139 results about "Grid deformation" patented technology

The invention relates to a rapid generation method for facial animation, belonging to the image processing technical field. The method comprises the following steps: firstly detecting coordinates of a plurality of feature points matched with a grid model face in the original face pictures by virtue of an improved active shape model algorithm; completing fast matching between a grid model and a facial photo according to information of the feature points; performing refinement treatment on the mouth area of the matched grid model; and describing a basic facial mouth shape and expression change via facial animation parameters and driving the grid model by a parameter flow, and deforming the refined grid model by a grid deformation method based on a thin plate spline interpolation so as to generate animation. The method can quickly realize replacement of animated characters to generate vivid and natural facial animation.

The invention discloses a tree leaf modeling method based on point cloud data. The tree leaf modeling method comprises the following steps of preprocessing, namely denoising, smoothing and the like, the tree leaf point cloud data acquired by a three-dimensional laser scanner; then extracting boundary points and vein points of the point cloud data, and reducing the point cloud data; constructing a grid model of tree leaves by using Delaunary triangular gridding, and drawing a vivid tree leaf model by a texture mapping method; and finally selecting the vein points as control points, and generating the tree leaves of different forms by a Laplacian grid deformation method. By the tree leaf modeling method, the boundary points and the vein points in the point cloud data can be accurately extracted and can be retained in a process of reducing the data, so that the extremely vivid tree leaf model with rich details can be reconstructed; and furthermore, forms such as curling and sereness of the tree leaves under the conditions of high temperature and water loss can be simulated.

The invention relates to a method for reconstructing a high-resolution three-dimensional human face model from some human face pictures in different angles, which comprises the following steps of: starting from two more front human face images and solving internal and external parameters of a camera and three-dimensional coordinates of an angle point by applying a motion reconstructing structure technology based on beam adjustment on the basis of the stereomatching of angle point detection (containing characteristic point); repeating the process for the human face images in adjacent angles toobtain camera parameters corresponding to all human face images; dividing the human face images based on the characteristic point and registering a human face template to the practical human face position according to the three-dimensional characteristic point; by solving the problem of nonlinear energy optimization for maintaining the consistency of human face model details and the images many times, carrying out grid deformation on the human face template to obtain the reconstructed high-resolution three-dimensional human face model; and finally, by generating a texture map, a weight map and an overall texture map corresponding to each image, carrying out texture mapping on the reconstructed three-dimensional human face model to generate a real human face.

The invention provides a three-dimensional model reconstruction method based on grid deformation, which is used for constructing a training sample set and comprises the following steps of: manufacturing discrete view angle pictures of a plurality of models and corresponding three-dimensional point cloud data; setting a deep learning network model based on the graph convolutional neural network, wherein the deep learning network model based on the graph convolutional neural network comprises a discrete view angle feature fusion module and a grid deformation module, and the output of the discrete view angle feature fusion module is connected with the input of the grid deformation module; setting a loss function, and based on the training sample set, training a deep learning network model based on the graph convolutional neural network; and inputting the discrete view angle picture of the to-be-reconstructed object to the trained network model, performing automatic reconstruction of the three-dimensional grid model, and evaluating the precision. According to the method, the discrete view angle picture and the three-dimensional point cloud data set of the object are learned and trained, and automatic three-dimensional grid model reconstruction can be carried out on objects of different types and sizes stably and accurately.

The invention discloses a self collision detection method based on a triangle mesh deformation body, comprising the steps of (1), constructing a data structure based on a hierarchical hounding volume (BVH); constructing an xBVH (expanded bounding volume hierarchy); constructing an SCTT (self-collision test tree)); optimizing star-shaped outline; (2), pre-processing self-collision detection based on the star-shaped outline; (3), performing self-collision test based on the star-shaped outline in real time. The method can detect the self-collision phenomenon during the deformation of the triangle mesh deformation body effectively in real time, accurately locates collision generation point and updates the collision information in real time.

The invention discloses an image splicing method based on grid deformation, relating to the technical field of image splicing. The method includes the following steps of S1 respectively extracting SIFT characteristics of two space adjacent images, and matching the characteristics; S2 performing iterative computation by means of an RANSAC algorithm and screening characteristic point pairs; S3 estimating the global projective matrix and performing global projective transformation; S4 by means of Delaunay triangulation, constructing a dense triangular grid for an overlapping region and constructing a sparse grid for a non-overlapping region; S5 establishing the grid deformation energy function and optimizing the global projective registration; and S6 fusing the images to produce a wide-view-field image. The dense triangular grid represents the overlapping region and the sparse triangular grid represents the non-overlapping region of the image, so that compared with the APAP method, the whole image uses dense and same matrix grids, the algorithm efficiency is greatly improved. Meanwhile, the grid deformation can make full use of the parallel and high-speed operation performance of the CPU, and the splicing speed can be greatly improved.

The invention belongs to the field of digital and geometric processing in computer graphics, and in particular to a 3D grid model deformation editing method based on the local rigidity principle. The invention aims at providing a deformation editing method having a fine deformation effect and a satisfactory deformation interaction speed, which is used for model reuse. The method uses grid segmentation and manifold Laplace transform to increase the local rigidity-based deformation editing speed and comprises the following steps: segmenting a 3D model into multiple parts by the grid segmentation, deforming parts which need to be deformed, and splicing the multiple parts, thereby greatly increasing the deformation speed and simultaneously avoiding distortion conditions at the joints. Besides, the manifold Laplace transform can greatly reduce the dimension of linear system of equations of corresponding deformation, thereby achieving higher result controllability.

The invention discloses an aircraft multi-body separation CFD simulation method and system based on a hybrid power grid technology. The method comprises the following steps of dividing an aircraft multi-body into the CFD numerical simulation of multiple stages from separation start to separation end; and completing the CFD numerical simulation and splicing of each stage sequentially according toa grid deformation technology and a grid reconstruction technology; and combining a grid deformation technology and a staged grid reconstruction technology. The aircraft multi-body separation CFD numerical simulation method based on the hybrid dynamic grid technology can give full play to the advantages of high calculation efficiency and high calculation precision of thegrid deformation technologyin a small displacement range, also can give full play to the advantage that the staged grid reconstruction technology can effectively improve the grid quality in a staged manner under the conditionof large displacement, and improves the calculation precision, so that the method can be effectively applied to the research on the multi-body separation problem of the unsteady, high-Reynolds-numberand large-displacement aircrafts.

The invention relates to a method for deforming a smart graph-driven grid image. In the method, global deformation parameters of the image are mapped to a two-dimensional grid to drive the grid to deform; the grid drives an embedded image of the grid to deform so as to solve the problems of non-accurate image deformations similar to cartoon animation deformations; and a user can quickly acquire an image deformation result through the interaction control of a control point on a smart graph. The method adopts a smart graph-based deformation driving template which has the characteristics of an embedded deformation rule and multi-component coordinative deformation, and can automatically generate appropriate grid driving parameters according to the global deformation parameters so as to generate a grid effect in real time. Besides, by performing cross regulation on different deformation weight coefficients, the method can control the deformation intensity. The method can acquire a two-dimensional grid deformation result of the embedded deformation rule at an interactive real-time speed, and can conveniently and quickly generate a deformation effect of a two-dimensional cartoon animation image by further solving the coordinate mapping and the gray mapping of an image pixel under grid driving.

The invention relates to a three-dimensional grid deformation method based on surface area maintenance and provides an effective, fast and vivid deformation method for three-dimensional grid objects aiming at the deformation problem of a three-dimensional model of a soft object, which belongs to the field of computer application, in particular to the technical field of computer graphics and virtual reality. In the method, various forms of deformations are seen to be respectively composed of basic bending deformations, the local regions of the basic bending deformations are independently calculated, and a global deformation result is obtained through the joint of the regions; deformation regions are divided according to control curves, and a basic grid deformation algorithm irrelevant to an original grid model is proposed through separating and synthesizing basic deformation grids and detail grids; damped oscillation curves are used to simulate surface wrinkles at the bent and deformed inner sides of the soft object, and the vertex column length of a basic model is maintained to realize the surface area maintenance and improve the third dimension of grid deformation so as to realize the deformation of a three-dimensional grid model.

The invention relates to a method and a device for correlated micro-imaging of a frozen light microscope and a frozen electron microscope, in particular to a method and a device for correlated imaging of a frozen light microscope and a frozen transmission electron microscope, including an optical microscope frozen object stage device used for optics-electron correlated micro-imaging and a corresponding correlated imaging method. By adopting the method and the device, optical micro-imaging at extra-low temperature (below minus 170 degrees) can be achieved, and frozen electron micro-imaging of the same samples in the same areas can also be achieved. The method and the device can be widely used to correlate various types of inverted optical microscopes and most transmission electron microscopes at the market, can achieve correlated imaging fast, conveniently and accurately, prevent ice crystals from forming on surfaces of the samples to the maximum extent, avoid problems of grid deformation and carbon film fracture, and can be widely applied to related research of cytobiology, neurobiology, biological medicines, etc.

The present invention discloses a face relief geometric modeling method, and belongs to the field of relief modeling. The problems are solved that current portrait relief modeling is low in efficiencyand poor in automation. The method comprises the following steps of: performing face key feature point location for an input single face image, and obtaining face image feature points; based on a BFMparameter face model, constructing an initial 3D face; based on a Bi-Laplacian constrained point displacement method to perform shape optimization of the initial 3D face, and generating a 3D face after shape optimization; performing height field optimization of the 3D face after shape optimization based on a relation of the face image illumination intensity and the 3D face geometric normal, and generating a 3D face after height optimization; and performing linear compression of the 3D face after the height field optimization, generating an original 3D face relief, performing geometric detailoptimization of the original face relief through a Bi-Laplacian grid deformation method based on key point constraint, and generating a face relief with rich geometric details.

The invention relates to a three-dimensional grid model digital watermarking method based on spherical parameterization. The existing digital watermarking technology mainly aims at the media data patterns such as still pictures, video streams and audio streams and the research works on the watermarking technology of three-dimensional geometric model data are less. The method of the invention comprises the following steps: utilizing the method of grid global spherical parameterization to obtain spherical harmonic and analytical coefficient of the grid, embedding a watermark in the harmonic and analytical coefficient, and then perform the corresponding inverse transformation to obtain the grid embedded with the watermark. The method also solves the grid deformation problem caused by sampling and watermark-embedding, and the amplification of the grid watermark information in watermark-extracting process and the specific coding strategy of the watermark are beneficial to the extraction of the watermark. The method for extracting the watermark does not require the original grid and pretreatment, and can resist various attacks such as noise-adding, smoothness, enhancement, rotation, translation, scaling, resampling, clipping and some combined attacks.

The invention discloses a design method of a wing type of a rotor wing of a micro-miniature type rotor wing UAV and a product, and the design method combines an efficient optimization algorithm basedon the agent model, a shape parameterization method based on the free deformation technique, a grid deformation method based on the radial basis function and an aerodynamic performance computing method based on the average Reynolds equation. Firstly, the design condition is determined, the incoming flow states, namely, the incoming flow Mach number, the Reynolds number and the angle of incidence,of the wing type are determined according to the main operation condition of a propeller and the radial position of the wing type on the blades; then the design index is determined; a lift-drag ratioas large as possible is obtained. According to the method, an Eppler 387 is taken as the datum wing type, the wing type whose whole curvature of the upper surface protrudes upward, front section of the curvature of the lower surface is concaved downward and rear section protrudes upward is designed, the relative thickness is small, the upper surface of the rear section is relatively flat, the whole curvature is large, the front section of the lower surface is concaved remarkably, the wing type has low total resistance coefficient and high lift coefficient, and accordingly the wing type has high lift-drag ratio and the aerodynamic efficiency is improved.

The invention relates to a grid parameterization-based structure multi-disciplinary design optimization method. According to the method, analysis grids of all disciplines are parameterized by utilizing a grid deformation technique, and the consistency of grid changes of all the disciplines at a coupled interface is guaranteed; the multi-disciplinary design optimization of a structure is realized on the basis of grid parameterization, so that the problems caused by needing to regenerate a geometric model and divide grids during each time of optimization iteration in the traditional optimization design method are effectively avoided.

The invention discloses a non-rigid multimode medical image precise registering method. The non-rigid multimode medical image precise registering method includes the following steps that normalization processing is performed on a reference image and a floating image. A pulse sending cortex model is used for processing so as to obtain two ignition mapping images. A Sobel operator is used for respectively abstracting edge features of the two ignition mapping images to obtain corresponding gradient images. A sum of squareddifferences of the two gradient images is calculated out. Finally, based on a free grid deformation model and the sum of squareddifferences a target function is determined. A quasi-Newton method is used for performing iterative optimization on the target function to obtain optimal deformation parameters. According to the non-rigid multimode medical image precise registering method, the pulse sending cortex model and the sum of squareddifferences are used for performing non-rigid multimode medical image registering and registering precision is greatly improved.

The invention discloses a content perception binocular image zooming method based on grid deformation. The method comprises the following steps: A, inputting an original left-eye view and an original right-eye view, and setting the resolution of an object image; B, respectively constructing uniform quadrilateral grids covering the image for the left-eye view and the right-eye view; C, respectively calculating grid-grade importance degree graphs of the left-eye view and the right-eye view; D, constructing a grid-grade linear characteristic set of the left-eye view and the right-eye view; E, according to the grid-grade importance degree graphs, establishing grid zooming energy functions; F, according to the grid-grade linear characteristic set, establishing linear characteristic constraints, and carrying out grid zooming energy function minimizing operation by use of least squares to obtain a left-eye view object grid and a right-eye view object grid after zooming; and G, mapping the original left-eye view and the original right-eye view respectively to an object grid by use of a mapping method, and outputting a final left-eye view and a final right-eye view. According to the invention, the linear characteristic of the zoomed image can reserved, important objects are prominent, and stereo information of a binocular image is maintained.

The invention discloses a volumetric mesh deformation method. The method is used for the interactive design of a simulation system for a hump nose plastic surgery; in the system, the Laplace coordinate-based deformation method on surface meshes is popularized to the volumetric meshes, and a high-quality volumetric mesh deformation effect is achieved in a simple and convenient interactive operation mode, so that the geometric detail characteristic and model volume are kept invariant as much as possible; meanwhile, the influence of non-uniform material parameters on deformation is considered fully to achieve a similar effect of physical deformation. In the simulation system for the hump nose plastic surgery, the original input data is computed tomography (CT) scanning volumetric data of patients and is imported into an image segmentation module and a three-dimensional model reconstruction module.

The invention discloses a horizontal surface fitting method based on quadric error metrics (QEM), comprising the steps of: inputting and preprocessing data; ensuring a fitting area; computing the quadric error metrics matrix of a sampling point; distributing the sampling point to each grid peak to be adjusted; and adjusting the grid peak with the quadric error metrics matrix. The horizontal surface fitting method based on the QEM can deform the reconstructed horizontal surface according to the input sampling point and a fault surface, so that the deformed horizontal surface is more in accordance with the shape of the input point. Compared with the existing grid deformation method, the method has convenient use and fast speed, and can better solve the problem of the local deformation of a grid mode.

The invention provides a method for predicting the flow-induced vibration characteristic of a large-deformation super-elastic structure, and belongs to the technical field of biomechanics and system coupling simulation thereof. The structure and a surrounding flow field thereof are taken as a three-dimensional fluid-solid coupling system, and one set of coupled solution method based on an immersed boundary method is designed, so that the flow-induced vibration characteristic and unsteady flow field characteristic of the super-elastic structure are obtained. In the method, two sets of grids are adopted, an entire coupling system area consisting of fluid and the structure is solved by adopting a Cartesian grid under the description of Euler, and a solid area is solved by using an aptamer curvilinear grid under the description of Lagrange. In the method, a moving grid technology is not used, so that the problems of grid deformation, geometric non-conservation of discrete grids and the like are avoided, and the problem of mutual action of a large-deformation flexible structure and the fluid can be effectively solved. Particularly, the method can be widely applied to coupling motion of a flexible biological structure and the fluid.

The invention discloses a multi-view three-dimensional reconstruction method, and the method comprises the following steps: based on an end-to-end deep learning framework, taking a plurality of colorimages at different visual angles as network input, and taking a reconstructed three-dimensional grid model as output; according to the network, firstly, extracting multi-view fusion features of different scales by using a multi-level fusion feature extraction module; and based on the fusion features of different scales, utilizing a grid deformation module to deform the input initialized ellipsoidal grid model, and reconstructing a three-dimensional grid model corresponding to the input image. According to the method, multi-view information is fully utilized, and higher reconstruction precision and a better reconstruction effect are achieved.

The invention provides a grid deformation optimization method for cutting simulation of a deformable object in the virtual surgery. Multiple tasks are subjected to parallel processing by adopting geometric optimization and topology optimization combined with a multi-threaded approach, so that the problem that morbid cells occur in the cutting simulate process is solved. The grid deformation optimization method comprises the four steps: step 1, target cell searching: searching grid cells required to be processed according to the grid quality; step 2, grid optimization preprocessing; step 3, grid topology optimization process; step 4, grid geometry optimization process. The step 2, the step 3 and the step 4 use multi-threaded parallel processing. The grid deformation optimization method provided by the invention has the benefit that while the grid quality is improved, the number of grids can be reduced, so that the efficiency and the stability of grid model deformation calculation can beeffectively improved.

The invention discloses an aluminum honeycomb ultrasonic cutting and impacting integrated machining method. The method comprises the following steps that an aluminum honeycomb to be processed is fixedto a machine tool clamp, an ultrasonic vibration device is installed on a machine tool main shaft, a circular slice knife with specific lower end face tiny patterns is installed on the ultrasonic vibration device, and the end face runout of the lower knife face of the circular slice knife is measured and adjusted. According to the needed aluminum honeycomb surface shape, a knife walking path is determined; the ultrasonic vibration device is started to enable the circular slice knife starts to be vibrated, the machine tool main shaft is started to enable the circular slice knife to rotate, andthe aluminum honeycomb to be processed is processed according to the knife walking path. Compared with an exiting high-speed milling machining method, cutting force is obviously reduced, the processed aluminum honeycomb workpiece is smaller in hole grid deformation, burrs, bruises and other machining defects are obviously reduced, and the surface evenness is high. The aluminum honeycomb surface which can be ultrasonically cut according to the needed surface shape, has the wall width increased and has the specific surface microtopography can be obtained, and later-period honeycomb adhesion isfacilitated.

The invention discloses an aerofoil aerodynamic drag reduction method based on an improved radial basis function deformation algorithm, and aims to improve the automation degree of aerofoil drag reduction design, further reduce the wind drag coefficient of an aerofoil and improve the drag reduction optimization efficiency. According to the technical scheme, the method comprises the steps of usingall nodes on the geometric boundary of the airfoil profile as the design variables; establishing an airfoil aerodynamic resistance function related to the resistance variable d; solving the minimum value problem of the aerodynamic resistance function f (d, S) about the design variable group by adopting a sequence least square programming algorithm; and obtaining an optimal displacement sequence ofNw inner boundary points on the inner boundary of the grid, and performing aerodynamic drag reduction deformation on the airfoil grid by adopting an incremental solving RBF grid deformation algorithmto obtain an optimal wind drag coefficient or airfoil grid and airfoil geometry of which the airfoil drag reduction reaches the best result within the maximum iteration step number. The method can besuitable for various types of grids, the automation degree of the airfoil profile drag reduction design can be remarkably improved, the drag reduction optimization efficiency is higher, and the result is more accurate.

The invention discloses a three-dimensional structured model reconstruction method based on any view angle pictures. The method comprises the following steps of 1, collecting pictures, and forming a training data set; 2, segmenting object parts of the picture to obtain a bounding box of each part; 3, constructing a deep convolutional network model, and extracting a corresponding depth image from the image; 4, constructing a deep network model, and decoding the structural representation of the object; and 5, constructing and training a deep three-dimensional mesh deformation network, and deforming the bounding box into a three-dimensional model with a good structure. According to the method, the object structure representation is deformed, and a topology self-adaption method is used, so a problem that the topology is not changed when a general graph is used for convolution can be solved, and geometric details and the structure information of object recovery are ensured.

The invention discloses a spatial discrete grid point reorganization and integralization method, belongs to the field of automatic grid generation in finite element numerical simulation, and aims to eliminate the limitation of finite element grid automatic generation and grid deformation technologies in some problems. Therefore, full-automatic generation of the finite element grid with the complexshape under local shape change is realized by adopting a structure and non-structure mixed mode. However, the unstructured grids are arranged disorderly, so that discretized grid points arranged disorderly need to be reorganized to form a data structure capable of being used by a grid algorithm; the method is suitable for quadrilateral structure grids, discrete grid points are classified throughthe connection relation of the grid points, adjacent grid points are searched step by step in a recursive search mode, and spatial discrete grid points are reorganized line by line according to the mode in a grid block-by-grid block-by-line mode.

Systems (100) and methods for three-dimensional polygonal garment mesh (1402) deformation and / or layering for garment fit visualization. A deformation engine (120) receives at least one garment mesh (1402) fitted to a template body mesh (1404) and deforms the garment mesh (1402) to a target body mesh (1306) according to a geometrical deformation algorithm. A layering engine (130) receives plural garment meshes (1402) that are separately fitted to a target body mesh (1306), and deforms the plural garment meshes (1402) according to an iterative layering process that deforms each individual garment mesh (1402) according to a layering order while preventing intersections between other garment meshes (1402) and the target body mesh (1306).

The invention provides a human bod motion animation generating method of a two-dimensional virtual figure. The human body motion animation generating method comprises the steps of shooting a real person motion video; extracting an initial frame image of the video; detecting the angular point of the initial frame image; calculating a sparse characteristic point light stream frame by frame; calculating 2D grid deformation; calculating a modal grid and a weight sequence; editing the modal grid and the weight sequence; using an isomorphic 2d grid to conduct animation rendering on the virtual figure. According to the technical scheme, compared with a purely manually made animation, since motions come from the real person video, the animation is more vivid, and particularly, it is very difficultto achieve the authenticity of the deformation and the rhythm randomness of the motions through a manual method; the 2d figure has a certain stereoscopic effect, the animation effect can be adjustedaccording to requirements through manual modification simply with the isomorphic grid, the same motion data can adapt to different figures of different body types, different skins, different clothes and different icons, and when the animation is applied, the real-time calculation amount is small.

The invention discloses an overlapped grid disturbance domain updating method for aircraft multi-body separation simulation. The method comprises the steps that a wall distance algorithm is simplified by employing an implicit assembly method based on the attribute characteristics of a wall distance marking unit, so that the grid assembly efficiency is improved; secondly, under the framework of a disturbance domain updating method, numerical simulation of the overlapped grids is realized, so that only units in a non-convergent disturbed region are subjected to interpolation operation, and the calculation amount of the interpolation operation of the overlapped grids is reduced; and thirdly, a novel overlapping grid information exchange method is established, and the mode that information is transmitted based on grid deformation and encryption in a large flow gradient area and information is transmitted based on flow gradient interpolation in a small flow gradient area is achieved, so that the accuracy of the overlapping area is improved, and the isolated point problem is avoided. According to the method, the calculation efficiency of numerical simulation of the multi-body separation problem of the aircraft can be remarkably improved, and the problems that the numerical precision is lost in a large-flow gradient grid overlapping region, and isolated points exist are solved.