最新刊期
卷 10 ， 期 7 ， 2005
- 摘要：As one of a serial of reports,this paper is a survey on multimedia researches and applications in China in the year 2004.Since multimedia is a cross research area,papers about multimedia technology are distributed on various journals.We checked about(2 926) papers published on 9 Chinese journals in 2004,from which we have selected 363 papers related to multimedia technology and application.Then we analyzed them and the statistics were compared with those from 2000 to 2003.Looking into the data we can find that researchers in China are continuously paying much attention to digital watermarking,virtual reality,multimodal interface,multimedia information retrieval technology,quality of service,computer supported cooperative work,GIS and Digital Earth as these fields have shown increasing research internationally.We present here an overview on the progress in multimedia technology in China,2004.This article will make convenience for researchers to find references,and be helpful for editors to edit journals and for authors contributing papers.关键词：multimedia;virtual reality;hypermedia;multimedia communication;CSCW;multimodal interface;wireless multimedia2654|204|0更新时间：2024-05-08
- 摘要：In order to realize edge detection adaptively and effectively,this paper presents an edge detection algorithm based on odd Gabor filter and Rayleigh distribution.To obtain the edge response,an improved odd Gabor filter based edge response obtaining method was proposed,which increases the computational efficiency and avoids the estimation of gradient direction.For the differential property of odd Gabor filter,the edge response based on odd Gabor filter was fitted by a Rayleigh distribution.To overcome the shortcomings of existing threshold selection approaches,a Rayleigh distribution based nonlinear adaptive threshold determining method was given.Both the synthetic and natural images were tested in our case.The experimental results show that the proposed edge detection method has good detection property and adaptability.关键词：edge detection;Gabor filter;Rayleigh distribution;adaptive threshold2919|201|0更新时间：2024-05-08
- 摘要：ion It is meaningful to abstract edge feature point from a large amount of 3D point cloud in the reconstruction of curved surface.The 3D data we get must be processed firstly in order to avoid the distortion and deviation during the course of reconstruction.But the common methods for this problem are of little use because noise points and the feature edge have not been analyzed and distinguished.According to this,a new approach based on wavelet edge detection is presented.We select a kind of wavelet similar to mexh as a tool exclusively to detect these two kinds of edge feature points,The following experiments show that: the edge feature points are located accurately by ignoring the disturbance of noise and redundancy.Comparing with former data proceeding methods,this method is more accurate and overcomes the influence of noise simultaneously.关键词：mexh wavelet;3D point cloud;edge feature point2847|195|0更新时间：2024-05-08
- 摘要：An improved image filtering on Rough Sets is proposed in the paper.The method regards the traditional selective masking smooth filtering method as the thinking foundation.According to looking for the mask a pixel belongs to,then the mask RS precision approximation is used to precede image pixel to smooth whole image.It not only realizes cleaning noise and keeping the boundary, but also increases the contrast of picture and makes vision distinction restored picture to original one be minimum.In another words,while denoising the method keeps good details,increases the contrast degree of the picture,and improves the picture quality than the traditional pre-processing method.关键词：rough sets;image smoothing;noise filtering;selective masking2474|180|0更新时间：2024-05-08
- 摘要：Mumford-Shah model,which has better ability to segment images, had been used to segmenting images or tracking targets.But it needs computing all the data of the image constantly during the iterative course,so it is not suitable for real-time application for its low efficiency.Aiming at this disability,by using the characteristic of the MRI,a fast method of solving the M-S model is improved based on the histogram method.This method first construct a signed table,which can be used to distinguish the area inside or outside of the edges,and use the histogram method to get the rough results,then use the searching method to optimize the results and get the final edges.Experimental results show that the new model can get the better results in an efficient way.关键词：M-S model;C-V model;histogram;region information;MRI segmentation2352|188|0更新时间：2024-05-08
- 摘要：To eliminate the effects of the changes of lightings,the conventional approaches firstly produce a compensation based face image under standard illumination from the input image,and then match it with the face templates in a database.In this paper,a novel face recognition approach for different illumination conditions is proposed.The proposed method generates a new gallery under the same lighting conditions with an input image instead of transforming the input image.First,a face illumination eigenspace is constructed from nine face images of the same person taken from nine basic directions respectively.And then,the face images in the face image database are transformed into the rendered images taken under the same illumination with the input image based on the face illumination eigenspace.Finally,the input image is matched with the newly rendered images which are regarded as a new gallery,to perform the recognition task.The experimental results show that the proposed approach can efficiently eliminate the effects of different illuminations,and has a high recognition rate in the illumination conditions with remarkable changes.关键词：face recognition;illumination eigenspace;eigenface3641|185|0更新时间：2024-05-08
- 摘要：Volume rendering is often used for 3D volumetric datasets visualization.It can generate high quality images,but can not render volumes and polygons combined scenes.Among many currently available techniques of visualizing hybrid scenes,some can render volumes and triangles combined scenes,but can not process geometric points and lines.To correctly render these complicated hybrid scenes,a ray casting based algorithm using SIMD and software acceleration techniques is presented.The algorithm has three types of rendering order,each of which has its own advantages and drawbacks for different applications.It can be adopted in parallel and perspective projection for many applications.Experiments show that the algorithm can properly visualize volumes,polygons,lines and points combined scenes,and rendered images have high quality and its rendering speed is very fast.关键词：3D visualization;volume rendering;ray casting;computer graphics & image processing2750|208|0更新时间：2024-05-08
- 摘要：Image interpolation is a basic problem of image processing,in order to get a more reasonable weight function,the paper studies the application of gradients in one-dimensional signal interpolation,and generalizes it to the interpolation of image,then obtains a method for image interpolation based on gradients.In linear interpolation model,the weighted function is only dependent on the distance of the pixels,but not on the gradient,which often leads to the blurring of the image.Since image is a piecewise continual function,the gray value of an unknown pixel is closer to the pixel with smaller gradient than the pixel with bigger gradient,so a decreased weighted function of gradient is constructed in this method to interpolate the unknown pixels.It also discusses the selection of the related parameter in the model,and obtains a reasonable parameter based on the distribution of the gradient.The algorithm is tested on two images,all results show that the new method has higher peak signal to noise ratio and better intensity of image than known methods,and that it suits to simple image especially.关键词：image interpolation;gradient;weight function3769|230|0更新时间：2024-05-08
- 摘要：Based on the half-baked skull of the victim,it is most important for criminal reconnaissance to reconstruct the victim's 3D appearance.In order to reconstruct 3D appearance truly,a new method of calculating parenchyma thickness is put forward in this paper.It is mainly based on convhull method with spire CT.We can establish a statistical neutral parenchyma thickness database by nation,age phase and so on.At last,we bring forward a proposal of the 3D facial reconstruction relying on subarea and convhull.Testing by the correlative department and the analysis of the reconstructing effect,it is proved to be effective and feasible,and we have acquired the anticipative effect.This method is more objective and faster than the other existing methods.2746|177|0更新时间：2024-05-08
- 摘要：This paper addresses the problem of image compression in remote sensing applications.Compared with other still images,remote-sensing images are characterized with complex textures and weak local correlation.By using wavelet transform,the coefficients have shown a spatial clustering trend in wavelet domain.Most of current algorithms of image compression have not taken this clustering trend into account.In order to further improve coding efficiency,an efficient remote sensing image coding algorithm based on morphological wavelet is proposed.First the fast multi-scale wavelet transform is applied to the image, then a morphological operator is designed to capture the clusters and fully exploit the redundancy between the coefficients.Compression is then achieved by using this non-linear method.For multi-bands remote-sensing images,a prior important band(PIB) method is firstly used to decorrelate the correlations in the spectral dimension,and the above coding algorithm is then applied to the bands.In the experiment,the authors select one AVARIS hyper-spectral image and two satellite images to test the performance of the algorithm.Experimental results illustrate that its performance is superior to JPEG2000 in low-bits compression and it is suitable to multi-band images too.关键词：remote sensing image compression;morphological wavelet;spatial clustering;morphological operator2657|176|0更新时间：2024-05-08
- 摘要：By studying the spatio-temporal correlation and the center-biased characeristic of motion vectors in image sequences,this paper classifies the macro-blocks as different types and takes advantage of the relative blocks instead of neighbour blocks to predict the initial point.A new adaptive motion estimation algorithm based on selecting predictive initial search point is presented,according to which different modes are agilely selected in accordance with image contents.It has been proved with the experiments that this algorithm greatly improves the searching speed and at the same time guarantees image performances with consideration to complexity and accuracy of motion estimation.关键词：motion estimation;motion vector;spatio-temporal correlation;initial search point prediction2436|197|0更新时间：2024-05-08
- 摘要：Based on evolution strategies(ESs) a novel adaptive motion estimation search algorithm is presented in order to improve the encoder quality.The mutation operator in ESs is used with frequency corresponding to the normal distribution law.This algorithm applies the ES algorithm to block motion estimation,the motion direction factor participates in motion vector computing as a variable for the first time,and affects the whole search process,neither just being an implicit factor nor a predictive measure.The adaptive schemes are advanced in the step length control and population sizing.Experimental results demonstrate that this algorithm has similar performance to that of the full search algorithm,and owing to its inherent parallelism and low complexity it is suitable for VLSI implementation.关键词：motion estimation;correlated mutation;evolution strategies;1/5 success rule2099|164|0更新时间：2024-05-08
- 摘要：Half-pixel motion search is growing in importance for the whole coding process due to the adoption of fast integer pixel search algorithms.A minimal matching error direction prediction-based fast half-pixel motion vector search algorithm is proposed in this paper to reduce computation load of half-pixel search.Based on the single peak characteristic of half-pixel error matching function inside search area,the minimum matching distortion direction is predicted and possible half-pixel candidate positions with minimum matching distortion are selected based on SAD values comparison results of four integer-pixel points around integer-pixel motion vector.The experimental results reveal that,to all kinds of video sequences,the proposed algorithm can obtain almost the same video quality as that of the half-pixel full search algorithm while reducing at least 66% computation cost.关键词：video compression;video coding;motion estimation;block matching;half-pixel search2719|182|0更新时间：2024-05-08
-
- 摘要：An digital image watermark algorithm is proposed based on the synergetic neural network,combined with encryption technique,to guarantee its robustness and security.The meaningful gray image is serially processed into watermark signal and embedded into the DC elements of the block DCT coefficient matrix of the host image.Watermark detection/extraction algorithm is realized by using synergetic neural network.The(network's) input is possible watermark signal and its output is the recognition result.The emulational experiments indicates that,the proposed algorithm can fulfill the watermark detection/extraction at one time after image processing,and identify the watermark owner which shows good performance.关键词：digital watermark;synergetics;neural network;digital image process2594|189|0更新时间：2024-05-08
- 关键词：curve surface;triangle mesh model;shortest path2781|188|0更新时间：2024-05-08
-
- 摘要：In this paper,a new method of image fusion method was proposed based on principal component analysis(PCA) and wavelet transforms(WT) to fuse a low-resolution multi-spectral image and high-resolution panchromatic image.Firstly,the multi-spectral image is transformed with PCA.Then,the first principal component of multi-spectral image and high-resolution panchromatic image were transformed by WT,respectively.The high-resolution panchromatic image approximation can be merged into the multi-spectral image approximation using antitheses of imaging intensity by means of multi-resolution wavelet decomposition,and then the merged image is reconstructed by inverse wavelet transform and replaces the first principal component of multi-spectral image.Finally,the fusion image is obtained by taking the inverse PCA transform.The experiment indicates that the performance of new method is better than those of IHS transform-based fusion method,PCA transform-based one,and WT transform-based one.It not only preserves spectral information of the original multi-spectral image well,but also enhances spatial detail information.关键词：image fusions;wavelet transform;principal component analysis transform;IHS transform3138|213|0更新时间：2024-05-08
- 摘要：Traditional hard classification of remote sensing images has been proved to be inaccurate due to the presence of mixed pixels in images.Even though the composition of these pixels for different classes can be estimated with pixel unmixing model the output provides no indication of how such classes are distributed spatially within these pixels.Sub-pixel mapping is a technique designed to obtain the spatial distribution of these classes in these pixels with information contained in mixed pixels.A newly Cellular Automata model was proposed to solve the problem of sub-pixel mapping with the assumption of spatial dependence.The model was tested on both synthetic and real images,and the result shows that this Cellular Automata model is a simple and efficient method to solve the sub-pixel mapping problem.关键词：remote sensing;classification;mixed pixel;sub-pixel mapping;cellular automata2813|207|0更新时间：2024-05-08
- 摘要：The basic idea behind a multi-scale representation is to embed the original image into such a one-parameter family of derived images,which become more and more smooth and simple.The simplification means the loss of details and information.It is important to measure the information of an image at a given scale and the loss between scales.Based on the vision theory and intuition of image processing,the paper proposed seven principles: nonnegativity,causality,Geometric invariability and so on.Sporring and Weickert have proposed a method of information measures.But Sporring's measure can not satisfy the principles proposed in this paper.This paper presented a new information measure based on the Marr's Vision Theory.In Gaussian Scale space of one dimension,we used the number of the first-class and the second-class of points as the information measure.Use the theory of Gaussian scale space,this paper has proofed that the new measure method satisfies the principles proposed.Then we extend the method in two dimensions directly.Experimental results proof its reliability.So this is a good choice of information meausures of scale-space based on the visual characters.关键词：scale space;Gaussian scale space;information measures;scale selection2894|166|0更新时间：2024-05-08
- Postal code：100190
- Tel：010-58887035/58887030/58887418 Email：jig@aircas.ac.cn
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备05080539号-4
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0