最新刊期
卷 14 ， 期 9 ， 2009
- 摘要：Probabilistic graphical models (PGM) is widely applied in visual information processing for the intrinsic uncertainty in visual information, and followed by a group of researchers recently. PGM offers a number of advantages for resolving variety problems in visual information processing, in which Markov Random Field (MRF) can be used to model pixel level information processing based on the development of high efficiency inference algorithms. In this paper, we shortly introduced concepts of PGM, and gave detailed analysis and discussion on the definition, features and inference of MRF followed by typical examples of its application in computer vision.关键词：markov random field(MRF);probabilistic graphical model(PGM);bayesian network;belief propagation(BP);graph cut(GC);energy minimization6141|354|0更新时间：2024-05-07
- 摘要：Probabilistic graphical model(PGM) and its application have become a new hot-spot as a challenging research. It provides an important means for resolving the uncertainty of intelligent information field. Although PGM is still in its development, the application of intelligent information processing of images and videos based on PGM has emerged and many effective algorithms has emerged which provide a new strategy to solve for the traditional problems. Based on the three important expressions, the characteristics and the main technology of PGM,we analyze and introduce the primary technology of intelligent information processing of images and videos based on PGM. Finally, we discuss the disadvantages and development trend of PGM.关键词：probabilistic graphical model(PGM);bayesian network;Markov network;hidden Markov network;image;video5706|331|0更新时间：2024-05-07
- 摘要：It has become evident that the commonly used two-dimensional tensor product wavelet bases are not optimal for representing signals that resemble images. This motivated a variety of schemes beyond wavelets, such as ridgelets, curvelets, contourlets, and wedgelets. Contourlet transform provides an efficient representation for two-dimensional piecewise smooth images, and constructed in discrete domain. In this paper, contourlets and hidden Markov model using contourlet transform are discussed, and the deep insights on the keys to understanding the contourlet transform are stated in details. The applications of contourlets, comparing with wavelets, are also introduced, and comment on the potential of contourlets for these applications in the future is given.关键词：wavelet transform;contourlet transform;natural image;hidden Markov model(HMM)6015|350|0更新时间：2024-05-07
- 摘要：In order to more effectively segment noise-corrupted brain MRI images, a kernelized clustering algorithm using fuzzy Markov random field (MRF) model is proposed. The proposed algorithm is implemented by incorporating the MRF based spatial constraints as a regularization term to the objective function of the kernelized fuzzy C-means clustering（FCM）. The spatial connectivity modeled by the Gibbs distribution is actually formulated as a normalized Gaussian radius basis function (GRBF), and very similar to the kernel function used to measure the intensity feature of image data. Due to the introduction of fuzzy information in the spatial constraints, the MRF and GRBF based clustering algorithm improves the segmentation model and usually outperforms the conventional intensity based FCM method and the corresponding kernelized clustering method. The modified algorithm can incline the solution to a piecewise smoother segmentation result. Experiments on synthetic data, simulated and real clinical MR images and the result comparisons with ground truth show the proposed algorithm is superior to its rivals and is effective to segment MR data corrupted by noise.关键词：MR image segmentation;kernelized clustering;fuzzy Markov random field;spatial constraints5924|293|0更新时间：2024-05-07
- 摘要：Bone segmentation in knee MRI can be regarded as the groundwork of segmenting and analyzing soft tissue in knees. Usually this task is time-consuming and needs human intervention. To solve this problem automatically and rapidly, a multi-scale MRF is introduced into knee MRI segmentation in this paper. Gaussian mixture model is firstly built as the statistical model for the intensity image, with an estimation of index number using MDL. In the phase of building multi-scale MRF model, non-iterated computing based on causality between scales is implemented, where statistical information is transferred from fine scales to coarse scales and MAP of every pixel is computed from coarse scales to fine scales. As a result, fast and unsupervised bone segmentation on knee MRI can be achieved. The experiments show that the temporal cost of segmenting knee bones based on multi-scale MRF is extremely low and the segmentation error can be comparable to manual segmentation by medical experts. In conclusion, the work presented here accomplishes fast and accurate segmentation on knee MRI of low SNR through building a multi-scale MRF model. Future work can be extended to further cartilage and meniscus segmentation.5560|320|0更新时间：2024-05-07
- 摘要：To deal with the uncertainties of the particle filter of the motion model, an improved particle filter EMPF (expectation-maximization particle filter) is proposed. The target states could be estimated more accurately by combining the EM and the PF algorithms, in which the parameters of the motion model are estimated and later confirmed by the EM algorithm. Thus the target states could be estimated more accurately. And the experiment results show that when the target was turning, the algorithm can improve the estimation of the target’s motions dramatically.关键词：target tracking;particle filter;EM algorithm;motion model;turn maneuver5685|290|0更新时间：2024-05-07
- 摘要：Getting exact human position under occlusion is a key problem to object recognition across multiple cameras with overlapped views.The problem of human segmentation was converted to maximize the posteriori estimation by constructing a human model and a Bayesian model. And then the same objects were matched in different views on the least distance principal by taking the human axis as a feature. Experiments show promising results on human segmentation and recognition in crowded situations and the accuracy rate is high.关键词：Bayesian model;object recognition;crowd segmentation;human model5257|294|0更新时间：2024-05-07
- 摘要：To solve the problem that the clothes variance or taking goods may affect the result of gait recognition, a new gait recognition method based on variance of dynamic region is proposed in this paper. Firstly, through the background subtraction and shadow elimination, human motion silhouettes are obtained, which will be normalized in terms of location and scale. Next, the dynamic regions are obtained using gait energy image and threshold segmentation, and gait feature is extracted from the dynamic region using the sector region distance transform. At last, maximum entropy markov Model is used to model the gait sequences of each people and implements recognition based on probability graph. The method is evaluated for the CASIA gait database and receives comparatively high correct recognition rate. The experimental results show that our approach is robust in the case of clothes variance and taking goods.关键词：gait recognition;dynamic region;sector region distance transform;maximum entropy Markov model5159|271|0更新时间：2024-05-07
- 摘要：The goal of digital image restoration is to reconstruct an original scene from a degraded observation. This recovery process is critical to many image processing applications. The digital image restoration approaches has been thoroughly studied in recent years. This problem, however, still has numerous research possibilities. In order to give people a comprehensive knowledge of digital image restoration, some typical approaches are presented and discussed in this paper based on 95 references selected from various literatures in this field. We first describe problems in the digital image restoration and discuss its mathematics background. And then, the review is divided into two parts and discussed thoroughly, according to the development of digital image restoration approaches. One is the classical image restoration approaches, and the other is the modern ones. The former is developed based on the objective that provides an overview on the basic principles and methodologies behind the existing algorithms, and the later is arranged to examine the current trends and the potential of this challenging problem. After the survey is discussed in detail, we make a conclusion for this paper and follow by addressing 7 key issues which remain open in this field.关键词：digital image restoration;blur identification;neural network;regularization;wavelet;support vector machines6479|448|0更新时间：2024-05-07
- 摘要：A new method is proposed in this paper to improve the traditional histogram equalization, mainly to solve the problem of color distortion of the color images caused by the direct usage of histogram equalization. This algorithm firstly divides the histograms of three channels of R, G, and B twice based on the mean of the grey levels and the principle of equal area. Then it equalizes the sub-histogram respectively. Finally, the processed images of each channel are merged by calculating the proportion of the three channels in the original image. The experiments indicate that the proposed method is quite effective in processing color images.关键词：histogram equalization;image enhancement;histogram segmentation;color image4638|481|0更新时间：2024-05-07
- 摘要：Steganalysis technique is of great importance to network information security and how to search and detect secret messages transferred in network is crucial and practical to safeguard national security. Against a variety of DCT coefficients distribution model proposed by the scholars at home and abroad,this paper introduces the α-stable family models of the image’s DCT coefficients. Take into account real statistical properties, this paper also describes the α-stable family models of cover image’s DCT domain by the numbers. And we also testifieed by the experiment that image’s DCT coefficients satisfy α-stable family distribution but GGD(generalized Gaussian distribution) and Gaussian distribution and Lapalacian distribution. The α-stable family models have enough flexibility, and their shape of distribution changes with characteristic index α.At same time, this paper designs a new processor to blindly hide information detection using Cauchy receiver operating machine based on project needs: facility, practicality, feasibility and performance good. This detection performance is better than GGD’s detection performance. Compared to the reference ［8］, our model performance enhanced.The operating speed is increased by scores of times.关键词：steganalysis;α-stable family models;receiver operating machine;ROC curves3286|248|0更新时间：2024-05-07
- 摘要：To realize fast and robust electronic image stabilization, an algorithm using phase correlation in single-quadrant Fourier-Mellin domain to estimate similarity motion parameters is presented. First, according to the property of origin symmetry of the Fourier magnitude spectrum and the idea of image block matching in spatial domain, a novel method of single-quadrant Fourier-Mellin transformation(SQFMT)is proposed, which applies log-polar transformation in frequency domain to map the single-quadrant magnitude spectra from Cartesian coordinate space to log-polar one. The similarity transformation parameters are estimated using SQFMT combined with phase correlation method. In contrast to the approach based on the standard Fourier-Mellin transformation (FMT), our algorithm yields an effective solution in computational performance, and achieving consistent accuracy. The experimental results show that our algorithm can achieve a reduction of 75% run time on average, with a small accuracy increases comparied with standard method.关键词：electronic image stabilization;SQFMT;phase correlation;similarity motion3440|241|0更新时间：2024-05-07
- 摘要：With superior mathematical characteristics, PDE and variational image de-noising methods achieve better results than traditional methods. Many models deal with de-noising problems only. A new variational model incorporating point spread function information was constructed to deal with de-noising and de-blurring problems concurrently. Kacˇanov linearization technique was used to solve the new model. Experiments and related data proved the effectiveness of the model.关键词：variational calculus;point spread function;image de-noising;image de-blurring3403|262|0更新时间：2024-05-07
- 摘要：Improved embedded zero-tree wavelet (EZW for short) algorithm of dominant and subordinate pass mix-coding is presented. The subordinate pass of big coefficients that belong to a previous threshold becomes the first step during the encoding process. The dominant pass and the subordinate pass that constituted by the new big coefficients are combined to a new dominant pass. It makes encoding and decoding effective. Experimental result shows that compared to the traditional EZW, the improved algorithm can increase the peak signal to noise radio (PSNR for short) of image compression.关键词：JPEG2000;improved algorithm;mix-coding;image compression;wavelet3292|226|0更新时间：2024-05-07
- 摘要：Vector quantization(VQ) is an efficient approach of lossy data compression. The performance of the fast codeword search algorithm in VQ determines its encoding time. Absolute error inequality(AEI) algorithm is a standard fast codeword search algorithm, in which the initial matching codeword search is based on Minimax method. However, the computation cost that is required at this step in AEI algorithm is too much. Aimed at solving this problem, we propose an improved method for searching the initial matching codeword that is named as Partial Minimax Method. The proposed method guarantees the found initial matching codeword is the same as the standard AEI method and the PSNR performance of AEI method has no degradation. Because it can significantly reduce the computational cost for searching the initial matching codeword, the proposed method can speed up the standard AEI method effectively.关键词：vector quantization;fast search;AEI algorithm;initial matching codeword3711|252|0更新时间：2024-05-07
- 摘要：Based on the research and analysis of the H.264/AVC classical rate control algorithms, a new frame-rate control algorithm is proposed in this paper. The algorithm takes full advantage of the complexity of frame and the target buffer level to optimize the bit allocation, using a kalman filter method to estimate mean absolute difference (MAD). Comparing to the previous rate control algorithms, the algorithm can allocate the bits more rationally, and forecast MAD more accurately, thereby improve the accuracy of estimating the quantization parameter QP. The experimental results show that, compared to JM8.6 original algorithm, the proposed rate control algorithm can improve the precision of rate control, and heighten overall image quality at the same time.关键词：H.264;rate control;complexity;kalman filtering3546|225|0更新时间：2024-05-07
- 摘要：3D mesh models are high sensitive to the magnitude of their embedding watermarks, and most watermarking algorithms only use low-magnitude embedding method to avoid serious distortion of visual-effect, but unfortunately,it would degrade robustness. In order to compromise the robustness and the transparency of watermarked 3D meshes, a zero-watermarking algorithm that modified nothing of 3D mesh data is presented. After calibrating mesh geometric data, mesh vertices are divided into some blocks according to their bounding-box, and then apply 3D-DCT to integrate the energy in transformed domain. Watermarking signals are constructed by some bigger DCT coefficients and registered in the database of IPR to obtain copyright protection. Original 3D mesh data are not needed when detecting watermark. Experimental results show the watermark constructed by presented algorithm can resist vertex reordering, translating, rotating, uniformed scaling, and show robustness against adding noise, mesh simplifying, mesh filtering, and adding a secondary watermark.关键词：3D watermarking;mesh watermarking;zero-watermark3822|262|0更新时间：2024-05-07
- 摘要：In order to resist geometrical attacks, an object-based video watermarking algorithm using Zernike moments and image normalization is proposed in this paper. Rotation invariance is achieved by taking the magnitude of the Zernike moments. Image normalization method is used for scale and translation invariance. Though watermark signal can be embedded by modifying the Zernike moments of the cover image, the reconstruction procedure will suffer the fidelity degradation. Also, the reconstruction procedure requires Zernike moments with high order and this leads to a heavy computation load. In order to solve these problems, zero-watermarking technique is employed. Instead of embedding watermark, zero-watermarking technique extracts some essential characteristics from the host signal and uses them for watermark detection. Experimental results show that the scheme is robust against rotation, scaling, as well as a variety of common manipulations such as lossy compression, filtering and additive noise.关键词：Zernike moment;zero-watermarking;video object;image normalization3711|355|0更新时间：2024-05-07
- 摘要：Linear discriminant analysis is a way of feature extraction and dimension reduction. It is widely applied in face recognition, speech recognition, and handwriting recognition etc. However, many linear discriminant analyses are "hard" ones and every data point belongs to one class or another class strictly. In this paper, a fuzzy uncorrelated discriminant transformation (FUDT) is proposed based on uncorrelated discriminant transformation (UDT). FUDT is a supervised learning method with fuzzy set and its discriminant vectors satisfy the equation of generalized rayleigh quotient. Furthermore, the projection of samples to fuzzy uncorrelated optimal discriminant vectors is uncorrelated by FUDT. The experimental results show that FUDT is better than UDT in extracting the feature of SAR images which come from MSTAR.关键词：linear discriminant analysis;uncorrelated discriminant transformation;fuzzy uncorrelated discriminant transformation3437|270|0更新时间：2024-05-07
- 摘要：A novel feature extraction method using block-based independent component analysis (BICA) is proposed in this paper. BICA partitions the facial image into a few blocks, reducing the influence of some factors such as lighting condition and facial expression on face recognition. The method takes the row and the column vector of the reconstructed matrix as the training vector sequentially to extract independent components. Since the dimensionality of the training vector in Block-ICA is much smaller than that in the traditional ICA, it can reduce the face recognition error caused by the dilemma in traditional ICA, i.e. the number of available training samples are great less than thoes of the training vector, and thus reduce the recognition time. Experiments on the Yale and AR databases validate the effectiveness of the proposed method.关键词：block;independent component analysis (ICA);feature extraction;face recognition3637|304|0更新时间：2024-05-07
- 摘要：In view of the shortage of regional division of the commonly used gray level-average gray level two-dimensional histogram, which some object and background inner points are wrongly divided as edge and noise points, an improved Otsu threshold selection method based on gray level-gradient two-dimensional histogram is proposed in this paper. The chaotic particle swarm algorithm is used to search for the best threshold. The repeat computations of the fitness function in iteration are reduced significantly using recursion. Compared with fast image segmentation algorithm based on gray level-average gray level 2-D Otsu method and particle swarm optimization , the experimental results show that the algorithm proposed in this paper not only considers all the object and background inner points and achieves a good segmentation quality in uniform regions, accurate borders and clear details of features,but also the running time is reduced to only 1/3 of that of the existing algorithm. At the same time the convergence property of particle swarm algorithm is further improved.关键词：image segmentation;threshold selection;two-dimensional histogram;Otsu thresholding;chaotic particle swarm;recursion3772|234|0更新时间：2024-05-07
- 摘要：This paper presents a constrained energy minimization method of sub-pixel target detection for hyper-spectral imageries based on minimum noise fraction (MNF-CEM). In this method, minimum noise fraction (MNF) reduces the dimension of the hyper-spectral imageries and separates the noise from the hyper-spectral imageries. Then constrained energy minimization method (CEM) is used to detect the sub-pixel targets in the imageries of low dimension to void the computations of ill-conditional matrix inverse and virtual dimension of the hyper-spectral imageries. Experiments show that this method can restrain the influence of noise and is an effective method of sub-pixel target detection for hyper-spectral imageries.关键词：target detection;hyper-spectral imagery;constrained energy minimization.4195|259|0更新时间：2024-05-07
- 摘要：In clinical heart disease diagnosis by real-time 3D echocardiography, it is time-consuming and tedious for doctors to manually search the best views to detect the complex cardiac anatomy, when they routinely check a large amount of patients 3D echocardiographic images. Since the apical four-chamber（a4c) view is one of the most important screening planes, the purpose of this study is to detect the a4c plane in the 3D echocardiographic image automatically. Firstly, a typical a4c image is chosen as a template image. Then to find the a4c image in a 3D echocardiographic volume data, a series of cross-sections are extracted from this data to build an ultrasound image database. Via a coarse to fine retrieval, the cross-section in the database most similar to the template is taken as the a4c image in this 3D data. Tested on 28 datasets of normal children and 22 datasets of children suffering from congenital heart disease, this method achieved the accuracy rates of 96% and 86.3%, respectively. By only one template image, this method can detect the a4c image planes in the echocardiographic volumetric datasets of different subjects. With low computational complexity and simple implementation, the proposed method gives promising results for applying the auto-detection of the a4c view to clinical diagnosis, which is significant for following computer-aided diagnosis approach such as registration and measurement.关键词：real-time three-dimensional echocardiography;template matching;image retrieval3386|229|0更新时间：2024-05-07
- 摘要：According to the pathological characteristics of skin hypertrophic scar tissue, texture features on the edge direction, density distribution and geometric morphology are extracted from two-photon excited microscopic images of scar tissue and used to distinguish the normal tissue from scar tissue. Algorithms of mean-shift are applied to analyze the extracted texture features. Finally, a compositive formula is presented for quantitatively analyzing images. 118 two-photon excited microscopic images originated from human hypertrophic scar tissue are statistically analyzed based on this formula and the inaccuracy rate is 5.1%. These results indicate that texture features and analytic methods proposed in this paper are effective on distinguishing the normal tissue from scar tissue and accurately fixing on their border.关键词：hypertrophic scar;two-photon excited microscopic image;collagen fiber;elastic fiber;texture analysis3420|233|0更新时间：2024-05-07
- 摘要：An occluded human segmentation method in infrared image was presented in this paper. Firstly, the occluded regions binary mask was obtained using traditional infrared image segmentation methods such as threshold selection or histogram clustering. Then, two mean shift clustering process were carried out separately using the objects relative row and column coordinates to the mask as feature sets. Each pixels convergence position in vertical and horizontal direction was represented by a complex vector. Finally, another mean shift process was carried out on all the complex vectors, and the object masks pixels were classified according to their corresponding complex vectors cluster. Thus, the objects were segmented in the binary mask. Compared with the watershed algorithm, the segmented results of our algorithm were complete and could be controlled from coarse to fine by changing the mean shift bandwidth parameters.关键词：infrared image;occluded human segmentation;mean shift;watershed algorithm3941|254|0更新时间：2024-05-07
- 摘要：Objective evaluation of medical image segmentation algorithms is one of the important steps toward establishing validity and clinical applicability of an algorithm. Since there are a large number of articles presenting segmentation methods on medical image, with few studying the evaluation methods on their performance, this paper presents an evaluation method for different segmentation algorithms. The author first gives a survey of several available evaluation methods and presents a systematic summary. Reliability, precision, region statistical characteristics and efficiency are the four most important metrics. The definitions of them are then described based on the image segmentation process. For comparison, weights should be added to these metrics according to the application. Moreover, the author also presents a method on how to construct gold standard of medical images. At last, with the task of brain white matter segmentation, the author demonstrates how to make use of the proposed evaluation method to compare two segmentation algorithms in insight toolkit（ITK). The experiment results show that this method is practical and reasonable. This study gives a scientific method for the evaluation of segmentation algorithms on medical image. Meanwhile, it points out the problems to be solved before the segmentation algorithms could be put into use in clinic.关键词：image segmentation;segmentation evaluation;medical image;insight toolkit(ITK);gold standard6383|325|0更新时间：2024-05-07
- 摘要：In order to improve the current image retrieval methods based on color and texture which are deficient in describing the spatial relations, in this paper, a new method called features integrated matching for region based image retrieval（FIM-RBIR) is proposed. At first, the image is segmented using a coarser resolution scheme, then the color and texture features of sub-regions are combined to achieve the image retrieval. The experimental results show that the FIM-RBIR algorithm is more accurate than the SIMPLIcity method, the average retrieval performance has been raised by 4.33%, better average precision ratio and robustness has been obtained.关键词：content-based image retrieval;MPEG-7;region-based segmentation;color;texture3531|251|0更新时间：2024-05-07
- 摘要：The active shape model is one of the important method in the field of the deformable models. In the fields of the medical image analysis and machine vision, it is an ever-increasingly broad application method. During the process of image fitting, however, distortions and displacements often happen if the target is not clear or the initial position of the model is not ideal, and there is a lack of effective correction strategies. In this paper, we firstly propose an active detection and correction based on the boundary moment invariants. By introducing the boundary moment invariants, the changes of the model can be quantification, and can be detected and corrected according to the statistical information which is obtained from the training set. Using the proposed method, distortions are effectively avoided and the accuracy of fitting result is obviously increased with little extra time. Finally, the results of our practical implementation prove that the proposed strategy works satisfactorily.关键词：active shape models;shape distortion;boundary moment invariants3112|297|0更新时间：2024-05-07
- 摘要：Vision system calibration is the first and foremost task in ping-pong robot. To reduce the deficiency of the traditional binocular vision cameras method in heavy computation and difficulty in image synchronization, a new calibration algorithm is proposed to deal with a monocular vision system. Based on the monocular camera model，the stereo mapping is transferred to the planar mapping. Using the projection geometry relationship between light, ball and shadow, both the least square method and the optimized error estimation method are used to evaluate the parameters of the vision system. Furthermore, it lays a foundation of 3D position calculation and trace prediction. This method has been proved to have high accuracy to locate the object in the scene (<4 mm) and high-speed image processing (>60 fps). It is an effective and reliable way in computer vision compared with binocular stereo vision in structure size, measurement speed, and cost. Also it has a wide application prospect.关键词：monocular camera;ping-pong robot;calibration;shadow3391|219|0更新时间：2024-05-07
- 摘要：Aiming at improving the limitation of adjustment and interaction by using the traditional geometric modeling methods, this paper addressed the physically-based method and FDM（force density method) for surface modeling. By building the linear constrained functions of minimal external forces and the changes of free nodes, our system thus adaptively drove B-spline surface deformation. We proposed the genetic solution to kinds of geometric constraints. Moreover, we put forward the intuitive approach to local and global deformation by interactively sketching targets and limiting curves. A series of experiments finally proved the efficiency of this method.关键词：force density method;geometric constraints;interactive surface deformation;B-spline surface3523|233|0更新时间：2024-05-07
- 摘要：Image Warping includes the forward and backward methods respectively according to the mapping directions. However, out-mapping and holes often exist in the forward approaches, while backward ones cost much computing resources. A novel bidirectional zooming image warping method is proposed in this paper. Instead of the traditional unidirectional mapping, a backward mapping and subsequently a forward mapping are performed to achieve the warping. The new method gives a good solution to current problems by only adjusting the direction of mapping and the order of drawing, without any extra preprocessing and limitation of scene. The promising results can be obtained from both theoretical and experimental studies.关键词：Image Warping;bidirectional;zooming4603|263|0更新时间：2024-05-07
- 摘要：A novel arrangement method of virtual-combined pixels is proposed for a dynamic image display effect. On the basis of traditional pixel arrangement, it adopts the control technique of pixel multiplexing, adjoining permutation, combination and virtual processing. The dynamic display with 1×M×N physical pixels will be the same demonstration effect as the dynamic display with 8×M×N physical pixels. A data algorithm and its logical structure are also presented. After processed by the algorithm, the original image data acquired by the computer can obtain the combination value of corresponding image pixels. Experiment shows that the data extraction and processing are real-time. Moreover the image bandwidth is reduced by 2/3 and the image demonstration effect is enhanced almost 8 times.关键词：dynamic information display;LED board;virtual- combined;data integration algorithm3713|266|0更新时间：2024-05-07
- 摘要：It is one of the most important parts of the research on virtual battlefield for 3D military symbol modeling. A dynamic modeling method based on the control grid was declared, Bezier grid and DEM grid are used to control the military symbol models 3D shape. The military symbol is divided into several line segments according to its slope. Then, a Bezier grid is drawn around the symbol, when the Bezier grid is warped. The symbol will be projected into the grid, as well as the line segments are transformed into 3D space and are optimized by the angle of two line segments. With surface reconstruction from Delaunay triangulation, a 3D military symbol will be created. The DEM grid is used to control the 3D military symbol models shape also; the 3D military symbol can be limited into the DEM grid and follow the DEM grids surface.关键词：3D military symbol;modeling;Bezier grid;DEM grid3885|238|0更新时间：2024-05-07
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