Complete 3D Reconstruction Research Articles

Virtual Simulation of Aerobics Movement Based on Vision

In aerobics, the motion state randomness of key feature points is great, so it is difficult to establish an accurate dynamic model for sports' shape base. Traditional 3D reconstruction algorithms use fixes shape base which hardly expresses the change parameters of complex movement and motion law of large-scale dynamic features, thereby leading to non-realistic reconstruction results. The paper proposes a new reconstruction algorithm for aerobics 3D motion images that corrects the neighborhood system of feature points by motion parameters until the parameter is stable to ensure accuracy and the stability of correction. The simulation results show that, the proposed algorithm avoids drawbacks of sports reconstruction results caused by the great randomness of aerobics' motion state, thereby complete 3D reconstruction for aerobics' motion images.

3D reconstruction methods for digital preservation of cultural heritage: A survey

3D reconstruction, refers to capturing and reproducing the shape and appearance of an arbitrary object or scene given depth and color information. This is a broad research area within the computer vision field involving many stages and still open problems. The digital preservation of cultural heritage is a specially challenging application of 3D reconstruction. Cultural heritage objects and sites greatly differ from each other and a maximized fidelity of the 3D reconstruction is a core requirement. The literature on this topic has substantially increased in the past years, mostly due to the variety of scenarios and the development of new depth sensing devices as well as techniques able to deal with this issue. In our search to develop a complete 3D reconstruction pipeline, we have comprehensively studied techniques related to this topic and divided the 3D digitization process in four major overviews: image acquisition, view registration, mesh integration and texture generation. We present the state-of-the-art approaches and challenges of each stage.

IMAGE-BASED SURVEYING AND MODELING OF THE UNPROTECTED ARCHITECTURAL HERITAGE – ST. RUDOLF'S CHURCH IN BANOSTOR

Abstract. The aim of this paper is to present image-based recording of the unprotected architectural heritage in threat and its advantages integrating different modeling methods. Considering the construction problems in unprotected buildings we applied variations of low-budget image-based 3D modeling reconstructions techniques and built the complete virtual 3D reconstruction of highly damaged church of St. Rudolph in Banostor. The resulting model reveals many construction and design details that can not be perceived by a simple observing. In this paper, the importance of integrating a variety of measuring and modeling methodologies in order to achieve digital reconstruction of the unapproachable ruined building is demonstrated. The paper describes survey techniques and workflow, focusing on advantages as well as problems and limitations of each method.

ORIENTATION AND DENSE RECONSTRUCTION OF UNORDERED TERRESTRIAL AND AERIAL WIDE BASELINE IMAGE SETS

Abstract. In this paper we present an approach for detailed and precise automatic dense 3D reconstruction using images from consumer cameras. The major difference between our approach and many others is that we focus on wide-baseline image sets. We have combined and improved several methods, particularly, least squares matching, RANSAC, scale-space maxima and bundle adjustment, for robust matching and parameter estimation. Point correspondences and the five-point algorithm lead to relative orientation. Due to our robust matching method it is possible to orient images under much more unfavorable conditions, for instance concerning illumination changes or scale differences, than for often used operators such as SIFT. For dense reconstruction, we use our orientation as input for Semiglobal Matching (SGM) resulting into dense depth images. The latter can be fused into a 2.5D model for eliminating the redundancy of the highly overlapping depth images. However, some applications require full 3D models. A solution to this problem is part of our current work, for which preliminary results are presented in this paper. With very small unmanned aerial systems (Micro UAS) it is possible to acquire images which have a perspective similar to terrestrial images and can thus be combined with them. Such a combination is useful for an almost complete 3D reconstruction of urban scenes. We have applied our approach to several hundred aerial and terrestrial images and have generated detailed 2.5D and 3D models of urban areas.

A novel approach for a complete 3D tooth reconstruction using only 3D crown data

Current methods to produce 3-dimensional complete tooth (enamel, dentin and pulp) models involve conversion from tomographic data. In the paper a novel approach to obtain the complete 3D reconstruction of a tooth starting from the only 3D crown information is described. Using as reference models, five human posterior molars derived from micro-computed tomography (CT) data, specific computer aided design (CAD) modeling procedures were developed to create, in a simplified way, the surfaces of enamel, dentin and pulp of the teeth, starting from the data of a molar acquired by a non-contact reverse engineering (RE) system. To evaluate the simplified model, finite element method (FEM) simulations were performed and compared. The results from FEM analysis confirm the general validity of the proposed approach. This method allows to generate an efficient complete 3D reconstruction of teeth with a good approximation of the shape, due to the small number of parameters to adjust, and requires little interaction from the user. The described method can be successfully adopted to generate detailed 3D CAD models of teeth starting only from the crown data, acquired by non-contact RE systems (structured-light scanners, laser scanners or intra-oral laser scanners). It could be quickly implemented for other dental or biomechanical applications without the use of more expensive CT and micro-CT.

Principal Component and Cluster Analysis of Layer V Pyramidal Cells in Visual and Non-Visual Cortical Areas Projecting to the Primary Visual Cortex of the Mouse

The long-distance corticocortical connections between visual and nonvisual sensory areas that arise from pyramidal neurons located within layer V can be considered as a subpopulation of feedback connections. The purpose of the present study is to determine if layer V pyramidal neurons from visual and nonvisual sensory cortical areas that project onto the visual cortex (V1) constitute a homogeneous population of cells. Additionally, we ask whether dendritic arborization relates to the target, the sensory modality, the hierarchical level, or laterality of the source cortical area. Complete 3D reconstructions of dendritic arbors of retrogradely labeled layer V pyramidal neurons were performed for neurons of the primary auditory (A1) and somatosensory (S1) cortices and from the lateral (V2L) and medial (V2M) parts of the secondary visual cortices of both hemispheres. The morphological parameters extracted from these reconstructions were subjected to principal component analysis (PCA) and cluster analysis. The PCA showed that neurons are distributed within a continuous range of morphologies and do not form discrete groups. Nevertheless, the cluster analysis defines neuronal groups that share similar features. Each cortical area includes neurons belonging to several clusters. We suggest that layer V feedback connections within a single cortical area comprise several cell types.

Cluster self-organization of inorganic crystal-forming systems: Templated nanocluster precursors and self-assembly of framework MT structures of A/B,Zr silicates (A = Na, K; B = Ca, Sr)

The basic concepts that are used to describe crystallization as a phenomenon of the hierarchical (cluster) self-organization of a chemical system are considered. The templation of theoretically possible nan-ocluster precursors composed of M octahedra and T tetrahedra by atoms of (A) alkaline and (B) alkaline earth metals is considered for the first time. A relationship between the A/B,M,T composition of templated nanocluster precursors with the composition of A/B,M silicates is established. The model that is developed is used to search for nanocluster precursors in framework MT structures of A/B,Zr silicates. Computer methods (TOPOS 4.0 program package) were used to perform complete 3D reconstruction of the self-assembly of all (four) structural types of A/B,Zr silicates (A = Na, K; B = Ca, Sr) with frameworks of the MT2O7 type: nan-ocluster precursor S30-primary chain S31-microlayer S32-microframework S33. The invariant type of mono-cyclic nanocluster precursor M2T4 (with the point symmetries \(\bar 1\) and 2), stabilized by one or two template cations (A and B), is determined. Bifurcations of the paths of evolution at the S31 level (structural branching point) are established for the self-assembly of the following frameworks: MT-1 in CaZrSi2O7 (gittinsite, C2), MT-2 in SrZrSi2O7 (P21/c); MT-3 in Na2ZrSi2O7 (parakeldyshite,), K2ZrSi2O7 (khibinskite, P21/b), and K2ZrGe2O7 (C2/c); and MT-4 in Na2ZrSi2O7 (H2O)(C2/c), Na3ScSi2O7 (Pbnm), and K3ScSi2O7 (P63/mmc).

Cluster self-organization of intermetallic systems: Nanocluster precursors (i-K8, i-K6, K4) and self-assembly of crystal structures Ir8Mg58(cF396), Ir7Mg44(cF408), and Ir6Mg26 (hR96)

Suprapolyhedral cluster precursors Kn with a hierarchical structure (with the number of polyhedra n = 4, 6, 8) have been derived and their topological representation as bichromatic graphs has been performed. With the use of computer methods (the TOPOS program package), combinatorial-topological analysis of icosahedral monster structures of close compositions Ir8Mg58 (cF396, F\( \bar 4 \)3m, V = 8139 A3) and Ir7Mg44 (cF408, F\( \bar 4 \)3m, V = 8117 A3) has been performed. Suprapolyhedral nanoclusters consisting of eight and six Ir icosahedra (nanoclusters i-K8 and i-K6 comprising 86 and 50 atoms) have been identified by the method of complete decomposition of the 3D factor graph of crystal structures into cluster substructures in Ir7Mg44. In Ir8Mg58, the i-K8 nanocluster is retained, whereas the i-K6 cluster is substituted by the K4 nanocluster composed of four Ir polyhedra with CN = 9 comprising 34 atoms. Complete 3D reconstruction of the self-assembly mechanism of crystal structure has been carried out by the scheme nanocluster precursor-primary chain-microlayer-microframework. It has been demonstrated that the voids in the Ir8Mg58 and Ir7Mg44 frameworks accommodate tetrahedral cluster spacers T-Mg(Mg4) and T-Mg4, respectively. The Ir6Mg26 structure (hR96, R\( \bar 3 \)c, V = 1890 A3) is made of the suprapolyhedral cluster K6 formed by six Ir polyhedra with CN = 11 and comprising 50 atoms; in this case, the structure contains no cluster spacers. In all structures, nanoclusters retain their own symmetry (\( \bar 4 \)3m for i-K8, i-K6, and K4 and \( \bar 3 \) for K6).

Modeling of self-organization of silicate systems: Precursor nanoclusters and self-assembly of Na3MSi3O9 (M = Y, Eu-Lu; oP256) crystal structures producing two interpenetrating diamond-type frameworks

In the M-T-O model system (M is a polyvalent metal with CN ≥ 4; T is Si), cyclic clusters have been deduced as graphs in the T/M range from one to three. The case is considered when monocyclic cluster M2T2 is modified by T-tetrahedra that form diortho groups T2. The M sites of the cluster have either topologically different local MT structures (four types) or identical local MT structures (two types). The cluster types for T/M = 3 obtained by modeling were used in analysis of one of the most complicated types of silicate crystal structures Na3MSi3O9 (M = Y; Eu-Lu; T/M = 3) with the Pearson index oP256 and 64 independent atoms. The TOPOS program package was used to carry out the complete 3D reconstruction of the self-assembly of the crystal structure: suprapolyhedral precursor nanocluster → primary chain → microlayer → microframework (supraprecursor) → ... three-dimensional framework. The calculation of the coordination sequences of site atoms in the 3D network of the MT framework MT3O9 revealed topological symmetry related to a three-dimensional separation of the framework into two interpenetrating frameworks. Each framework structure is generated by topologically equivalent cyclic precursor clusters Na2M2T6 consisting of two YO6 octahedra comprising three diortho groups Si2O7 and two Na atoms located above and below the ring center. The 3D graphs characterizing the connectivity of the centers of crystallographically equivalent clusters in the frameworks correspond to diamond-type networks.

Real-time 3D registration using GPU

3D registration is a computer vision technique of aligning multi-view range images with respect to a reference coordinate system. Aligning range images is an important but time-consuming task for complete 3D reconstruction. In this paper, we propose a real-time 3D registration technique by employing the computing power of graphic processing unit (GPU). A point-to-plane 3D registration technique is completely implemented using CUDA, the up-to-date GPU programming technique. Using a hand-held stereo-vision sensor, we apply the proposed technique to real-time 3D scanning of real objects. Registration of a pair of range images, whose resolution is 320 × 240, takes about 60 ms. 3D scanning results and processing time analysis are shown in experiments. To compare the proposed GPU-based 3D registration with other CPU-based techniques, 3D models of a reference object are reconstructed. Reconstruction results of three different techniques in eight different scanning speed are evaluated.

Feasibility of Contactless 3D Optical Measurement for the Analysis of Bone and Soft Tissue Lesions: New Technologies and Perspectives in Forensic Sciences

In forensic pathology and anthropology, a correct analysis of lesions on soft tissues and bones is of the utmost importance, in order to verify the cause and manner of death. Photographs, videos, and photogrammetry may be an optimal manner of immortalizing a lesion, both on cadavers and skeletal remains; however, none of these can supply a detailed three-dimensional (3D) modeling of the lesion. Up to now, only the use of casts has given us the possibility of studying deep lesions such as saw marks with an accurate and complete 3D reconstruction of bone structure. The present study aims at verifying the applicability of 3D optical contactless measurement for the accurate recording of soft tissue and bone lesions, in order to develop a unique and precise method of registering and analyzing lesions, both in forensic pathology and anthropology. Three cases were analyzed: the first, a car accident with blunt force skin injuries; the second, a murder with blunt force injury to the head applied with a metal rod; the third, a series of sharp force knife and saw lesions on bone. Results confirm that 3D optical digitizing technology is a crucial tool in the immortalization of wound morphology in the medico-legal context even on "difficult" substrates such as cut marks and saw marks on bone.

Cluster self-organization of Na-TR-Ge-O-H (TR = La-Lu, Y, and Sc) germanate systems: Suprapolyhedral precursor clusters and self-assembly of Na2Pr6Ge8O26, Na4Sc2Ge4O13, and Na5ScGe4O12 crystal structures

In an M-T-O model system (M is a polyvalent metal; T = Ge or Si), we consider initial stages of formation of cyclic MT clusters and the mechanism of their modification by T tetrahedra. The polyhedron ratio T/M in clusters increases progressively during modeling from one in M2T2 to two (M2T2 + 2T = M2T4), three (M2T2 + 2T2 = M2T6), and four (M2T2 + 2T + 2T2 = M2T8). These types of clusters were used to find precursor clusters for T-condensed structures of Na2Pr6Ge8O26, Na4Sc2Ge4O13, and Na5ScGe4O12. The TOPOS program package was used to carry out the complete 3D reconstruction of the self-assembly of Na,TR germanates: precursor cluster → primary chain → microlayer → microframework (supraprecursor) → ... framework. In all structures, as previously in six orthotetrahedral Na,TR germanate structures, the basic invariant type of four-polyhedral cyclic precursor cluster M2T2 was identified; this cluster is built of TR polyhedra, with CN = 6 or 7, linked via orthotetrahedra. The features of the generation of a Ge radical were considered in the form of a Ge2O7 chain and a Ge4O12 ring in various layers of the Na2Pr6Ge8O26 composite structure, a Ge4O13 chain in Na4Sc2Ge4O13, and a Ge12O36 ring in the Na5ScGe4O12 superionic conductor.

Fluid in Video: Augmenting Real Video with Simulated Fluids

AbstractWe present a technique for coupling simulated fluid phenomena that interact with real dynamic scenes captured as a binocular video sequence. We first process the binocular video sequence to obtain a complete 3D reconstruction of the scene, including velocity information. We use stereo for the visible parts of 3D geometry and surface completion to fill the missing regions. We then perform fluid simulation within a 3D domain that contains the object, enabling one‐way coupling from the video to the fluid. In order to maintain temporal consistency of the reconstructed scene and the animated fluid across frames, we develop a geometry tracking algorithm that combines optic flow and depth information with a novel technique for “velocity completion”. The velocity completion technique uses local rigidity constraints to hypothesize a motion field for the entire 3D shape, which is then used to propagate and filter the reconstructed shape over time. This approach not only generates smoothly varying geometry across time, but also simultaneously provides the necessary boundary conditions for one‐way coupling between the dynamic geometry and the simulated fluid. Finally, we employ a GPU based scheme for rendering the synthetic fluid in the real video, taking refraction and scene texture into account.

Transmitted light brightfield mosaic microscopy for three-dimensional tracing of single neuron morphology

A fundamental challenge in neuroscience is the determination of the three-dimensional (3D) morphology of neurons in the cortex. Here we describe a semiautomated method to trace single biocytin-filled neurons using a transmitted light brightfield microscope. The method includes 3D tracing of dendritic trees and axonal arbors from image stacks of serial 100-microm-thick tangential brain sections. Key functionalities include mosaic scanning and optical sectioning, high-resolution image restoration, and fast, parallel computing for neuron tracing. The mosaic technique compensates for the limited field of view at high magnification, allowing the acquisition of high-resolution image stacks on a scale of millimeters. The image restoration by deconvolution is based on experimentally verified assumptions about the optical system. Restoration yields a significant improvement of signal-to-noise ratio and resolution of neuronal structures in the image stack. Application of local threshold and thinning filters result in a 3D graph representation of dendrites and axons in a section. The reconstructed branches are then manually edited and aligned. Branches from adjacent sections are spliced, resulting in a complete 3D reconstruction of a neuron. A comparison with 3D reconstructions from manually traced neurons shows that the semiautomated system is a fast and reliable alternative to the manual tracing systems currently available.

Amyloid deposition in the hippocampus and entorhinal cortex: quantitative analysis of a transgenic mouse model.

Various transgenic mouse models of Alzheimer's disease (AD) have been developed that overexpress mutant forms of amyloid precursor protein in an effort to elucidate more fully the potential role of beta-amyloid (A beta) in the etiopathogenesis of the disease. The present study represents the first complete 3D reconstruction of A beta in the hippocampus and entorhinal cortex of PDAPP transgenic mice. A beta deposits were detected by immunostaining and thioflavin fluorescence, and quantified by using high-throughput digital image acquisition and analysis. Quantitative analysis of amyloid load in hippocampal subfields showed a dramatic increase between 12 and 15 months of age, with little or no earlier detectable deposition. Three-dimensional reconstruction in the oldest brains visualized previously unrecognized sheets of A beta coursing through the hippocampus and cerebral cortex. In contrast with previous hypotheses, compact plaques form before significant deposition of diffuse A beta, suggesting that different mechanisms are involved in the deposition of diffuse amyloid and the aggregation into plaques. The dentate gyrus was the hippocampal subfield with the greatest amyloid burden. Sublaminar distribution of A beta in the dentate gyrus correlated most closely with the termination of afferent projections from the lateral entorhinal cortex, mirroring the selective vulnerability of this circuit in human AD. This detailed temporal and spatial analysis of A beta and compact amyloid deposition suggests that specific corticocortical circuits express selective, but late, vulnerability to the pathognomonic markers of amyloid deposition, and can provide a basis for detecting prior vulnerability factors.

Post-Mortem Three-Dimensional Reconstruction of the Entire Coronary Arterial Circulation Using Electron-Beam Computed Tomography

A 50-year-old man died suddenly while exercising on a treadmill at a local health club. He had no known previous cardiac history. During autopsy, a radio-opaque silicone compound was injected into the coronary arteries. The explanted heart was then imaged by electron-beam computed tomography (EBCT) using 3-mm slices. A complete 3D reconstruction was then obtained …

Three-dimensional reconstruction of the membranous vestibular labyrinth in the toadfish, Opsanus tau

Membranous vestibular labyrinths from the oyster toadfish, Opsanus tau, were fixed, dissected from the animal, stained, and embedded in rectangular blocks of clear histological resin. Photomicrographs of complete embedded labyrinths were taken from six orthogonal directions and used to construct three-dimensional (3D) geometrical models of the semicircular canals, ampullae, utricular vestibule and common crus. Membranous ducts and ampullae were modeled using a set of cross-sectional elliptical curves laced together to generate curved tubular models of each structure. The ensemble of these curved tubes was used to generate a complete 3D reconstruction of the outside surface of the membranous labyrinth. When viewed from six orthogonal directions, reconstructions closely matched the embedded tissue. Dimensions of the reconstruction and histological sections were compared to measurements of fresh tissue taken from the same animals prior to fixation and used to correct the reconstructions for tissue shrinkage. Results provide estimates of the endolymphatic volumes, local cross-sectional areas and elliptical eccentricities as well as 3D orientations of the geometric canal planes relative to the skull. Ten micrometer histological sections of the material were also prepared to measure wall thickness in various regions of the labyrinth.