Optical Ortho-Rectification for Image-Based Stream Surface Flow Observations Using a Ground Camera

Image-based stream flow observation consists of three components: (i) image acquisition, (ii) ortho-rectification, and (iii) an image-based velocity estimation. Ortho-rectification is a type of coordinate transformation. When ortho-rectifying a raster image, pixel interpolation is needed and causes the degradation of image resolution, especially in areas located far from the camera and in the direction parallel to the viewing angle. When measuring the water surface flow of rivers with a wide channel width, reduced and distorted image resolution limits the applicability of image-based flow observations using terrestrial image acquisition. Here, we propose a new approach for ortho-rectification using an optical system. We employed an optical system embedded in an ultra-short throw projector. In the proposed approach, ortho-rectified images were obtained during the image acquisition phase, and the image resolution of recorded images was almost uniform in terms of physical coordinates. By conducting field measurements, characteristics of the proposed approach were validated and compared to a conventional approach.

Research on Estimation Method of Geometric Features of Structured Negative Obstacle Based on Single-Frame 3D Laser Point Cloud

A single VLP-16 LiDAR estimation method based on a single-frame 3D laser point cloud is proposed to address the problem of estimating negative obstacles’ geometrical features in structured environments. Firstly, a distance measurement method is developed to determine the estimation range of the negative obstacle, which can be used to verify the accuracy of distance estimation. Secondly, the 3D point cloud of a negative obstacle is transformed into a 2D elevation raster image, making the detection and estimation of negative obstacles more intuitive and accurate. Thirdly, we compare the effects of a StatisticalOutlierRemoval filter, RadiusOutlier removal, and Conditional removal on 3D point clouds, and the effects of a Gauss filter, Median filter, and Aver filter on 2D image denoising, and design a flowchart for point cloud and image noise reduction and denoising. Finally, a geometrical feature estimation method is proposed based on the elevation raster image. The negative obstacle image in the raster is used as an auxiliary line, and the number of pixels is derived from the OpenCV-based Progressive Probabilistic Hough Transform to estimate the geometrical features of the negative obstacle based on the raster size. The experimental results show that the algorithm has high accuracy in estimating the geometric characteristics of negative obstacles on structured roads and has a practical application value for LiDAR environment perception research.

Printed text documents watermarking based on vertical word shift and word fragments brightness changing

This paper describes the results of the development of methods for marking text documents represented as a raster image. An important feature of the algorithms is the possibility wipe current document mark and embed another one. The study refers to structural marking algorithms based on vertical word shifts and brightness changes of certain areas of the words. Segmentation tools are used to obtain document layout, BCH codes for error correction, a likelihood maximization method for label extraction, and a neural network for perturbed words recovery. Testing has proved the practical applicability of the algorithms with printing and scanning.

The mapping of raster images on plane isometric grid

Drawing images on curvilinear shapes with the least distortion takes place in many design tasks. In most ways, build a grid, each elementary cell of which is painted a given color. In this problem it is necessary to solve two main problems: the first - to carry out the formation of a given curvilinear grid with elementary cells in the form of squares, which are called isometric (or isothermal); the second is to paint each cell of the curved area with the corresponding pixel color of the original raster The aim of the study is to reveal the way of displaying raster images on flat curvilinear areas represented by isometric grids, and with the help of a computer model in the Maple symbolic algebra to analyze the influence of isometric grid parameters on the position and size of displayed raster images. The mapping of images onto curvilinear forms with minimal distortion takes place in many design tasks. A method of conformal mapping of arbitrary raster images onto plane curvilinear region is proposed, which are represented by isometric (also called isothermal) grids. The essence of the proposed method is as follows. Any raster image, for example, digital photography in jpg format, is characterized by the dimensions N×M - the number of pixels in width and height. In addition, each pixel has a color and brightness, which are arranged in rows and columns. To apply a raster image to a curvilinear region, it is also necessary to divide the curvilinear domain into N×M, the number of elementary squares, each of which is assigned the corresponding color from the raster. The influence and arguments of the various isometric grids constructed on the sizes and positions of an arbitrary raster image are investigated in the article. It is shown how the isometric grid, depending on and localizes the raster image - it can be located both within the limits of the isometric grid coordinate lines and beyond it, can also be oriented in different directions with respect to the and coordinate lines. It is shown the possibility of scaling a raster image that can be performed relative to the relative dimensions of an isometric grid. Since there is a correspondence between the pixel matrix of the original raster image and the - cells of the isometric grid, the rotation of the image will affect its position in the isometric grid. For example, rotating the original bitmap image at an angle 90 degrees will change its location on a plane isometric grids – from along the coordinate lines to along the coordinate lines. Note that, the curvilinear cells of the constructed isometric grids differ somewhat from the shape of the squares because the values and of the corresponding arguments and of their coordinate lines were taken somewhat too large. Otherwise, cells would degenerate into points and the corresponding grid image would not be so clear.

Geometric Modeling of Stress Visualization Based on the Functional-Voxel Method

The visualization of the parameters of the stress state of a solid remains one of the parameters influencing the adoption of engineering decisions. For example, methods for determining finite elements (FEM), which make it possible to determine and visualize stress in the selected regions of the model. Applying element methods to analytically constructed models to localize the search for stress to its values at a point, however, will not lead to successful results. The paper discusses the principles of visualization of local stresses based on the functional-voxel method. The concept of a volume vector as a unit of volume distribution of a force vector in a solid isotropic medium is introduced. Geometrical foundations are proposed for computer representation of the stress unit in an isomorphic body based on a raster image. Geometric models of the stress tensor are constructed for the main site, the inclined platform. The principles of applying the functional-voxel model in the tasks of constructing complex objects are proposed. The application of the functional voxel method for discrete modeling of the deformation of a geometric object is illustrated by the example of a function that describes a rectangular plate.

Lateral diffusion of CD14 and TLR2 in macrophage plasma membrane assessed by raster image correlation spectroscopy and single particle tracking

The diffusion of membrane receptors is central to many biological processes, such as signal transduction, molecule translocation, and ion transport, among others; consequently, several advanced fluorescence microscopy techniques have been developed to measure membrane receptor mobility within live cells. The membrane-anchored receptor cluster of differentiation 14 (CD14) and the transmembrane toll-like receptor 2 (TLR2) are important receptors in the plasma membrane of macrophages that activate the intracellular signaling cascade in response to pathogenic stimuli. The aim of the present work was to compare the diffusion coefficients of CD14 and TLR2 on the apical and basal membranes of macrophages using two fluorescence-based methods: raster image correlation spectroscopy (RICS) and single particle tracking (SPT). In the basal membrane, the diffusion coefficients obtained from SPT and RICS were found to be comparable and revealed significantly faster diffusion of CD14 compared with TLR2. In addition, RICS showed that the diffusion of both receptors was significantly faster in the apical membrane than in the basal membrane, suggesting diffusion hindrance by the adhesion of the cells to the substrate. This finding highlights the importance of selecting the appropriate membrane (i.e., basal or apical) and corresponding method when measuring receptor diffusion in live cells. Accurately knowing the diffusion coefficient of two macrophage receptors involved in the response to pathogen insults will facilitate the study of changes that occur in signaling in these cells as a result of aging and disease.

Creation of geo-information basis for land cadaster by mapping method

The technology of the mapping method for creation of a geo-information basis of cadastral registration using Microsoft Office and AutoCad has been developed by the authors. The technology includes the introduction of the original land and linking the raster tablets to the contour of the original land in AutoCad. The first question is solved by using the Polygon software according to Excel data and copying from the original drawing from AutoCad. The methods are implemented by a wide range of Excel features, which are important in the cadastral engineer's practice. The second issue – linking the raster tablets to the contour of the original land - is implemented by the introduction of the original land on the screen, the insertion of the raster image, the graphic binding of the tablet's raster at identical points, and setting the raster trying to save maximum information on the plan.

Sector Rasterization Method for Images on a Video Device With Mechanical Scanning

The goal of this work was to create a method for sectoral rasterization for images on video devices with mechanical scanning that can be used for advertising purposes. Preparing an image for display on a machine with a mechanical sector scan requires the creation of software for transferring a classic rectangular raster to a sector raster. When implementing software for an embedded computing system of mechanical image scanning for advertising purposes, the task was to reproduce a raster image using concentrically located circles, which are divided into sectors. The ambiguity of the transition from a square to a sectorial raster lies in the variable area of the sectors as they move away from the center of the image. According to this fact, there are several sectors for each of the pixels near the central zone of the image, and several pixels for one sector to the periphery of the image. There is not possible to increase the resolution of a sector image due to hardware limitations, so a new method of sector rasterization for an image on a mechanically scanned video device was developed. The developed method combines algorithms that make it possible to transform a raster image into a sectorial raster using linear interpolation depending on the distance of the sector from the center of the image. Attention was also paid to assessing the time of the next complete revolution when starting the mechanical scanning system, which made it possible to reduce the time for obtaining a stable image from the moment the device was turned on. So, as the result of the research, the method of sectorial image rasterization was developed, as well as the algorithms that allow converting a raster image into a sectorial image were developed. Вased on the developed algorithms, the software product for an embedded image reproduction system and the software product for real-time video transmission over Wi-Fi communication with the conversion of a rectangular raster into a sector raster were created. By combining algorithms for converting a square raster to a sector one, the quality of image reproduction on a mechanically scanned video device was improved.

Application of GIS in Electricity Distribution: A Case Study of part of Ashamu Layout Kosobo, Oyo East Local Government Area, Oyo State Nigeria

Due to the natural limitations faced by the old system of keeping, planning and managing the distribution of electricity, a computerized system is developed for Power Holding Company of Nigeria (PHCN), on Ashamu Layout of Kosobo Area, Oyo State, Nigeria. Data was acquired using south total station (NTS) and the data was downloaded using NTS.comp and project boundary was plotted with AutoCAD civil 3D, 1m Ikonos resolution satellite imagery was downloaded and geo-referenced with Arcgis10.1. Spatial features such as roads and buildings were vectorized. Electricity distribution and management was designed and created using relational database management system (rdbms) approach. The raster image was added as layer to ArcGIS 10.1 environments for geo-referencing and vectorization. The roads, buildings, electric poles were vectorized and a south total station was used to acquire co-ordinates of the electric poles and transformers to their position on the imagery, creating spatial database for the study area. The developed system was tested by carrying out spatial analysis and spatial search using ArcGIS 10.1. The results obtained were displayed in graphics and tables. It was established from the result that Geographic Information System (GIS) has the capacity as an effective tool for management of electricity distribution system.