scholarly journals Stereoscopic three-dimensional (3D) slit-lamp photography using a compact 3D digital camera

2021 ◽  
Vol 69 (5) ◽  
pp. 1303
Author(s):  
Omar Solyman ◽  
Meleha Ahmad ◽  
Karun Arora ◽  
AmandaD Henderson ◽  
Andrew Carey
Keyword(s):  
Three Dimensional ◽  
Digital Camera ◽  
Slit Lamp

scholarly journals Application of 3D Image Technology in Motor and Sensory Nerve Classification

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Na Liu
Keyword(s):  
Peroneal Nerve ◽  
Three Dimensional ◽  
Sensory Nerve ◽  
Digital Camera ◽  
Histochemical Staining ◽  
Dimensional Structure ◽  
3D Image ◽  
Three Dimensional Reconstruction ◽  
Camera System ◽  
Dimensional Reconstruction

Objective. To explore the application of 3D image technology in motor and sensory nerve classification. Methods. A total of 200 sections of the 5cm-long popliteal fossa peroneal nerve from adult volunteers were cut and frozen. The slices were 10 m thick, and the interval between the slices was 0.25 mm. Acetylcholinesterase histochemical staining was used to observe the changes of nerve bundles under the microscope. The stained sections were transformed into digital images by the digital camera system, and the images were stitched to obtain a two-dimensional panoramic image 100 times magnified. The properties of the functional bundles were manually judged. Using Amira 3.1 three‐dimensional reconstruction software to realize the three-dimensional reconstruction and visualization of nerve can not only accurately perceive the complex three-dimensional surface structure of nerve, but also arbitrarily display, rotate, scale, and segment the three-dimensional structure inside nerve, and carry out three-dimensional measurement in time. It has made preliminary achievements in brachial plexus, lumbosacral plexus, neural stem functional bundle (group), and intramuscular nerve routing and distribution, including the regeneration process of sensory nerve and three-dimensional reconstruction and visualization of composite tissue containing sensory nerve. Conclusion. Based on histology and computer technology, the functional band of short peroneal nerve can be reconstructed in 3D, which provides a feasible basis for the three-dimensional reconstruction of the functional band of the long peripheral nerve.

The efficacy of telemedicine for ophthalmology triage by a general practitioner

2005 ◽  
Vol 11 (1_suppl) ◽  
pp. 83-85 ◽  
Author(s):  
Alexandre Chater Taleb ◽  
György M Böhm ◽  
Marcos Avila ◽  
Chao Lung Wen
Keyword(s):  
General Practitioner ◽  
Digital Camera ◽  
Brazilian Population ◽  
Slit Lamp ◽  
Face To Face ◽  
Eye Disorders

Although there are enough ophthalmologists for the Brazilian population, they are not evenly distributed throughout the country. Tele-ophthalmology may therefore be a useful tool. We have examined the feasibility of ophthalmology triage, performed by a general practitioner (GP) with remote support from an ophthalmologist. Forty patients with a variety of external and internal eye disorders were examined by the GP and also reassessed by an ophthalmologist, face to face, and then remotely by another ophthalmologist. There was agreement in 95% of the diagnoses between face-to-face and distant evaluation. The use of a digital camera and slit-lamp allowed greater accuracy of telediagnosis than the use of a digital camera alone. The GP would have referred 36 patients to an ophthalmologist, while both the local and the remote ophthalmologist saw the need for referral in 31 cases, i.e. assessment by tele-ophthalmology resulted in a 14% decrease in referrals. GP triage therefore appears to be feasible after appropriate training.

Multi-perspective measurement of yarn hairiness using mirrored images

2016 ◽  
Vol 88 (6) ◽  
pp. 621-629 ◽  
Author(s):  
Lei Wang ◽  
Bugao Xu ◽  
Weidong Gao
Keyword(s):  
3D Model ◽  
Three Dimensional ◽  
Digital Camera ◽  
3D Measurement ◽  
Multiple Perspectives ◽  
Multiple Images ◽  
Image Processing Techniques ◽  
Yarn Hairiness ◽  
Processing Techniques ◽  
Planar Mirrors

Most photoelectric and imaging methods for yarn hairiness measurements often provide underestimated data of hairy fibers measured from light projection, which ignores the spatial orientations and shapes of protruding fibers. In this project, a three-dimensional (3D) system was developed to detect hairy fibers from multiple perspectives and to reconstruct a 3D model for the yarn that permits fibers to be traced spatially. The system utilized two angled planar mirrors to view a yarn from five different perspectives simultaneously, and a digital camera to capture the multiple images in one panoramic picture. The image-processing techniques were used to dissect the panoramic picture into five sub-images containing separate views of the yarn, and to segment the sub-images to obtain yarn silhouettes showing the edges of the yarn and hairy fibers. A 3D model of the yarn could be built by merging the five silhouettes with the angles defined by the scene geometry of the dual mirrors. From the 3D model, hairy fibers protruding from the yarn core could be traced in the space for accurate length measurements. The system represents a simple and practical solution for the 3D measurement of yarn hairiness.

scholarly journals Facial Edema Evaluation Using Digital Image Processing

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
A. E. Villafuerte-Nuñez ◽  
A. C. Téllez-Anguiano ◽  
O. Hernández-Díaz ◽  
R. Rodríguez-Vera ◽  
J. A. Gutiérrez-Gnecchi ◽  
...  
Keyword(s):  
Image Processing ◽  
Three Dimensional ◽  
Third Molar ◽  
Digital Camera ◽  
Pain Model ◽  
Temperature Changes ◽  
The Us ◽  
Thermographic Camera ◽  
Facial Edema ◽  
Inflammatory Drugs

The main objective of the facial edema evaluation is providing the needed information to determine the effectiveness of the anti-inflammatory drugs in development. This paper presents a system that measures the four main variables present in facial edemas: trismus, blush (coloration), temperature, and inflammation. Measurements are obtained by using image processing and the combination of different devices such as a projector, a PC, a digital camera, a thermographic camera, and a cephalostat. Data analysis and processing are performed using MATLAB. Facial inflammation is measured by comparing three-dimensional reconstructions of inflammatory variations using the fringe projection technique. Trismus is measured by converting pixels to centimeters in a digitally obtained image of an open mouth. Blushing changes are measured by obtaining and comparing the RGB histograms from facial edema images at different times. Finally, temperature changes are measured using a thermographic camera. Some tests using controlled measurements of every variable are presented in this paper. The results allow evaluating the measurement system before its use in a real test, using the pain model approved by the US Food and Drug Administration (FDA), which consists in extracting the third molar to generate the facial edema.

Three-dimensional Reconstruction of Functional Fascicular Groups inside a Segment of Common Peroneal Nerve

2009 ◽  
Vol 24 (1_suppl) ◽  
pp. 100-112 ◽  
Author(s):  
Yi Zhang ◽  
Jian Qi ◽  
Xiaolin Liu ◽  
Zuo Xiong ◽  
Shengjie Li ◽  
...  
Keyword(s):  
Peripheral Nerve ◽  
3D Reconstruction ◽  
Peroneal Nerve ◽  
Three Dimensional ◽  
Digital Camera ◽  
Common Peroneal Nerve ◽  
Histochemical Staining ◽  
Recombination Processes ◽  
Dimensional Reconstruction ◽  
Reconstruction Software

The virtual human plan has been the hot point of recent research. The objective of this study is to explore the possibility of three-dimensional (3D) reconstruction of functional fascicular groups inside short segmental peripheral nerve. A 5 cm length of common peroneal nerve was horizontally sliced at 0.25 mm intervals, and each section was stained with acetycholinesterase histochemical staining. The 2D panorama images were acquired by high-resolution digital camera under 100 x microscope and mosaic software; different functional fascicular groups were distinguished and marked. The topographic database was then matched using image processing software, through the 3D reconstruction achieved using 3D reconstruction software (Amira 3.1). The reconstructed 3D images could be rotated or zoomed in any direction and the intercross and recombination processes of nerve bundles could be observed. Based on the serial histological sections and computer technology, the 3D microstructure of short segmental peripheral nerve functional fascicular groups was reconstructed. These results provide the possibility of 3D reconstruction of long segmental peripheral nerve functional fascicular groups.

scholarly journals Applicability of the photogrammetry technique to determine the volume and the bulk density of small soil aggregates

Soil Research ◽  
2016 ◽  
Vol 54 (3) ◽  
pp. 354 ◽  
Author(s):  
D. Moret-Fernández ◽  
B. Latorre ◽  
C. Peña ◽  
C. González-Cebollada ◽  
M. V. López
Keyword(s):  
Strong Correlation ◽  
General Trend ◽  
Conservation Tillage ◽  
Soil Aggregates ◽  
Three Dimensional ◽  
Digital Camera ◽  
Aggregate Size ◽  
Soil Disturbance ◽  
The Relationship ◽  
Dimensional Surface

Aggregate density (ρ) is defined as the relationship between the mass and the volume occupied by an aggregate. Previous studies have characterised ρ on large to medium-sized soil aggregates (>4 mm diameter); however, little information is available for smaller aggregates (<4 mm). The objective of this study was to test the viability of the photogrammetry (PHM) technique to determine the volume and subsequent ρ of small soil aggregates (1–8 mm diameter). The method uses a standard digital camera that photographs a rotating aggregate and reconstructs its three-dimensional surface and the corresponding volume. To validate the method, the volume estimated with PHM on rough stones of different sizes (1–16 mm diameter) was compared with the corresponding volume measured by the Archimedes’ principle. The method was tested on soil aggregates 1–8 mm in diameter, collected from two sites under conventional and conservation tillage treatments. The strong correlation (R2 > 0.99, P < 0.0001) between the volumes estimated on rough stones with the PHM and Archimedes methods demonstrates that this technique can be satisfactorily used to estimate the volume and, consequently, the ρ of small soil aggregates. The results showed an increase in ρ with decreasing aggregate size. A general trend of increasing ρ with the degree of soil disturbance by tillage was also observed.

Research of Binocular Positioning Mathematical Model Based on the Least Square Method

2011 ◽  
Vol 50-51 ◽  
pp. 473-477 ◽  
Author(s):  
Chun Feng Liu ◽  
Xiao Li Meng ◽  
Huan Cheng Zhang
Keyword(s):  
Relative Position ◽  
Three Dimensional ◽  
Digital Camera ◽  
Least Square Method ◽  
Absolute Error ◽  
Least Square ◽  
Specific Data ◽  
Centroid Algorithm ◽  
Three Dimensional Coordinate ◽  
The Relationship

By giving a centroid algorithm to extract pixel coordinates of each circle in the center of a circle under the coordinates, through the coordinate transformation the image coordinates can be obtained. Based on the data obtained from above to verify the model, from the specific data of the relative error, absolute error and error propagation theory to discuss the algorithm accuracy and stability. Finally using the least square method, according to the mean square error criteria for the establishment of a minimum of three-dimensional coordinate system fixed relative position of two cameras, binocular positioning mathematical models and by discussing the nature of matrix and the relationship between the relative position of the camera to calibrate the binocular digital camera.

scholarly journals UAV-BASED 3D VIRTUAL TOUR CREATION

2021 ◽  
Vol XLVI-4/W5-2021 ◽  
pp. 493-499
Author(s):  
U. G. Sefercik ◽  
T. Kavzoglu ◽  
M. Nazar ◽  
C. Atalay ◽  
M. Madak
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Digital Camera ◽  
Optimal Number ◽  
Virtual Tour ◽  
Artificial Environment ◽  
Fast Processing ◽  
Game Engines ◽  
Occlusion Culling ◽  
Mesh Models

Abstract. Lately, improvements in game engines have increased the interest in virtual reality (VR) technologies, that engages users with an artificial environment, and have led to the adoption of VR systems to display geospatial data. Because of the ongoing COVID-19 pandemic, and thus the necessity to stay at home, VR tours became very popular. In this paper, we tried to create a three-dimensional (3D) virtual tour for Gebze Technical University (GTU) Southern Campus by transferring high-resolution unmanned air vehicle (UAV) data into a virtual domain. UAV data is preferred in various applications because of its high spatial resolution, low cost and fast processing time. In this application, the study area was captured from different modes and altitudes of UAV flights with a minimum ground sampling distance (GSD) of 2.18 cm using a 20 MP digital camera. The UAV data was processed in Structure from Motion (SfM) based photogrammetric evaluation software Agisoft Metashape and high-quality 3D textured mesh models were generated. Image orientation was completed using an optimal number of ground control points (GCPs), and the geometric accuracy was calculated as ±8 mm (~0.4 pixels). To create the VR tour, UAV-based mesh models were transferred into the Unity game engine and optimization processes were carried out by applying occlusion culling and space subdivision algorithms. To improve the visualization, 3D object models such as trees, lighting poles and arbours were positioned on VR. Finally, textual metadata about buildings and a player with a first-person camera were added for an informative VR experience.

scholarly journals INTEGRATION OF GEODATA IN DOCUMENTING CASTLE RUINS

2016 ◽  
Vol XLI-B3 ◽  
pp. 345-349
Author(s):  
P. Delis ◽  
M. Wojtkowska ◽  
P. Nerc ◽  
I. Ewiak ◽  
A. Lada
Keyword(s):  
Laser Scanning ◽  
Three Dimensional ◽  
Digital Camera ◽  
Terrestrial Laser Scanning ◽  
Point Clouds ◽  
3D Models ◽  
Digital Imagery ◽  
Historical Structures ◽  
Three Dimensional Models ◽  
Different Sources

Textured three dimensional models are currently the one of the standard methods of representing the results of photogrammetric works. A realistic 3D model combines the geometrical relations between the structure’s elements with realistic textures of each of its elements. Data used to create 3D models of structures can be derived from many different sources. The most commonly used tool for documentation purposes, is a digital camera and nowadays terrestrial laser scanning (TLS). Integration of data acquired from different sources allows modelling and visualization of 3D models historical structures. Additional aspect of data integration is possibility of complementing of missing points for example in point clouds. The paper shows the possibility of integrating data from terrestrial laser scanning with digital imagery and an analysis of the accuracy of the presented methods. The paper describes results obtained from raw data consisting of a point cloud measured using terrestrial laser scanning acquired from a Leica ScanStation2 and digital imagery taken using a Kodak DCS Pro 14N camera. The studied structure is the ruins of the Ilza castle in Poland.

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