161 results about "Point density" patented technology

The performance of detecting the features of an object is to be improved. In one step, among pixels within a ROI, pixels whose feature amount is greater than a predetermined threshold value are extracted as a feature point candidate. In another step, a feature point density parameter is set based on a distance to an object within the ROI. In another steps, the feature points are extracted from the feature point candidates in the descending order of the feature amount, while the feature point candidates, whose distance from the extracted feature points is equal to or smaller than the feature point density parameter, are not extracted as the feature point. In another step, a feature point list representing the feature points extracted from the ROT is output. The present invention can be applied to an in-vehicle obstacle detecting device.

The invention relates to a method suitable for multi-view-angle automatic global registration of ground laser point cloud data. The method involves two key modules: a module for extracting semantic feature points and a module for feature matching. The method comprises: step 1, extracting the semantic feature points: obtaining the semantic feature points in a series of modes of data slicing, distance clustering, geometric element fitting and the like; step 2, matching the semantic feature points: matching the semantic feature points by constructing a triangular geometric constraint condition and a semantic constraint condition, and removing error matching in a geometric consistency clustering mode; and finally, constructing a weighted undirected graph by taking a reciprocal of a feature point number as a weight, and finally obtaining global registration parameters of all stations by taking a minimum spanning tree of the weighted undirected graph as a registration path, thereby realizing global optimal registration. According to the invention, the method suitable for multi-view-angle automatic global registration of the ground laser point cloud data is constructed; the method can effectively resist influences of noise, point density and coverage; and the method improves the laser scanning operation efficiency, thereby having very high practical values.

The invention relates to an automatic laser scanning data physical plane extraction method with multi-scale characteristics fused. Existing problems solved by the method of the invention mainly comprise: 1, an optimal neighborhood adaptive determination method based on information entropy is developed, and influences on three-dimensional point local geometric characteristic calculation by factors such as point density changes, noise and data missing are overcome; 2, point-based characteristics (such as dimension characteristics and a normal vector) and region-based characteristics (such as roughness, compactness, a scale and a length-width ratio) are used comprehensively to carry out extraction of a physical plane region, and thus accuracy of physical plane extraction is improved; and 3, the existing plane segmentation method application range is expanded. The method of the invention is applicable to physical plane extraction for laser scanning data with an airborne type, a vehicle-mounted type, a fixed station type and the like. The overall technical flow chart is as follows.

The invention relates to a method and a system for discovering a user residence position based on mobile phone signaling. The method comprises the following steps: the obtained mobile phone signalingdata of the user is taken as the original trajectory data, and the original trajectory data is sequentially processed by data cleaning, data slicing, preliminary clustering, data verification and corecluster calculation, and finally the user staying position is obtained. Adopting a series of algorithms such as track slice aggregation, hierarchical clustering algorithm, kernel density clustering algorithm and machine learning algorithm, etc., considering mobile phone track point density, signaling time interval, track point moving direction and moving distance, etc., we can judge user 's staying position, staying time, entering and leaving staying point time. The algorithm can effectively eliminate the interference of base station drift on user location judgment, improve the identificationaccuracy of user dwell point position and dwell time, and objectively restore the user dwell position.

The invention is suitable for the field of design of mesh points of a light guide plate, and provides a method and a device for optimizing the mesh points of the light guide plate. The method comprises: determining the position of each mesh point according to the size of the light guide plate and the horizontal spacing and vertical spacing of centers of adjacent mesh points, and determining firstmesh point density distribution according to the position relationship of an LED (light-emitting diode) lamp and the light guide plate; obtaining the center coordinates, shape and area of a supplementary point area to determine the supplementary point area, changing the mesh point density of the supplementary point area according to the obtained supplementary point strength, and thus obtaining second mesh point density distribution, wherein the supplementary point strength is used for determining the ratio of changes in the sizes of mesh points in the supplementary point area; and setting different mesh point marks for the mesh points with different sizes according to the second mesh point density distribution, and displaying the mesh point marks. The distribution of the mesh points of the light guide plate can be simulated. Moreover, different mesh point marks can be set for the mesh points according to the sizes of the simulated mesh points, the sizes of the mesh points can be directly distinguished, the development cost can be reduced, and the development cycle can be shortened.

The invention discloses a rural resident point information extraction method based on a high-resolution remote-sensing image. The rural resident point information extraction method comprises the following steps: firstly, carrying out Canny edge detection on the high-resolution remote-sensing image, and obtaining a vector edge line through chain code tracking; then, carrying out Douglas-Peucker abbreviation on a vector edge to extract straight-line segments, and rejecting shorter straight-line segments and keeping longer straight-line segments according to length constraints; secondly, according to adjacency relation between the straight-line segments and included angle constraints, extracting straight angle points, calculating the density characteristics of the straight angle points within a certain space region range, and generating a straight angle point density characteristic image, wherein the characteristic image and the input high-resolution remote-sensing image have same spatial range and spatial resolution; and finally, carrying out binarization processing on the density characteristic image by utilizing Otsu, extracting rural resident point vector pattern spots through connected component analysis so as to extract rural resident point information. Precision and effects are improved, and robustness and universality are better.

A brand new lattice two-dimensional code solves the problems of limited coding capacity and poor safety anti-counterfeiting property of an existing two-dimensional code. The brand new lattice two-dimensional code is formed by splicing a plurality of different code graphs corresponding to the same code; each code graph is formed by distributing adjustable solid round points or square points with the same size on rectangular arrays of which the spacing is adjustable and which are arranged at an equal interval; each code graph consists of a location zone 1, key zones 2.1 and 2.2, and a data zone 3 containing a single-place CRC check code zone 3.1; the positions of black points in the data zone respectively represent all places of a code expressed by a decimal number and numbers in the range of 0 to 9 in the check code; an original data zone array image is scrambled by scramble transformation; a number of corresponding scramble times is a password; and a plurality of previous scramble arrays with the highest scramble degrees are used as final data zone arrays of the code graphs. The two-dimensional code solves the contradiction between high coding capacity and high point density, has high capacity and good concealment, is easy in expansion and strong in safety anti-counterfeiting property, and is especially suitable in the field of logistic monitoring, product source tracing, audio books and the like.

In a cost-efficient method and arrangement for 3D digitization of bodies and body parts, which produces dense and exact spatial coordinates despite imprecise optics and mechanics, the body to be digitized is placed on a photogrammetrically marked surface, a photogrammetrically marked band is fitted to the body or body part to be digitized, and a triangulation arrangement comprised of a camera and a light pattern projector is moved on a path around the body. By a photogrammetric evaluation of the photogrammetric marks of the surface and the band situated in the image field of the camera, and of the light traces of the light projector on the marked surface and the marked band, all unknown internal and external parameters of the triangulation arrangement are determined, and the absolute spatial coordinates of the body or body part are established from the light traces on the non-marked body with high point density and high precision without any separate calibration methods.

The invention relates to a laser welding device of a solar flat plate collector. The laser welding device is characterized by comprising a frame, a solid pulse laser system and a control system. An XY-axis servo driving mechanism is arranged on the frame, a Z-axis lifting mechanism and a laser welding head are arranged on the XY-axis servo driving mechanism through a dragging plate, and a rotating table is arranged below the laser welding head. The laser welding device adopts a high-power solid pulse laser system, a high-speed precise linear module is used as an XY-axis transmission guiding component, the device operates stably, device welding speed is increased, welding point density is increased, welding quality is improved, and heat transmission effect of the solar flat plate collector is improved. The Z-axis lifting mechanism adopts a series connection structure of three cylinders, the laser welding head is lifted and lowered stably in subsection mode, damage such as copper pipe dent is reduced, product quality is improved, and production cost is reduced. A double-station rotating table structure is adopted, operators do not need to walk back and forth, labor intensity is lowered, and production efficiency is increased.

PROBLEM: Efficiently generating digital terrain model (DTM) having high elevation surface accuracy and high point density, and suitable for controlling pavement milling machines during road repairs. SOLUTION: Combination of motorized levelling and Stop-Go mobile laser scanning system, including train of three vehicles, which are at standstill during measurements, and which move in unison in between measurements. Middle vehicle carries laser scanner, elevation sight, and GNSS receiver. Front and rear vehicle each carry levelling rod; front vehicle also carries GNSS receiver. During measurement cycle, laser scanner generates point cloud, while GNSS positions of middle and front vehicles and elevations at the resp. positions of front and rear vehicles are determined. After measurement cycle, vehicle train moves until rear vehicle halts at previous GNSS position of front vehicle, etc. When all measurement cycles are completed, collected data is integrated and transformed into a DTM.

The invention provides a vanishing point detecting device and a detecting method, and the vanishing point detecting device comprises a line segment detecting unit used for obtaining a horizontal line segment or a vertical line segment of an input image, an intersection point set obtaining device used for obtaining the intersection point set of the horizontal line segment or an intersection point set of the vertical line segment, a candidate vanishing point detecting unit used for determining a candidate vanishing point, and a vanishing point determining unit used for determining a final vanishing point according to the candidate vanishing point determined by the candidate vanishing point detecting unit; wherein the candidate vanishing point detecting unit is one or more of the following: a candidate vanishing point detecting unit based on fanning beam projection and density estimation, which carries out fanning beam projection to the input image and takes the intersection point with the highest point density in a high-density fanning beam area as the candidate vanishing point; a candidate vanishing point detecting unit based on fanning beam projection and clustering, which carries out the fanning beam projection, obtains a plurality of clustering of the intersection points in the high-density fanning beam area and takes the center of each clustering as the candidate vanishing point.

The invention discloses a Voronoi (V) and inverse distance weighting combined density map drawing method which comprises the steps that discrete point data is read; a V map is constructed by discrete points; a whole V map area is rasterized; a density value of pixels is computed according to a subordination relationship between the pixels and a V polygon and distances between a pixel center point in the V polygon and the discrete points; and all generated grids are rendered finally after subjected to neighborhood mean value smoothing processing, re-classified, and endowed with different gray-scale values in order to make results more reasonable. The V map constructed based on the discrete points is divided into generation influence ranges of the discrete points by a space constrained based on the shortest distance, and local density computation is performed within the ranges, so that the comparability and the reliability of computation results among the various influence ranges are guaranteed; and the method takes account of differences of the point density of the different pixels within the influence ranges, and a density value distribution method based on the distances is adopted in the V polygon where each point is located, so that the results are more reasonable and accurate.

The invention relates to a rapid image recognizing method of a power tower pole outline. The method comprises the following steps: (1) converting a shot color image into a gray level image through brightness calculation, and carrying out smooth denoising on the image; (2) based on an improved Harris angle point detecting method, realizing the detection to power tower pole pixel in an outline image of a known area shape; (3) firstly gridding the image, and subsequently calibrating the power tower pole pixel by adopting a gridding angle point density clustering algorithm through the clustering to the angle point density; and (4) calibrating and outputting the power tower pole pixel. By detecting a pole tower area in the image, a small range area for detecting various members can be provided; detailed capital construction data of each pole tower are backed up and can be checked in power departments; specific positions and numbers of various members in the image can be extracted accurately based on the information, and moreover the intelligent diagnosis to normal faults of various members can be further realized.

The invention discloses an image character positioning method and device. The method includes the steps of obtaining a target image sequence with multiple frames of target images, conducting horizontal weighted projection and vertical weighted projection on each frame of target image, combining weighted projection results to generate character areas, determining character spare areas in the character areas according to the character height values, the edge point density and the area main direction, adding the corresponding character spare areas in the target images together, further obtaining a target connected domain, and correcting the target corrected domain through an area reprojection method to obtain target character areas.

Methods and apparatuses are disclosed for generating three dimensional (3D) vertical seismic profiles (VSPs) in a more time efficient manner. The methods and apparatuses enable faster and more efficient VSP surveys than previous techniques. Real-time updating of the velocity model and real-time reflection point density calculations are carried out, which are used to determine the location of the next seismic source firing. In the event the data of a particular bin has an insufficient fold, common image points (CIPs) or reflection point density, additional source firings may be carried out prior to moving the source. Further, in the event the data of a particular bin is excessive in terms of the fold, CIPs or reflection point density before the planned source firings for the bin are completed, remaining source firings for that bin may be skipped to save time and improve the efficiency of the data collection.

The invention relates to an LED display screen composed of pixel points of different densities and the LED features diversified structures and wide application range and a display method thereof. The technical proposal is that the LCD display screen is composed of a plurality of pixel panels and is characterized in that the pixel panels are ones with a plurality of pixel density levels. display method comprises the following steps: (1) recording positions of each row and each array of the pixel points; (2) reading displayed image data information with the calculation basis that all pixel panels of the display screen have the highest level of pixel point density; (3) reading the image data information of corresponding pixel point positions in step (2) according to the pixel point positions of the rows and arrays of pixel points in step (1); (4) transmitting the image data information to the display screen to be displayed.

The invention discloses a screen content coding predicting mode quick selection method based on edge point density, wherein the screen content coding predicting mode quick selection method mainly settles a problem of high computing complexity in prior art. The technical solution of the screen content coding predicting mode quick selection method is characterized in that the code sequence of a screen content coding (SCC) predicting mode is adjusted to IBC-2N-2N predicting mode, IBC-2N*N predicting mode, IBC-N*2N predicting mode, IBC-N*N predicting mode, in-frame Intra predicting mode and PLT predicting mode. Every time coding of one predicting mode is finished, a coding block flag (CBF) and a block vector difference (BVD) are detected for determining whether the coding block flag and the block vector difference are 0 and (0,0) respectively, and if yes, coding of subsequent predicting modes is skipped, and otherwise, coding of the subsequent predicting modes is successively performed until an optimal predicting mode is selected. The screen content coding predicting mode quick selection method can quickly differentiate cartoon-type video sequence and furthermore reduces coding time for cartoon-type and non-cartoon type video sequences. The screen content coding predicting mode quick selection method can be used for video processing.

Systems, methods, and apparatuses are disclosed for simplifying a point cloud. A point cloud is received where the point cloud has a plurality of points, a global spatial structure, and a local point density. The processor calculates a set of pairwise distances for the plurality of points to at least one other point in the plurality of points. A first distance matrix is generated using the set of pairwise distances. The processor calculates a second pairwise distance set where the plurality of points have a weight and generates a second distance matrix based off the second pairwise distance set. A portion of the points in the second pairwise distance set are removed based on the weight. The processor performs a comparison of the two matrices using the comparison and the global spatial structure and the local point density, and generates a second point cloud based on the second distance matrix.

The invention discloses a state integral gradient-repair algorithm based fast trajectory optimization method of a hypersonic aerocraft. The method comprises the steps as follows: 1, performing dimensionless processing on a dynamical model of the hypersonic aerocraft, performing reasonable transformation on process constraint conditions and terminal constraint conditions in trajectory optimization,selecting a sampling point density based on a precision demand of the trajectory optimization and determining a trajectory optimization model; 2, judging a satisfaction condition of the flight trackof the hypersonic aerocraft for a constraint equation and an optimal equation under an initial condition or after gradient approximation operation; and 3, smoothening the obtained optimization result,removing jump points in a controlled quantity result and smoothening by applying an interpolation method. The state integral gradient-repair algorithm based fast trajectory optimization method of thehypersonic aerocraft solves the fast trajectory optimization problem of the hypersonic aerocraft in a complex flight environment.

The invention discloses an intelligent transportation business management method. The intelligent transportation business management method is characterized by including displaying basic monitoring information and road information graphically; clicking and taking real-time images from monitoring points; performing layering management on map data according to type, and arranging related data in the same layer to enable a user to conveniently set layers to be displayed, concealed or marked according to needs; performing basic information inquiry; supporting an equipment attribute direct positioning map, inquiring related targets in all layers or designated-type layers through input of the user, and positioning the targets on the map by clicking searched records to enable the objects to be displayed or marked in a centered mode; performing graphic output; supporting statistics and analysis of various information in a graph and map combination mode, and providing multiple thematic maps such as areal maps, histograms, pie charts, class notation diagrams and point density diagrams.

The invention discloses a method of extracting substation information in a power distribution system based on hyperspectral remote sensing images. The method comprises the steps of firstly classifying hyperspectral remote sensing images using a decision tree algorithm, and then conducting edge detection of the classified hyperspectral remote sensing images to obtain vector edge lines; secondly, extracting straight line segments from the vector edges, removing the shorter straight line segments and retaining the longer ones; thirdly, extracting right angle points according to the adjacency relation among the straight line segments and included angle constraints, conducting statistics on the density features of the right angle points in a certain spatial region, and generating a right angle point density feature image; and fourthly, binarizing the density feature image using an otsu method, extracting substation vector pattern spots through connect component analysis, and thus achieving extraction of the substation information. The invention solves the classification problem of hyperspectral remote sensing images, satisfies the requirements for the extraction of the substation information in the hyperspectral remote sensing images, and improves the robustness and universality in extraction of the substation information.

The embodiments of the invention disclose a power tower automatic positioning method and apparatus based on an unmanned aerial vehicle laser point cloud, for solving the problems of limited application scenes and accuracy instability existing in a conventional power tower positioning method in an airborne LiDAR point cloud. The method provided by one embodiment comprises the following steps: performing grid processing on a point cloud area obtained by an unmanned aerial vehicle, respectively counting an elevation highest point in each grid scope to obtain a highest elevation graph and counting an elevation lowest point to obtain a lowest elevation graph, obtaining a density feature graph by counting point density, and obtaining a high-difference distribution feature graph and a gradient distribution feature graph through calculation; according to the high-difference distribution feature graph and the gradient distribution feature graph, extracting power line seed points, forming a seed area, and performing morphological closing operation on the seed area to obtain a mask area; and by use of a local high density point location method of iteration, according to the density feature graph, calculating the mask area, and outputting a power tower positioning area graph.

The invention discloses a preparation method of a polymer based three-dimensional (3D) biochip and belongs to the technical field of biochip preparation. The invention discloses a method for preparing the 3D biochip with controllable ingredient content by means of surface activity grafting polymerization technology. The method comprises the following steps of: taking a polymer membrane as a substrate, coupling a semipinacol dormant group on the membrane surface by means of UV (Ultraviolet) radiation, grafting a monomer with biological contamination resistance on the membrane surface by means of visible light / ultraviolet to endow the surface with biological contamination resistance, at last again initiating a grafting monomer mixed solution using a photographic mask under the visible light / ultraviolet to finally obtain the surface functional micro-gel array with controllable thickness, wherein the monomer mixed solution comprises a functional group capable of fixing a biological molecule. The novel 3D biochip, which is low in cost, environment-friendly, simple and convenient in process, high in array point density, high in biomolecule density and strong in fluorescence signal, can be obtained by combining the functional group on the microarray with biologic components of protein, gene and the like, and therefore the preparation method has excellent application prospect.

The invention relates to a method for operating a magnetic resonance imaging system, wherein, the primary magnetic resonance data are collected; and a space K is established in a computerized storing medium, wherein, the space K is divided into an adjacent center area and an adjacent area surrounding the center area. In the computerized process, the primary data enter into the space K with a constant sampling rate used in the center area and the surrounding area; and the center area having a first sampling-point density is sampled and the surrounding area is sampled with a second sampling-point density which is smaller than the first density so as to generate a magnetic resonance data file. Therefore, the group of data points expressing the sampled space K can be obtained as the data file outputted from the computerized process in the mode of allowing establishing an image in the contents of the data file.

The invention relates to a method and device for displaying an image, and belongs to the technical field of graphical display. The method comprises the steps that target pixel point density is determined according to equipment information of display equipment, the rendering resolution ratio is calculated according to the target pixel point density, image pixels are rendered according to the rendering resolution ratio, and the resolution ratio of the image corresponding to the image pixels obtained through rendering is amplified into the display resolution ratio from the rendering resolution ratio and then displayed in a screen; after the proper rendering resolution ratio is selected, the image obtained after the image pixels are rendered according to the rendering resolution ratio and an image obtained after the image pixels are rendered according to the display resolution ratio have a small visual difference, a large quantity of processing resources and electricity can be saved through the image rendered according to the rendering resolution ratio relative to the image rendered according to the display resolution ratio, and therefore the effects of improving rendering efficiency and saving the processing resources and electricity resources of display equipment on the premise of guaranteeing the visual effect of the image are achieved.

Belonging to the technical field of metal surface treatment, the invention provides a method for improving metal surface wettability by high energy beam texturing. The method includes: firstly adopting high energy beam (electron beam and laser beam) to texture a kovar alloy surface to form regularly arranged different texturing shapes so as to obtain a metal surface with different roughness and texturing point density; then oxidizing the metal surface to obtain an oxide layer with certain component; and finally heating borosilicate glass to a temperature above the softening temperature by a sessile drop technique, and testing the wettability of glass on the metal surface. High energy beam texturing promotes wetting spreading of molten glass on the metal surface, increases the contact area between glass and metal, and effectively promotes mechanical-chemical combination of glass-metal.