Photogrammetry Method Research Articles

Remote sensing and nuclear techniques for high-resolution mapping and quantification of gully erosion in the highly erodible area of the Malčanska River Basin, Eastern Serbia

Gully erosion leads to the formation of deep and wide channels that increase the risk of soil loss, flooding, and water pollution. In addition, this process reduces the productivity and viability of agricultural land and natural ecosystems. Preventing gully erosion is critical for maintaining ecological balance and preserving natural resources in certain areas. This paper presents a methodology integrating remote sensing and nuclear techniques to study gully erosion. The morphometric characterization of gullies using 360-degree camera photogrammetry was introduced as a new method in erosion research. This approach aims to investigate the suitability of unmanned aerial vehicle and terrestrial photogrammetry for modeling gullies, to study the variability of erosion processes in gullies at a small scale, and to compare the differences in erosion intensity between nearby gullies. The study's objectives include identifying the effective and economical method for gullies monitoring and providing a starting point for controlling and safeguarding gullies. Mainly erosion process was detected in the studied gullies, while deposition was identified at only 2 out of 39 sampling locations. The results showed an average soil redistribution rate of 16.2 t ha−1 yr−1 and coefficients of variation of 32%, 59%, and 91% for three investigated gullies. It was determined that aerial photogrammetry methods were not practical under the conditions prevailing in the study area. Highly detailed 3D models of the gullies were created using 360-degree photogrammetry. It was confirmed that the micro-relief obtained by photogrammetric modeling is an essential contribution to erosion research. The 360-degree camera photogrammetry serves as a reliable tool for analyzing the morphology of gullies and, in perspective, tracking changes in gully systems over time or monitoring the effectiveness of the applied protection measures.

Photogrammetry for 3D Reconstruction of Objects: Effects of Geometry, Texture and Photographing

Today, the use of 3D scanning methods is increasing in a wide range of industries from biomedical to game production. The photogrammetry method is in demand by 3D scanning users due to its portability, photorealistic textured modeling, and low cost. Scanned objects vary according to industries and can have various materials, geometries and textures. In order to better benefit from the advantages of the photogrammetry method, it is necessary to know the response of the method against different parameters. Unlike the studies in the literature, in this study, many objects with various geometries, different materials and textures were reconstructed and evaluated by using the same equipment and workflow in the same environment, and thus a fair evaluation was performed for various factors affecting the reconstruction process. In this context, 24 differently shaped objects with metal, fabric, plastic, wood, glass, ceramic and organic textures were reconstructed. A comprehensive evaluation was conducted on the solid and textured models generated from the objects. In addition to the effects of object geometry, texture properties, photo shooting angle and distance, it also sought answers to questions about factors affecting the accuracy and mesh quality of the 3D models. In this study, it is possible to find some recent specific results and validated general results together related to photogrammetric modeling.

Calibration of stereo-digital image correlation for large field of view measurement based on photogrammetry

Calibration of a stereo-digital image correlation (stereo-DIC) system is essential for three-dimensional (3D) shape and deformation measurement. Although the traditional planar calibration method is flexible in most application scenarios, it still has difficulties in large field of view (FOV) calibration due to the limited size of calibration board. In this paper, a stereo-vision calibration method is proposed for large FOV measurement based on the close-range photogrammetry. Specifically, a certain number of coded targets are first arranged in the area to be measured. Then, the left and right cameras are used to capture images at the calibration and measurement positions. With these images, accurate camera intrinsic parameters can be obtained by close-range photogrammetry methods through encoded targets. The extrinsic parameters can be obtained by the 3D coordinates of these corresponding points and further optimized using corresponding points obtained from both coded targets and speckle patterns. Laboratory experiments with field-of-view ranges of 25 cm by 25 cm and 2.8 m by 2.8 m demonstrate that this method can obtain precise calibration parameters and has good deformation measurement accuracy. Compared to traditional planar calibration methods, this method does not require high-quality or large-sized calibration objects, and all parameters can be calibrated on-site. A large shaking table experiment demonstrated the potential of this method in the field of engineering measurements.

PHOTOGRAMMETRIC MODEL OPTIMIZATION IN DIGITALIZATION OF ARCHITECTURAL HERITAGE: YEDIKULE FORTRESS

Abstract. The idea of "digitalization of architectural heritage" has recently gained prominence to represent architectural and historical assets. With all these potentials, this study aims to create optimized models that can be used in serious gaming environments by presenting a method of photogrammetry. As a case study, Yedikule Fortress and its surroundings, which have a multi-layered structure that includes many cultural aspects such as Byzantine, Ottoman, and Republican periods in the historical process, have been studied within the scope of digitizing the architectural heritage to create an optimized model for gaming environments. The study was methodologically constructed in three phases: Photogrammetry, polygon modeling, and low poly/high poly baking process. The fortress and its surroundings are modeled using a high-detail point cloud and a high-poly mesh using aerial photogrammetry. The high-poly model was taken as a reference and transferred into a low-poly model as a mesh map, texture, and light characteristics. This allowed the high poly model to operate more efficiently and effectively in game engines. As a result, the study created a detailed and optimized model for the game engines to produce serious games specific to light and texture data, to be used on devices that support mixed reality (MR) technologies.

BIM AND UAV PHOTOGRAMMETRY FOR SPATIAL STRUCTURES SUSTAINABILITY INVENTORY

Abstract. The paper describes the basic concept of the integration between UAV surveying results and BIM. As a case study, it was considered the large spatial shell that served as a hangar for the Antonov An-225 Mriya, the largest in the world strategic cargo aircraft with a maximum take-off weight of 640 tons. Due to an explosion inside, the hangar and aircraft were significantly damaged. The key point of the study is the damage estimation by analysis and modeling of this unique engineering structure. The study has included several steps: hangar structure documentation (before damage), UAV surveying of the hangar (for ongoing condition estimation), terrestrial measurements for the control, and integration of 3D models inside BIM for structural analysis. Deploying the UAV allowed us to generate detailed 3D models of the hangar by means of photogrammetry and computer vision methods. The inclusion of the field geodetic measurements into the processing made it possible to increase significantly positioning accuracy of the results to the sub-centimeter level and served as a ground truth for the models obtained based on UAV sensors data. The results proved the feasibility of BIM and UAV photogrammetry for the hangar stability model development and practical verification based on geospatial and structural engineering data.

Research on the close-range photogrammetry accuracy of 3D digital interactive platform of Hunan intangible cultural heritage

Abstract This paper designed a three-dimensional digital interactive platform, which takes power supply module, image data acquisition module, control module, data transmission module and ESAM module as the main hardware and makes it feasible to realize power supply transmission, multiple data acquisition, platform process control, data transmission, data encryption and decryption, and identity authentication. Then, through relative orientation element calculation, model point coordinate calculation, relative orientation model proportion coefficient calculation, relative orientation model deformation accuracy calculation, and relative orientation accuracy calculation, this paper realized the relative control of close-range photogrammetry, improving the accuracy of close-range photogrammetry. The results show that the relative control method of close-range photogrammetry studied in this paper can increase the relative accuracy from 319 to 769 and improve the average value of the relative orientation model deformation accuracy from 0.4282 to 0.5938. In addition, in performance analysis, the response time of the platform is 0.32s, the accuracy of close-range photogrammetry is 96.3%, and the comprehensiveness of data detection is 94.37%. Therefore, it is concluded that using the method proposed in this paper, the relative orientation model deformation accuracy is increased, the accuracy of close-range photogrammetry is the highest, and the data detection is more comprehensive.

Study of karst manifestations in Solotvyno based on aerial photography from a UAV

Abstract This article is devoted to the study of surface karst manifestations on the territory of inactive salt mines of Solotvyno, Transcarpathian region, Ukraine. The historical development of the salt mine from the moment of the creation of the first mine (the end of the 18th century) to the present is considered. Based on the results of previously published studies, monitoring of karst manifestations from 2010 to 2020 was implemented. The last stage of monitoring in 2021 was the aerial survey of the territory obtained by the Arrow UAV using the Sony QX1 camera. Pix4Dmapper software was used for image processing. The aim of the work is to estimate the scale of destructive geological processes by the method of photogrammetry. During the execution of the work, the methods of processing materials of aerial photography, analysis of developments in the direction of photogrammetry were applied. As a result of the study, the volume-planar characteristics of karst formations on the territory of Solotvyno were calculated using the photogrammetry method. This scientific work is relevant for assessing the scale of the development of degenerative geological processes on the territory of Ukraine, in particular within the Transcarpathian region. The practical significance of the obtained results lies in their application in order to ensure environmental monitoring. The results of the study can be used to predict the impact on economic and infrastructure objects, followed by the development of a plan of specific actions for prevention, localization and work with the consequences of man-made processes in the adjacent territory.

Comparison of Manual (2D) and Digital (3D) Methods in the Assessment of Simulated Facial Edema

An edema assessment following dental surgeries is essential to improving the dental surgeon's technique and, consequentially, patient comfort. Two-dimensional (2D) methods are limited in analyzing 3-dimensional (3D) surfaces. Currently, 3D methods are used to investigate postoperative swelling. However, there are no studies that directly compare 2D and 3D methods. The goal of this study is to directly compare 2D and 3D methods used in the assessment of postoperative edema. The investigators implemented a prospective, cross-sectional study with each subject serving as its own control. The sample was composed of dental student volunteers without facial deformities. The predictor variable is the method used to measure edema. After simulating edema, manual (2D) and digital (3D) techniques were used to measure edema. The manual method used direct facial perimeter measurements. The two digital methods were photogrammetry using a smartphone (iPhone 11, Apple Inc, Cupertino, California), and facial scanning with a smartphone application (Bellus3D FaceApp, Bellus3D Inc, Campbell, California) [3D measurements] MAIN OUTCOME VARIABLE: The coefficient of variation (CV) (CV=standard deviation /mean) was used to assess homogeneity of edema measurements. The Shapiro-Wilk and equal variance tests were applied to assess data homogeneity. Next, one-way analysis of variance was performed, followed by a correlation analysis. Finally, the data were submitted to Tukey's test. The statistical significance threshold was set at 5% (P<.05). The sample was composed of 20 subjects aged 18-38years. The CV showed higher values using the manual (2D) method (47%; 4.88%±2.99), compared with the photogrammetry method (18%; 8.55mm±1.52) and the smartphone application (21%; 8.97mm±1.93). A statistically significant difference was observed between the manual method values and those of the other two groups (P<.001). There was no difference between the facial scanning and photogrammetry groups (3D methods) (P=.778) CONCLUSION AND RELEVANCE: Both digital measuring methods (3D) demonstrated greater homogeneity than the manual method in analyzing facial distortions caused by the same swelling simulation. Therefore, it can be affirmed that digital methods may be more reliable that manual methods for assessing facial edema.

A quick and low-cost smartphone photogrammetry method for obtaining 3D particle size and shape

Reliable particle measurements are essential when investigating the size and shape of particles in various fields of study, including engineering geology. Common methods to determine the morphology of particles, such as 3D laser scanners, are typically expensive or require extensive preparation. Therefore, a setup-friendly, low-cost, and accurate approach is required. In this study, a practical Trick-Image-Capturing (TIC) method based on smartphone photogrammetry to obtain size and shape parameters of 3D coarse particles is proposed. The process of image acquisition and particle reconstruction of the TIC method is demonstrated. Then, the performance of the TIC method is comprehensively assessed under various conditions using a 3D laser scanner, including smartphone quality, particle shape, shooting method, and postprocessing software. An optimal setting of the TIC method is selected through the cloud-to-cloud distance. Finally, the size and shape parameters of 32 coarse particles using the TIC method are also evaluated. Results show that the optimum setup of the TIC method is using a smartphone camera with a resolution above 12 MP under the ICS mode with a 30° shooting angle with Metashape postprocessing software. The root mean square error (RMSE) of cloud-to-cloud distances and the average error ratios under the optimum setup are less than 0.075 mm and 3.5%, respectively. Due to its fast image capturing process, easy setup, and low cost, the TIC method is practical and we expect it to become one of popular methods of measuring 3D coarse particles.

The artistic aesthetic and cultural value orientation of 3D printing

Abstract For the current artwork, 3D printing design simulation technology has the disadvantage of low clarity and poor effect, which cannot effectively describe the designer's work. To this end, this paper investigates the artistic aesthetic and cultural value orientation of 3D printing. First, the 3D digitization work of the oil painting was carried out by using the multi-baseline photogrammetry method in photogrammetry technology. Then the non-measurement digital camera was checked for internal orientation elements, the control panel was photographed, and the internal orientation elements of the camera were measured using the spatial backward rendezvous solution method. Next, the digital image acquisition of the oil painting is carried out, and finally, the photos are sequentially introduced into the Lens photo multi-baseline photogrammetry system to generate the color point cloud model of the oil painting after performing the steps of homonymous point selection null-three matching and beam leveling. In order to enhance the visualization effect, the color point cloud model was used to generate a digital model of the TIN irregular triangular network to realize the 3D digitization of oil painting art. The results of the study show that the thickness of each layer obtained by UV inkjet printing of five types of inks: yellow, green, blue, black, and white is about 11.19 μm, 12.71 μm, 7.91 μm, 9.47 μm, and 13.12 μm, respectively. 3D printing technology for positive impact on art design needs to be recognized and respected, and the better development of related technologies can make the advantages and advancement of the technology itself more fully embodied.

UAV-based operational modal analysis method using improved homography-based perspective rectification method

In this paper, a new dynamic photogrammetry method using an unmanned aerial vehicle (UAV) is proposed and the UAV-based operational modal analysis method is established. The presented dynamic photogrammetry method can measure the dynamic displacements of structure using one or two cameras. However, it is difficult to use fixed cameras or handheld cameras to measure the dynamic responses for some outdoor structures, because it is hard to reach for measurement or maintenance sometimes. Therefore, UAV is an effective alternative and the homography-based perspective rectification method can be used to correct the UAV images. However, the presented methods use only four calibration points. Additionally, there is still obvious signal drift in the extracted dynamic responses. In this paper, a new time varying homography matrix, calculated using n calibration points, is proposed here for the first time to correct the perspective distortion for image at different time and the relative displacements are used to eliminate the influence of UAV in-plane motion. The influence analysis of UAV vibration and the method to eliminate the UAV vibration are the novelty of this paper. And then, the UAV-based operational modal analysis method is proposed. The proposed method is verified using a plane frame structure in laboratory. The results show that the proposed method can effectively eliminate the vibration of UAV and identify the structural modal parameters. Under the impulse excitation and white noise excitation, when the calibration points n is larger than 60, the relative errors of natural frequency and damping ratio are less than 0.4% and 5.45%, respectively. And the MAC values are all greater than 0.99. Meanwhile, the influence of the number of adopted calibration points on modal parameters identification is considered in the experiment and the advised value is given.

Looking behind occlusions: A study on amodal segmentation for robust on-tree apple fruit size estimation

The detection and sizing of fruits with computer vision methods is of interest because it provides relevant information to improve the management of orchard farming. However, the presence of partially occluded fruits limits the performance of existing methods, making reliable fruit sizing a challenging task. While previous fruit segmentation works limit segmentation to the visible region of fruits (known as modal segmentation), in this work we propose an amodal segmentation algorithm to predict the complete shape, which includes its visible and occluded regions. To do so, an end-to-end convolutional neural network (CNN) for simultaneous modal and amodal instance segmentation was implemented. The predicted amodal masks were used to estimate the fruit diameters in pixels. Modal masks were used to identify the visible region and measure the distance between the apples and the camera using the depth image. Finally, the fruit diameters in millimetres (mm) were computed by applying the pinhole camera model. The method was developed with a Fuji apple dataset consisting of 3925 RGB-D images acquired at different growth stages with a total of 15,335 annotated apples, and was subsequently tested in a case study to measure the diameter of Elstar apples at different growth stages. Fruit detection results showed an F1-score of 0.86 and the fruit diameter results reported a mean absolute error (MAE) of 4.5 mm and R2 = 0.80 irrespective of fruit visibility. Besides the diameter estimation, modal and amodal masks were used to automatically determine the percentage of visibility of measured apples. This feature was used as a confidence value, improving the diameter estimation to MAE = 2.93 mm and R2 = 0.91 when limiting the size estimation to fruits detected with a visibility higher than 60%. The main advantages of the present methodology are its robustness for measuring partially occluded fruits and the capability to determine the visibility percentage. The main limitation is that depth images were generated by means of photogrammetry methods, which limits the efficiency of data acquisition. To overcome this limitation, future works should consider the use of commercial RGB-D sensors. The code and the dataset used to evaluate the method have been made publicly available at https://github.com/GRAP-UdL-AT/Amodal_Fruit_Sizing.

Photogrammetry-Based 3D Textured Point Cloud Models Building and Rock Structure Estimation

Trace lines on the outcrop of a rock mass are usually the primary data source for the estimation of rock structure. It is important to obtain the data of trace lines precisely. Photogrammetry is well suited to finish this task. However, this is mainly conducted by commercial software, and not every researcher has easy access to the method of digital photogrammetry. This study aims to provide researchers with a low-cost method of building a photogrammetry-based textured 3D point cloud model (FMBPM) and display the applicability of the method to estimating the rock structure of rock masses. In the FMBPM, a digital single-lens reflex camera with a prime lens and a total station are the necessary hardware employed to capture images and measure the coordinates of feature points. A coordinate transformation means of converting model coordinates to physical coordinates was introduced. A program for calculating a joint orientation based on the coordinates of inflection points on the trace line of the joint was developed. A section of a rock slope was selected as a case to show the procedures and the practicability of the FMBPM. The textured 3D point cloud model of the rock slope was successfully built, and the rock structure of the rock slope was analyzed using the joint disk model generated based on the trace lines extracted from the point cloud model. The results show that: (1) the precision of the point coordinates of the textured 3D point cloud model could achieve 3.96 mm, taking the data of the total station as the reference; (2) the rock structure of the slope is good, according to the value of the rock quality designation; (3) the new method is applicable in engineering practices.

A new method for constructing roads map in forest area using UAV images

High definition map is a map used for automatic driving. Its absolute precision is sub meter level, that is, the error between the position of an element on the map and the position of the element in the real world is less than 100 cm. In addition, compared with ordinary maps, high definition maps contain more geographic information, such as road width, slope, curvature, etc. At present, high definition roads map construction is largely for the main traffic road. However, there are few studies on the construction of high definition forest roads map for forestry production and management. Thus, it is imperative and helpful to explore an efficient and low-cost method for constructing high definition forest roads map that can provide accurate basic map services for forestry management activities. In this study, firstly, the DJI Phantom 4 RTK UAV was used for aerial photography to obtain the forest oblique images. Then, combined with close range photogrammetry, the high-resolution images under the forest are acquired and generated into dense point cloud images. Next, the two images are fused using iterative closest point (ICP) algorithm combined with manual registration; Finally, the fine-grained 3D scene model is generated by using the Context Capture 3D modeling software, based on which a high definition forest roads map was constructed using human-computer interaction model. Taking Menggongshan Forest Farm as an example, the construction of the fine 3D scene model was carried out to solve the problem of loopholes and ambiguities of the road model under forest, based on which the high definition forest roads map was constructed. To evaluate the accuracy of the forest roads map, the accuracy check was conducted. The results showed that the point position on the forest roads map, compared to the actual point, had a medium, minimum and maximum error of 0.076 m, 0.020 m and 0.170 m in plane, respectively, a medium, minimum and maximum error of 0.122 m, 0.005 m and -0.214 m in elevation, respectively. The accuracy of the high definition forest roads map meets the need of forestry production and management activities. It is feasible to adopt the method of UAV oblique photogrammetry combined with close-range photogrammetry, fine 3D scene model construction and human-computer interactive for constructing high definition forest road map. And this method can provide a low-cost and high-efficiency way for constructing high definition forest roads map, and also can better provide basic map data for forest management activities.

Computer and Physical Modeling for the Estimation of the Possibility of Application of Convolutional Neural Networks in Close-Range Photogrammetry

Close-range photogrammetry is widely used to measure the surface shape of various objects and its deformations. The classic approach for this is to use a stereo pair of images, which are captured from different angles using two digital video cameras. The surface shape is measured by triangulating a set of corresponding two-dimensional points from these images using a predetermined location of cameras relative to each other. Various algorithms are used to find these points. Several photogrammetry methods use cross-correlation for this purpose. This paper discusses the possibility of replacing the correlation algorithm with neural networks to determine displacements of small areas in the images. They allow increasing the calculation speed and the spatial resolution of the measurement results. To verify the possibility of using convolutional networks for photogrammetry tasks, computer and physical modeling were carried out. For the first test, a set of synthetically generated images representing images of the Particle Image Velocimetry method was used. The displacements of particles in the images are known, it allows to estimate the accuracy of processing of such images. For the second test, a series of experimental images with surfaces with different deformation was obtained. Computational experiments were performed to process synthetic and experimental images using selected neural networks and a classical cross-correlation algorithm. The limitations on the use of the compared algorithms were determined and their error in reconstructing the three-dimensional shape of the surface was evaluated. Computer and physical modeling have shown the operability and efficiency of neural networks for processing photogrammetry images.

Use of scanning devices for object 3D reconstruction by photogrammetry and visualization in virtual reality

This article aims to compare two different scanning devices (360 camera and digital single lens reflex (DSLR) camera) and their properties in the three-dimensional (3D) reconstruction of the object by the photogrammetry method. The article first describes the various stages of the process of 3D modeling and reconstruction of the object. A point cloud generated to the 3D model of the object, including textures, is created in the following steps. The scanning devices are compared under the same conditions and time from capturing the image of a real object to its 3D reconstruction. The attributes of the scanned image of the recon-structed 3D model, which is a mandarin tree in a citrus greenhouse in a daylight environment, are also compared. Both created models are also compared visually. That visual comparison reveals the possibilities in the application of both scanning devices can be found in the process of 3D reconstruction of the object by photogrammetry. The results of this research can be applied in the field of 3D modeling of a real object using 3D models in virtual reality, 3D printing, 3D visualization, image analysis, and 3D online presentation.

Correlation of mobile phone usage on grip strength, disabilities and posture in young adults

Background: The musculoskeletal issues are now common in excessive use of mobile phone for communication, gamming and socialization on internet. The excessive use of mobile phone may decrease the muscle strength and lead to poor posture ultimately functional impairment related to upper extremity. Objective: to determine correlation among duration of mobile phone usage, neck posture, disabilities and hand grip strength. Methods: A correlational cross sectional study was done at Riphah International University Lahore from March 2020 to February 2021. The target population was male and female young students of 18 to 24 years, used mobile phone more than 6 hours in a day. A total of n=400 subjectsarticipated in the study in which n=235 were females and n=165 were males. The information was gathered using the DASH Questionnaire to identify upper limb problems, the photogrammetry method to determine the cervical angle, and a dynamometer to determine the strength of each hand's grasp. The pearson product-moment correlation coefficient was done by using SPSS version 21. Result: The mean age of the study participant was 20.99±2.34 years. A total of n=165(41.25%) were male and remaining n=235 were female participated in the study. Increase use of mobile had negative significant small correlation with degree of cervical angle (p=0.04), right hand grip strength (p=0.01) and positive significant small correlation with DASH score (0.01). While no significant correlation between daily use of mobile phone and left hand grip strength Conclusion: The study concluded that as the duration of mobile phone usage increased, the forward head posture and disabilities of the upper limb also increased. But the grip strength of right hand decreased as the mobile phone duration is increased. Key words: Correlation, disabilities, female, grip strength, mobile phone, male, posture.

NORMAL AND CONVERGENT METHODS OF SURVEY FOR INVENTORY AND CERTIFICATION OF CULTURAL STRUCTURES

The article aims to study the use of normal and convergent stereo-photographic techniques to determine physical condition of a building, to compare errors obtained using a digital non-specialized camera, and use these methods in the inventory and certification of real estate. Monitoring architectural monuments is currently one of the most urgent problems. The development of large cities in which architectural monuments are under threat of destruction requires modern and effective technology for monitoring which is possible using low-cost photogrammetry methods: digital images and cheap software. The development of digital cameras into terrestrial photogrammetry resulted in fundamentally new methods and photogrammetric technologies. In case of monitoring objects of small sizes, such as architectural monuments, the cost of shooting equipment is one of the most significant factors, which reduces the cost of work, therefore, in the vast majority of cases, only digital non-metric cameras are used for shooting. The most significant problem is the calibration of digital non-metric cameras. Currently, a huge number of options for calibrating digital cameras have been developed. These options differ in calibration method, type of test object, type of mathematical model for accounting for distortion (algebraic, physical or hybrid model) The present study how that accuracy of the convergent method is almost 2 times higher than that of the normal photogrammetric survey method and provides a large survey overlap area. Comparing all the indicators and characteristics of these methods, we concluded the feasibility, high profitability, and low complexity of the convergent method of stereo photography to perform inventory and certification of real estate. We found that when surveying building using convergent method it is necessary to use 2 times fewer stations than when surveying by normal method. Thus, the convergent method is 2 times faster and more efficiently.

Anatomical Basis for the Lower Eyelid Rejuvenation.

The tear trough, hollow concavity of the lower eyelid, is one of the recognizable signs of facial aging. Anatomical description is essential in improving tear through deformity for facial rejuvenation. Fifty cadaver were microdissected. Fat pad types, fat herniation and the fibrous support system of lower lid were investigated. The areas of the fat compartments were compared using photogrammetry method and ImageJ software. Lower lids develop palpebral bags as a result of herniation of orbital fat against a weak orbital septum in all cases (%100). The attachment of the arcus marginalis at the orbital edge is a large contributor to the middle-aged appearance of the midface in all cases (100%). The most common type is Type 1 (36%). In this type, three distinct fat pads were diverged by arcuate expansion at lateral, fascia of the inferior oblique muscle at medial, as central, medial and lateral. Type 2 specimens (20%) were observed with two fat pads. Double convexity contour is in Type 3 cases (%44). It is determined that the medial fat pads are located in larger areas. Also, herniation is particularly evident in the medial and mediocentral fat pads. Analysis of the lower lid morphology enables surgeons to apply safe and effective procedures. The inferior oblique muscle and arcuate expansion structures should be supported and not be damaged during surgical interventions. Surgeons should focus mainly on the anatomical data obtained, and in this sense, surgeons apply them during aesthetic and reconstructive procedures of the lower eyelids. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Application 3D Forensic Science in a Criminal Investigation

This manuscript discusses the modern approach and application of 3D digital imaging in forensic science. It presents the basic principles and approaches of 3D modeling methods. Selected methods of image capture and its subsequent processing into a 3D model are applied to a specific object. This object is captured by a mobile phone camera, a LiDar sensor, and a 3D scanner for further image processing for different desired image outputs. The text describes the photogrammetry method, the workflow with the LiDar sensor, and the 3D model of the object intended for 3D printing. The paper discusses the potential of the selected methods and their application in forensic sciences.