ◽

Juhyeon Noh ◽

Hee-Deok Yang

Keyword(s):

3D Model ◽

Line Drawing ◽

Three Dimensional ◽

Generative Adversarial Network ◽

Line Drawings ◽

Geometric Characteristics ◽

Adversarial Network ◽

Time Required ◽

3D Information ◽

3D Content

Recently, three-dimensional (3D) content used in various fields has attracted attention owing to the development of virtual reality and augmented reality technologies. To produce 3D content, we need to model the objects as vertices. However, high-quality modeling is time-consuming and costly. Drawing-based modeling is a technique that shortens the time required for modeling. It refers to creating a 3D model based on a user’s line drawing, which is a 3D feature represented by two-dimensional (2D) lines. The extracted line drawing provides information about a 3D model in the 2D space. It is sometimes necessary to generate a line drawing from a 2D cartoon image to represent the 3D information of a 2D cartoon image. The extraction of consistent line drawings from 2D cartoons is difficult because the styles and techniques differ depending on the designer who produces the 2D cartoons. Therefore, it is necessary to extract line drawings that show the geometric characteristics well in 2D cartoon shapes of various styles. This paper proposes a method for automatically extracting line drawings. The 2D cartoon shading image and line drawings are learned using a conditional generative adversarial network model, which outputs the line drawings of the cartoon artwork. The experimental results show that the proposed method can obtain line drawings representing the 3D geometric characteristics with a 2D line when a 2D cartoon painting is used as the input.

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