Image-based Modeling Techniques Research Articles

CRBeDaSet: A Benchmark Dataset for High Accuracy Close Range 3D Object Reconstruction

This paper presents the CRBeDaSet—a new benchmark dataset designed for evaluating close range, image-based 3D modeling and reconstruction techniques, and the first empirical experiences of its use. The test object is a medium-sized building. Diverse textures characterize the surface of elevations. The dataset contains: the geodetic spatial control network (12 stabilized ground points determined using iterative multi-observation parametric adjustment) and the photogrammetric network (32 artificial signalized and 18 defined natural control points), measured using Leica TS30 total station and 36 terrestrial, mainly convergent photos, acquired from elevated camera standpoints with non-metric digital single-lens reflex Nikon D5100 camera (ground sample distance approx. 3 mm), the complex results of the bundle block adjustment with simultaneous camera calibration performed in the Pictran software package, and the colored point clouds (ca. 250 million points) from terrestrial laser scanning acquired using the Leica ScanStation C10 and post-processed in the Leica Cyclone™ SCAN software (ver. 2022.1.1) which were denoized, filtered, and classified using LoD3 standard (ca. 62 million points). The existing datasets and benchmarks were also described and evaluated in the paper. The proposed photogrammetric dataset was experimentally tested in the open-source application GRAPHOS and the commercial suites ContextCapture, Metashape, PhotoScan, Pix4Dmapper, and RealityCapture. As the first experience in its evaluation, the difficulties and errors that occurred in the software used during dataset digital processing were shown and discussed. The proposed CRBeDaSet benchmark dataset allows obtaining high accuracy (“mm” range) of the photogrammetric 3D object reconstruction in close range, based on a multi-image view uncalibrated imagery, dense image matching techniques, and generated dense point clouds.

Volumetric Shrinkage Monitoring of Compacted Soil Specimens Using Image Based Modeling Technique

Volumetric Shrinkage Monitoring of Compacted Soil Specimens Using Image Based Modeling Technique

Geometric Tolerance Control Method for Precision Machinery Based on Image Modeling and Novel Saturation Function

Abstract Research on the geometric tolerance control method of precision machinery based on image modeling and new saturation function. First, image-based modeling techniques provide a new way to control the saturation function with a dynamic boundary layer from a computer graphics perspective. Then, it proposes a method to represent the dimensional and geometric tolerances of precision machines using changes in the position of control points of geometric elements. Finally, the main content of the tolerance analysis method based on Monte Carlo simulation is proposed, that is, the position of the azimuth control point of all geometric elements on the measurement chain is determined experimentally by using a random number generator. Experiments have shown that the nominal distance between the control points is the nominal size of the geometric elements, and by comparing the variation of the control points with the nominal distance of the control points, it is easy to determine the relationship between tolerance and tolerance. accuracy.

Documenting Cultural Heritage in very hostile fruition contexts: the synoptic visualization of Giottesque frescoes by Multispectral and 3D Close-range Imaging

Abstract The paper reports the results obtained from the digital survey of Giottesque frescoes in the Archiepiscopal Palace of Milan. Multispectral Imaging and Image Based Modelling techniques have allowed the study, the high-resolution documentation and the virtual reassembly of the fragmented frescoes: the integration of spectral data with RGB ortho-images and 3D models has supported the interpretation of the pictorial cycle by virtually relocating the fresco fragments and evaluating their consistency from a technical, iconographic and art-historical point of view. The experimental results show that the proposed approach has great potential for the documentation of wall paintings preserved in highly hostile contexts of fruition. Due to its versatility and portability in the field, its sub-millimetric accuracy, and the different outputs that can be generated, Close-Range Digital Photogrammetry has proven to be the ideal tool in case of scattered and difficult-to-access data.

DEFORMABLE OBJECT REMOVAL VIA EXEMPLAR-BASED ALGORITHM FOR 3D MODEL OF HERITAGE STRUCTURES

Heritage structures are important for tourism and for learning about nations’ history. Historical sites around the world are in damaged conditions due to various factors from the environment, man-made activities or natural calamities. To ensure safety and avoid further deterioration, digital re- construction of heritage sites can be used to create 3D virtual models of these structures for archiving and for inspection purpose. This paper presents a technique to reconstruct a high-quality image-based 3D model of a heritage structure. An exemplar-based inpainting algorithm was used for removing deformable obstacles such as trees in 2D images since such obstacles are unwanted in a final 3D model. They also create noise in the 3D modeling process, which makes the final 3D model less accurate. In this paper, an inpainting algorithm is applied to generate implied texture to fill holes that occurred from removing objects so that the generated 3D model does not contain any hole and becomes watertight. The modified exemplar-based inpainting algorithm was implemented on 2D images to remove unwanted objects, and then the image-based 3D modeling technique was applied to create a 3D model that did not contain any unwanted objects. The results show that the final 3D model is more accurate when applied the object removal process and the model provides better visualization for heritage structures.

Operator-dependent variability of angiography-derived fractional flow reserve and the implications for treatment.

AimsTo extend the benefits of physiologically guided percutaneous coronary intervention to many more patients, angiography-derived, or ‘virtual’ fractional flow reserve (vFFR) has been developed, in which FFR is computed, based upon the images, instead of being measured invasively. The effect of operator experience with these methods upon vFFR accuracy remains unknown. We investigated variability in vFFR results based upon operator experience with image-based computational modelling techniques.Methods and resultsVirtual fractional flow reserve was computed using a proprietary method (VIRTUheart) from the invasive angiograms of patients with coronary artery disease. Each case was processed by an expert (>100 vFFR cases) and a non-expert (<20 vFFR cases) operator and results were compared. The primary outcome was the variability in vFFR between experts and non-experts and the impact this had upon treatment strategy (PCI vs. conservative management). Two hundred and thirty-one vessels (199 patients) were processed. Mean non-expert and expert vFFRs were similar overall [0.76 (0.13) and 0.77 (0.16)] but there was significant variability between individual results (variability coefficient 12%, intraclass correlation coefficient 0.58), with only moderate agreement (κ = 0.46), and this led to a statistically significant change in management strategy in 27% of cases. Variability was significantly lower, and agreement higher, for expert operators; a change in their recommended management occurred in 10% of repeated expert measurements and 14% of inter-expert measurements.ConclusionVirtual fractional flow reserve results are influenced by operator experience of vFFR processing. This had implications for treatment allocation. These results highlight the importance of training and quality assurance to ensure reliable, repeatable vFFR results.

Verification of numerical homogenization approach in predicting thermal conductivities of fiber reinforced composites with voids and randomly distributed fibers

The aim of this paper is to establish the homogenization approach that eliminates the difficulties encountered by the conventional numerical methods in analyzing thermal behavior of the multi-material component systems with minimum computational resources. Analysis of problems with intricacies or larger domains can be made simpler through finite element assisted homogenization approach. In this paper, applicability of homogenization approach is verified by considering two cases (i) composite with voids and (ii) composite with fibers distributed randomly. Fiber randomness case is investigated by Digital Image-Based (DIB) modeling technique in association with MATLAB’S image processing module. Also effect of transverse fiber crack on the effective thermal conductivity of the composite is studied. Results of homogenization approach compared with micro-mechanics approach yielded maximum percentage deviation of 1.72% for voids case and 1.49% for fiber randomness case.

On the Use of Historical Flights for the Urban Growth Analysis of Cities Through Time: The Case Study of Avila (Spain)

Historical aerial images are a unique and relatively unexplored means of deriving spatio-temporal information for scenes and landscapes. Such historical imagery can be combined with photointerpretation and image-based 3D modelling techniques, providing the fourth dimension of time to 3D geometrical representations. This allows urban planners, historians, and other specialists to identify, describe, and analyse changes in scenes and landscapes. Urban growth has an important impact on the sustainable development of cities. An important step for the analysis of urban growth is the identification of different urban sectors. To this end, this paper proposes a methodology for the 4D urban growth analysis of cities through time using a free and open source software developed by the authors. This approach uses the latest advances in photogrammetry, including the so-called incremental Structure from Motion, to evaluate the urbanistic changes of a city by means of confronting two-point clouds from different eras. The objectives of this paper are twofold: (i) first, the processing of historical aerial images using modern photogrammetric techniques; (ii) second, deriving spatio-temporal information for urban cities, offering a method for researchers to identify changes over time. In order to validate this method, the urban growth of the city of Avila between 1956 and 2017 was assessed taking the historical American flight of 1956 and the digital aerial flight of 2017. The results were statistically assessed according to georeferencing quality, confirming that the approach developed can be used to support urban growth analysis through time and providing relevant data in 2D and 3D.

A flexible and swift approach for 3D image–based survey in a cave

In the geomatics field, modelling and georeferencing complex speleological structures are some of the most challenging issues. The use of conventional survey methods (for example, those employing total stations or terrestrial laser scanner) becomes more difficult, especially because of the space constraints and the often critical light conditions. In this work, a flexible and swift methodology to survey an in-progress excavation is presented, through image-based modelling techniques. The proposed approach allows obtaining a reliable and georeferenced three-dimensional model of the underground environments, preserving the integrity of the scene. The 3D model is scaled and georeferenced through three ground control points located just outside the cave, using data acquired by a double-frequency GNSS receiver in static session mode. Further targets were employed to check the deformation of the model inside the cave. The surveys were conducted on two archaeological sites: La Sassa cave and Guattari cave, both located in southern Latium.

UAV-based 3D reconstruction for hoist site mapping and layout planning in petrochemical construction

Hoisting operations are an essential part of petrochemical plant construction. The pre-layout planning of hoisting facilities, including hoisted objects and cranes, is the key to ensuring the success of the entire construction. However, most current site layout planning methods optimize construction facilities from the 2D plane space, which makes the safety of large-scale hoisting difficult to guarantee. This work proposes an unmanned-aerial-vehicle-based 3D reconstruction for hoist site mapping and layout planning. The core of this study is to utilize real-time 3D spatial information as a constraint for hoisting facility layout planning. Improved image-based modeling techniques are used to reconstruct the 3D construction site model in real-time. The geometric parameters extracted by the site model support the mathematical programming model presented in this work for a safe and efficient rapid layout planning. The C101 tower hoisting in the construction of the Wuhan Petrochemical Plant is used to verify the effectiveness of the method. Calculation results show that the method can push the position and save planning time intelligently. Furthermore, this method can provide a new solution to hoisting safety and efficiency.

PHOTOGRAMMETRY FOR QUICK SURVEY IN EMERGENCY CONDITIONS: THE CASE OF VILLA GALVAGNINA

Abstract. Photogrammetry is a survey method that provides good quality results also by using basic photographic equipment and user-friendly, low-cost software. The advantages of the image-based modelling techniques compared with the traditional topographic tools are very significant in emergencies, when the time for the survey is limited and many buildings are involved, as usually happens in case of relevant seismic events. The goal of this study is to verify the quality of the models obtained from quick digital images acquisition, carried out under non-optimal lighting condition and no accessibility of the building. As case of study was chosen the main front of Villa Galvagnina in Moglia, a Renaissance hunting palace badly damaged by the earthquake of May 20, 2012. The modelling was performed using two different software, Agisoft Metashape and 3DFlow Zephyr. This paper presents a comparison between the results obtained using different datasets; the workflow, the difficulties encountered during the survey and the data processing methods are fully described and discussed.

A Survey on Image-Based Hair Modeling Technique

A Survey on Image-Based Hair Modeling Technique

Temporary Theatres and Andrea Palladio as a Set Designer

This paper treats studies on perspective published in sixteenth-century treatises as important sources for understanding Andrea Palladio’s connection with perspective and with the sets and scenic spaces he designed for the stage before the construction of the Teatro Olimpico in Vicenza (1580–1585). Written and visual traces of these ephemeral theatres and their sets are extant in the monochrome frescoes on the eastern wall of the Teatro Olimpico’s antiodeo, which represent 1561 and 1562 stagings of the plays Amor costante and Sofonisba. A survey of these frescoes using image-based modeling techniques is a preliminary necessary phase for building rigorous 3D models of Palladio’s illusionistic sets, which are strictly dependent on the harmonic and dimensional ratios that appear in contemporary treatises on perspective. All of these experiences can be considered as models to test that precise idea of Theatre which is revealed in the Teatro Olimpico in Vicenza.

THREE DIMENSIONAL RECONSTRUCTION WORKFLOWS FOR LOST CULTURAL HERITAGE MONUMENTS EXPLOITING PUBLIC DOMAIN AND PROFESSIONAL PHOTOGRAMMETRIC IMAGERY

Abstract. In our paper, we document experiments and results of image-based 3d reconstructions of famous heritage monuments which were recently damaged or completely destroyed by the so-called Islamic state in Syria and Iraq. The specific focus of our research is on the combined use of professional photogrammetric imagery and of publicly available imagery from the web for optimally 3d reconstructing those monuments. The investigated photogrammetric reconstruction techniques include automated bundle adjustment and dense multi-view 3d reconstruction using public domain and professional imagery on the one hand and an interactive polygonal modelling based on projected panoramas on the other. Our investigations show that the combination of these two image-based modelling techniques delivers better results in terms of model completeness, level of detail and appearance.

Utilising 3D Realistic Models in Serious Games for Cultural Heritage

In the cultural heritage field, many Serious Games applications have been developed whose goal is to educate players and users not particularly specialized or familiar with this field. On the other hand, 3D models of cultural heritage objects created with precise 3D modelling methods can be a very useful asset for these applications. In this paper a composite Serious Game for the Stoa of Attalos, a prominent monument in the Ancient Athens Agora, is developed and presented. 3D models are used, which were produced mainly with automated image based modelling techniques. The creation of the 3D models is described and presented along with the development of the application, which offers three options for the player. These options are: a quiz game, a 3D visual quiz and a virtual museum. The user interaction is described and, based on an evaluation questionnaire, the application is assessed by a group of people in the Cultural Heritage field.

Sharp volumetric billboard based characterization and modeling of complex 3D Ni/Al high energy ball milled composites

We present an innovative image-based modeling technique, based on Google Earth like algorithms, to effectively resolve intricate material morphology and address the computational complexity associated with heterogeneous materials. This sharp volumetric billboard algorithm stems from a volumetric billboard method, a multi-resolution modeling strategy in computer graphics. In this work, we enhance volumetric billboards through a sharpening filter to reconstruct the statistical information of heterogeneous systems. A hierarchy of microstructures is created for high energy ball milled Ni/Al composites. We analyze the first- and second-order statistics of microstructures, and characterize both macro- and micro-mechanical material responses. Furthermore, we conduct a convergence study of the associated computational results. The statistical and mechanical robustness of data compression is demonstrated through the corresponding error analysis.

Full Three-Dimensional Seismic Response Analysis of Underground Structures with Large Complex Cross Sections and Two-Step Analysis Method for Reducing the Computational Costs

To enhance the reliability of estimates of seismic behavior, with a special emphasis on quality assurance of numerical simulations, this paper presents a full three-dimensional (3D) seismic response analysis of a large underground structure with a complex cross section. We conduct a full 3D seismic-response analysis using a high-fidelity model with quality assurance and a high-performance computing technique in a supercomputer environment. Due to the large computational costs of such analyses, we propose a two-step numerical simulation method based on multi-scale analysis, image-based modeling, and sophisticated approximation techniques. We provide numerical examples showing that the method can successfully reproduce the dynamic behavior of a full 3D model, but with a considerable reduction in computational costs. Our method is expected to support practical seismic safety inspections and the design of underground structures with complex large-cross-sectional configurations, as it has already been applied to the practical seismic safety inspection of an actual underground highway.

Assessing the damage of an archaeological site: New contributions from the combination of image-based 3D modelling techniques and GIS

• 3D GIS as an exploratory environment for data analysis is put to the test. • A new method for measuring the damage occurred in an archaeological site is introduced. • Image-based 3D modelling techniques and GIS tools are combined together. • Vector and raster-based analysis is employed to evaluate the degree of erosion affecting some archaeological layers. • The proposed method can improve the strategies of land evaluation and risk assessment.

DIRECT CORONARY COUPLING APPROACH FOR COMPUTING FFRCT

With the advances in computational fluid dynamics (CFD) and image-based modeling techniques, fractional flow reserve (FFR) can be computed from coronary computed tomography angiography (CTA) scans (FFRCT). However, this non-invasive approach requires large-scale computational resources, which limits its application in routine clinical setting. A 3D–0D coupling approach is proposed to improve the coupling efficiency of FFRCT. Aortic–root is modeled by a lumped parameter model and connected with the models of left ventricle and systemic circulation. With this approach, the interested coronary regions can be directly coupled to the lumped parameter model, resulting in a significant reduction (up to 20 times reduction) in the volume of the CFD computing domain. The proposed approach is applied to a patient-specific model and compared with previous non-reduced approach. Results show that the computed coronary flow rates, pressure waveforms and FFRCT contours by the proposed approach are consistent well with that of the non-reduced approach. These results demonstrate that the proposed approach can reduce the CFD computing domain of FFRCT significantly while maintaining the similar accuracy as compared with the non-reduced approach, and it can be further employed to promote FFRCT in routine clinical setting.

Three-dimensional stress and strain around real shape Si particles in cast aluminum alloy under cyclic loading

The crack initiation mechanism of cast Al-Si-Mg alloy under low-cycle fatigue was addressed by using the synchrotron X-ray computed tomography (CT) and the image-based finite element analysis. The fatigue test and its in situ CT observation were conducted to visualize the crack initiation behavior. In the low-cycle fatigue, the cracking generally started with the voiding by the fracture of silicon particles, and the coalescence of these voids formed the crack. To elucidate the mechanism of silicon particle fracture, the finite element elastic-plastic analyses were performed with regard to twelve silicon particles including the fractured and intact particles detected by the chronological CT observation. By using the image-based modeling technique, the interested particle was embedded in the finite element model along with the surrounding particles as they were in the specimen. The material properties of silicon phase and aluminum matrix were identified by the nanoindentation tests. Ten cycles of loading by the uniform stress which was equivalent to the load in the fatigue test was applied to the finite element model, and the stress, strain and their cyclic response around the silicon particles were simulated. The morphology analysis was also carried out for the interested particles, and the geometrical parameters affecting the particle fracture were examined. By comparing the results of fractured and intact particles, we found that there were some geometrical conditions for the fracture of silicon particles, and a certain magnitude of hydrostatic stress was required to break the particles.