最新刊期
卷 6 ， 期 5 ， 2001
- 摘要：This is the sixth in the survey series of yearly bibliographies on image engineering in China. Considering the current status of the researches on image engineering and the applications of image techniques as well as the distribution of related publications in China, more than 400 research and technique references are carefully selected by counting on their topics from more than 2100 research papers published in a set of 15 Chinese journals. These 15 journals are considered as important journals in which papers concerning image engineering are relatively concentrated. These references are classified into different categories according to their contents. Some analysis and discussions of the statistics made on the classification results are also presented. At this great milestone that we step into the new millennium, some new classes related to emerging research hot points are added. This work shows a general and up to date picture of the progresses of image engineering in China. It also supplies a convenient means of literature searching for readers doing researches and/or applications in this field, and provides a useful reference for the editors of journals and potential authors of papers.3294|436|0更新时间：2024-05-07
- 摘要：This paper shows one of the demonstrating results of remote sensing information processing researches in China Remote Sensing Satellite Ground Station, CAS. Based on the analysis of the relationship between the building heights and the shadows in panchromatic SPOT image, the paper presents the principle and the method for building heights estimation in a city from the shadows of an image. And works out a feasible approach for determining shadow zones in a panchromatic SPOT image. It has also contributed an automatic technique for extracting buildings' distribution information of different heights in a city from the shadows in a panchromatic SPOT image. Different from the previous studies mentioned in published articles, of which they focused on height setimation of single object or several buildings. The most important challenge of this paper is how to extract buildings' distribution information of different heights in a city from the shasows in a panchromatic SPOT image automatically. Although the basci law for height calculating addressed in this paper is similar to what the used.A result with above 80% accuracy has been achieved while applying this technique to Beijing City, which has demonstrated prospecting applications of satellite remote sensing for urban purposes.3071|442|0更新时间：2024-05-07
- 摘要：Pixel classification is one basic issues of image processing. A novel method of pixel classification based on orientation information measure of image is presented. Firstly, the general characterisitics of the pixels belonging to various pixel calsses are discussed, and the radical principles of pixel classification are also given in this paper. Then, each pixel of a gray value image is classified into the edge, the smooth, or the textured feature point, based on the orientation information measure of image, and variance of the orientation information measure when the scale of observation is changed. The method effectively integrates the multi scaled observations of image and the information measure of image. Finally, the effectiveness of this method has been testified by some experiments in the end of this paper. The method can generally be used as a front end of image processing and image analyses, has the better capability for denoise.2584|430|0更新时间：2024-05-07
- 摘要：This paper points out that for the embedded zerotree wavelet(EZW) image coding, the discrete wavelet transfor(DWT) must be calculated with the original coefficient of the filters,scaling the coefficient of the filters can influence the performance of the coding.The delay of the low pass filter also has important effect on the coding performance,in order to ensure the self similarity among the images of the wavelet subbands,the delay of the low pass filter must be zero.By using the character of biorthogonal wavelets,which have dyadic rational filter coefficients,this paper presents a fast multiplierless DWT algorithm,which is very suitable for EZW image coding.The multiplierless DWT can be performed with only bit shift and integer addition operations,and moreover,the result of the multiplierless DWT is equivalent to the original DWT which is calculated with the original coefficient of the filters.At last,combining with the fast EZW algorithms,a fast and high performance image coding system is presented.2885|523|0更新时间：2024-05-07
- 摘要：Forgery prevention and detection are of great social importance.This paper attempts to apply digital watermarking into forgery prevention. The digital watermarks are embedded into the most important DCT coefficients except the DC coefficient of the original image through linearly additive operation.The corresponding watermarks are extracted throught threshold judgement and the threshold is determined through the difference of two cycle print&scan and one cycle print&scan of the images.To improve the robustness of the algorithm,the simple and effective repetition is applied to watermark configuration.And the CIELab color space is chosen to guarantee the repetition of the results and minimize the error brought by the transference of images between differnt equipments.Experimental results show that the proposed algorithm can satisfy the requirements of forgery prevention for ordinary images,that is to say the digital watermark is robust to one cycle print&scan and fragile to two cycle print&scan. Compared with other forgery prevention and detection techniques,the algorithm described in this paper reduced the computation cost considerably as no other special material or equipment is required and ordinary user can verify the authentication of printing materials. This algorithm can also be used in printing materials copyright protection,such as the owner verification in certificates,passports,ect.2824|483|0更新时间：2024-05-07
- 摘要：Image segment plays an important role in the field of image processing, and currently the hybrid approach combining the manual and automatic methods is widely used in segment practice. In this paper we present an algorithm capable of locating the target object contour of sharp tips accurately in the interactive rate. Considering that the edge are usually on the zero-crossing points after Marr transformation for most images, existing techniques tend to give undesirable results because the energy path containing more points is given less priority. In our method we specify a pointer to point the current point on a path of interest, when the energy of current path is less than the energy for the previous point, we checknlatest points in the current path instead of checking only one point as existing techniques do, and, if more thanmpoint (m n) is zero-crossing, the pointer of the point is updated, otherwise, the pointer remains unchanged. Using this criterion we can insert new seeds automatically near the tips of the target object and the burr is eliminated by a vectorization approach. The final contour traced out fits the feature of the target object well and the effectiveness of our method is demonstrated by examples shown in the paper.2699|442|0更新时间：2024-05-07
- 摘要：This paper presents an automatic system for human face and moving object recognition. The system developed is based on a novel recurrent stochastic neural network, it has a strong learning power and is able to recognize a moving target in real time. The detection of the moving object is implemented by utilizing the skin color distribution and the motion information. The object is tracked in real time with an efficient adaptive mean shift algorithm. The work in this paper is mainly focused on the disign of the novel recurrent neural network and the efficient incremental Boltzmann learning algorithm. The improved simulated annealing technique is also discussed. Theoretical results offer a unique solution to the training of a large size network. Experiments on human face recognition are carried out with a recurrent neural network of 4827 neurons and 129951 connections. The results show the performance of the recognizer is comparable to that of the well known TrueFace system.2702|502|0更新时间：2024-05-07
- 摘要：Hilbert spatial ordering based on Hilbert Peano curves is an excellent linear mapping method, and gets wide applications in spatial querying and spatial indexing. The traditional algorithm for Hilbert ordering code is based on binary bit manipulation on Morton code. It has a complexity of O(n 2 ). In this paper, the author set forward a new generating algorithm for Hilbert ordering code, which is implemented by raster space recursive decomposition and regional phase shifting vector, and has a complexity as O(n) .Experiments have valideted the efficiency of the new algorithm. The algorithm has been applied in a feature based non planar data model for urban traffic networks to generate the address code so as to facilitate the point feature dynamic indexing based on balanced binary ordering tree and the linear feature indexing based on vertex retrospection. The address codes for querying area boundary cells can be used to separate the area into several sub areas to decrease excessive searching. Spatial ordering based on Hilbert code facilitates spatial clustering of the spatial objects and speeds up data extraction. Spatial indexing with Hilbert code is more efficient than sequential indexing when a great number of spatial objects are procesed. It is distinct for spatial extent and proximity querying.3186|478|0更新时间：2024-05-07
- 摘要：Vector field visualization is one of the most challenging research issues for Visualization in Scientific Computing, which enable an efficient insight into the physical essence behind large|scale but abstract data obtained from scientific computation and experimentation, and has been paid more and more attentions, and widely used for those areas such as Computational Fluid Dynamics, aerodynamics, atmospherical physics and meteorology analysis. This paper extended LIC to VolumeLIC for 3D vector field visualization by volume rendering 3DLICed volumetric texture. Sparse Line Noise was designed and combined with Ramp Convolution Kernel to improve VolumeLIC image, with direction and depth cueing enhanced. HRCK was presented to create smooth cyclic animation without any pulsation. VolumeLIC Probe was further proposed for interactive insight deep into 3D vector fields.Finally, Closely based on above research work, VF|VTK(Vector Field Visualization Tool Kit) was exclusively designed and developed for three practical applications, the Visualization of the mantle movement, the flow field,and the high altitude airflow field. These applications have indicated that the methods presented in this paper are convenience, efficiency and robustness in practice.2822|418|0更新时间：2024-05-07
- 摘要：This paper puts forward the definition of phase density to quantificationally describe how the attractor distributes in the phase space, which provides effective foundation and control for strange attractor visualization. The phase density can be calculated as the proportion of the number of phase points fallen into the vessel box which is positioned around each phase space point, thus clearly denote the denseness of attractor distribution around that point. Based on the phase density, the volume rendering and Lyapunov spectra rendering of strange attractor visualization can unveil the total chaotic behavior and local attributes of strange attractor respectively. During the attractor volume visualization, the source instension and the attenuation coefficient are both defined as nonlinear component according to the average phase density, and the image ordered algorithm is adopted to reduce the expensive computation. During the Lyapunov spectra visualization, the initial iterative point pair is first picked up automatically according to the phase density, and the adaptive growing up algorithm of flow pipe (or flow ribbon) can be implemented recursively from each initial point pair. The given typical strange attractor visualization examples demonstrate that the content and form of strange attractor visualization are enriched with the complexity is depressed.2532|420|0更新时间：2024-05-07
- 摘要：Firstly, this paper studies road information requirement of ITS oriented digital maps. Single lined road network model based on road node connection is presented. Conventional network based on road segment connection has some difficulties to represent real world road networks, however model presented in this paper works well and can be easily operated. Then, this paper mainly focuses the research of the study of automatic generation algorithm of road network databased of aforementioned model when digital maps is been making. Road segment breaking preprocess is adopted to break all road segment vectors from intersection points. Road nodes and segments information lists are created then, and through modifying the two lists, road network is traversed. Road segments and nodes are coded automatically when traversing, and at the same time topographical information is gotten. After this process, road network database can be constructed with road nodes and segments associating with each other. In the end, special cases of preprocess is discussed on intersection points getting. Experiences show that the model and algorithms presented in this paper are reasonable and feasible.4406|629|0更新时间：2024-05-07
- 摘要：Implicit surfaces can be used to generate complex topology objects and offer special effects for animators and graphic designers, and they are finding extensive use in a growing number of graphics applications. In contrast to traditional parametric surfaces, implicit surfaces can describe smooth and topology evolving shapes conveniently. Distance surfaces are defined by distance to skeletal elements such as points, curves, surfaces and volumes. In this paper we propose a new fast distance surface computation approach based on optimized arc spline approximation for 2D curve skeletons. For an arbitrary 2D NURBS curve, we first fit it using fewest arc splines within the specified tolerance, and the nearest point to the curve problem is then transferred into the nearest point to an arc spline curve. As a huge times of nearest point computation are involved in the polygonization of distance surfaces, our algorithm is very efficient as the nearest distance from a point to an arc spline curve can be obtained analytically within little computation. Experiments show our algorithm is both simple and useful, and it is of high potential value in practice.2674|512|0更新时间：2024-05-07
- 摘要：This paper expounds the definition of the general Julia sets (they are called the general J sets for short) from the complex mappingz←zα+c(α<0). A series of interesting and rich families of fractal images are generated by changing a single parameterα. Whenαis a negative integer the fractal image has a planetary configuration consisting of a central planet with α major satellite structures. For noninteger values ofα, additional embryonic satellite structures, proportional in size to the fractional part ofα, are observed. Using the experimental mathematics method combining the theory of analytic function of one complex variable with computer aided drawing, we have analyzed the structural characteristics and the evolutions of the general J set for negative real index number. That the different evolution of the general J set results from the different choice of principal range for the phase angleθis found, and the four evolutions of the general J set are given for the first time.2583|405|0更新时间：2024-05-07
- 摘要：This paper discusses the structure of decision model in intelligent virtual environment. Intelligent virtual environment is dynamic environment, that is to say it keepes on changing, decision in intelligent virtual environment also should be dynamic, it must be rapid enough to react to the change of environment. To meet the real time and dynamic requirement of decision in intelligent virtual environment, this paper improve the traditional planning method. The time critical A * algorithm is used to implement real time planning, current action is generated only in a predetermined decision time slice, which is different to traditional planing method. action stack is also employed to store the selected action, which is convenient to evaluate the action in time according to the situation of environment, so, we can discard those unreachable targets in time. Based on that, this paper developes a decision agent to instruct the virtual human in intelligent virtual environment. In addition, a small intelligent virtual environment is developed to test the decision model. At last, Influence of length of decision time slice is test, it shows that the suitable length of decision time slice is about 0 3 seconds.2571|401|0更新时间：2024-05-07
- 摘要：IP based video communication is becoming increasingly important in recent years. One inherent problem of IP based video communication is channel errors. Current video compression standards achieve efficient compression by using predictive coding and variable length entropy coding. Variable length coding techniques are highly vulnerable to channel errors. The channel errors cause the decoder to lost synchronization with the decoder. Predictive coding techniques make the errors quickly propagate across the entire video sequence. So the effect of these errors not only can cause great degradation of the quality of reconstructed images, even can lead to the failure of the whole video communication system. Error resilience techniques have been employed to reduce the effect of the channel errors. The syntax and the structure of compressed video stream have been modified to get error resilient video stream. So the decoder can much more easily detect errors and to recover the lost data from the errors. Error resilience techniques also use the spatial and the temporal correlations within the video sequence to reduce the degradation of the quality of reconstructed images.This article presents an integrated resolving scheme of error resilience technologies for IP based video delivery. This scheme employs severel error resilience technologies, such as the slice mode, resynchronization and error concealment, etc, it can greatly increase the error resilient capability of the video codec. We also implement error resilient H 263 and H 26L codec based on this scheme. This article also gives some simulation results of error resilience technologies based on Internet models. The result shows error resilience technologies can remarkably improve the subjective and objective quality of the reconstructed image.2784|482|0更新时间：2024-05-07
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