最新刊期
卷 10 ， 期 3 ， 2005
- 摘要：Because of having processing error and assembling error the difference exists in the model of the camera optical system and pinhole model, which results to nonlinear distortion between real image and ideal image to some extent. To improve the accuracy of such quantitative analysis as image measuring and pattern matching, it must be corrected. Recently, many scholars have a lot of research on this problem. To open the present state of this field before everyone, the models about camera imaging and lens nonlinear distortion are introduced, and the correction methods of nonlinear distortion of camera lens are viewed, which are divided into the method based on controlling object and the method based on pattern. Finally, the application problems are analyzed and compared.4592|253|0更新时间：2024-05-07
- 摘要：With the development of communication and video coding technology, it is possible to transport video content via network and wireless channel at present. In these circumstances, with the existence of packet loss (network) and bit errors (wireless channel), video data is corrupted usually. To overcome this, many methods have been proposed. These methods can be classified into three main fields: source coding, channel coding and joint source and channel coding. Multiple description(MD) coding has been proved to be an effective method of source coding to overcome errors(packet loss specially) in channel transport. To make people have a concise knowledge on the multiple description coding, the main features of MD coding are presented. From the views of source coding and channel coding, the main methods used to solve the problem of packet loss are concluded respectively. Additionally, some new advances in the application and research of MD are discussed. Finally, the authors point out the of the future work.3055|201|0更新时间：2024-05-07
- 摘要：In the field of image processing, Image segmentation is the basic problem. Using mixtures of!Gauss, Some people segment image by single pixel value and get poor precision and lower efficiency. For segmenting image well, in this paper, we present a texture image segmentation algorithm by image patches. It is inspired by sub space on some authors. Our experiences show that this algorithm can segment texture image a little, although it cost very much in time. Then we take mean, stand deviation, maximum, minimum and middle pixel value of image patch as features. Our algorithm segments texture image very well. Especially, it improves a lot in time.5652|256|0更新时间：2024-05-07
- 摘要：In this paper, the application of spectrum ratio to the segmentation of cell multi spectral micrograms is discussed and a new cell segmentation method is presented which combines spectrum information of multi spectral images with traditional segmentation methods. Firstly, background is removed from the multi spectral images. Secondly, two selected bandwidth images are divided to make a new ratio grey image. Thirdly, the new grey image is segmented with automatic multi threshold methods. Finally, the segmented regions are smoothed by morphological operations and the overlays of the plasm and the nucleus are obtained. In this paper, spectrum ratio technique is firstly introduced into the segmentation of cell multi spectral micrograms. The experiments with a diagnosis system on marrow cell images prove that this approach for segmenting cell images is rather accurate, fast, and robust to noise, and this method can be extended to the segmentation of other types of multi spectral micrograms.2763|187|0更新时间：2024-05-07
- 摘要：The object segmentation of defocused images with projected illumination patterns is a primary component of 3D object recovery. A segmentation algorithm, which combines multi resolution analysis and fuzzy clustering, is proposed based on features extracted from defocused images with illumination patterns to increase the segmentation accuracy. This approach is carried out through two stages: firstly building the relational matrix of multi resolution images on their similarity measures and then implementing FCM classification at lower resolution level. The proposed technique provides a novel way of avoiding the difficulties of direct segmentation. And it increases the accuracy of object segmentation. It is shown in experiments that the proposed algorithm is of effectiveness.2844|183|0更新时间：2024-05-07
- 摘要：Presents a new real time corner detection algorithm. Corners are important information carriers in object recognition. Accurate, stable and fast detecting corners in digital image are common problems facing to corner detectors. Aiming at these problems and different from traditional corner detection algorithms, based on chain code, the algorithm constructs k(k>8) neighborhood chain codes of pixels and uses these chain codes to describe contours. Based on the differential definition of curvature, a curvature function is derived from k neighborhood chain codes. Corners are detected as those contour pixels, whose curvature the is largest in a lobe of contour curvature histogram. Convex and concave corners can be differentiated quickly by checking color attributes of pixels between corner edges. To validate the algorithm, tests comparing the new algorithm to 4 corner detection algorithms are given. The results show the new algorithm is not only accurate and stable, but also simple and fast, which make the algorithm suitable for the embedded computation environment.4852|230|0更新时间：2024-05-07
- 摘要：The Euclidean method is sensitive to variations in intensity, but not very sensitive to variations in hue and saturation whereas the vector angle method detects only chromatic differences in color edge detection. The paper presents a distance combination scheme based on HSI (hue, saturation and intensity) so as to capture more accurate edge data in RGB color field. The approach is a metric that the chromaticity difference information in the form of the vector angle is mainly used in edge detection of high intensity and color difference regions, whereas the intensity difference information in the form of Euclidean distance is mainly used in edge detection of areas of low Intensity and color difference. Experiments show that our method effectively solves the problems of unstable angle calculation for vectors with small RGB values, insensitive to intensity differences for vector angle and not very sensitive to chromatic differences for Euclidean in RGB space. Compared to the LUV based measure which has already been used successfully in the LUV space, the method avoids the complexity of the color space transformation and enhances the edge detection over the LUV based results for Visible Man dataset.3113|188|0更新时间：2024-05-07
- 摘要：This paper particularly analyzes some factors possibly disturbing iris localization in the iris image through the localizing pre processing. After establishing two dimensional projection of the edge rude field, the paper researches the relation between every dimension projecting characters and the tangled distributing traits in the edge rude field, and then acquires the possible good rude field of iris edge using the way of scout and crossing, finally calculates the exact iris boundary. After the comparing test and the analysis to the iris image database, the result shows that the robust algorithm can quickly and accurately complete iris localization and it is not sensitive to different filters worked on the pre processing of the localization.2575|198|0更新时间：2024-05-07
- 摘要：Generally, one camera is used in the autonomous navigation of agricultural wheeled mobile robot. Conventional algorithm of pose sensing, however, ignores the fact that pixels in digit image possess the different weight, and its compute time can not be optimized easily. In order to overcome these shortcomings, the perspective characteristic of the linear guiding road on the ground was analyzed carefully, then the relationship between the road coordinate in the digit image and the robot pose was established, so the relative pose could be obtained directly with the Hough transformation. Based on the prototype of agricultural wheeled mobile robot, the experimental results showed that the precision derived from this method is similar to those demonstrated by the other same type of researches.2696|236|0更新时间：2024-05-07
- 摘要：Fingerprint directional image/field is a key technique of automated fingerprint identification system (AFIS). In order to improve the accuracy of fingerprint directional image further, combining the advantage of the continuity of the point directional image with the advantage of the robustness of the block directional image to the noises in the fingerprint image, a novel concept on the continuously distributed directional image/field (CDDF) and the method to compute it in the fingerprint images are developed, which transits smoothly and exhibits not only good continuity, well gradualness and excellent robustness to the noises, but very high precision, also. Therefore, it can effectively overcome the defect of low robustness to the noises of the point directional image and the weakness of low precision of the block directional image of the fingerprint image. The experimental results prove that the continuously distributed directional image can not only filter the noises in point directional image, but also represent the basic structural feature of fingerprint more precisely. Furthermore, it can solve the key problem of the continuity, the precision and the performance of robustness of fingerprint directional fields effectively, and lays the base for high precision of fingerprint image enhancement, binarization, global feature extraction, automatic classification, template matching and image encoding in AFIS.3019|190|0更新时间：2024-05-07
- 摘要：In cardiac Magnetic Resonance Image analysis, tracking tag motion is an important step in tissue motion analysis and 3 D motion reconstruction. The paper gives a method using active contour model based on kinetic function to track the tag, and uses three kinds of elastic potential energy, new internal energy and new image energy. The paper also changes the assumption that the initial velocity is zero and takes the optical flow as the velocity, which improves the veracity of the arithmetic. The method is tested on several sequences of cardiac systole MRI. The result indicates the method is effect.2297|178|0更新时间：2024-05-07
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- 摘要：The conventional average filter and median filter have different filtering characteristics to Gauss noise and impulse noise. In fact, image usually is corrupted by Gauss noise and impulse noise simultaneously, so good filtering effect cannot be obtained if we only use average filter or median filter. In this paper, a new mixture filter method is proposed. The proposed method first classsifies the pixels into two classes, one is the pixels which are corrupted by Gauss noise and the other is the pixels corrupted by impulse noise and then average filter is used for the pixels corrupted by Gauss noise and median filter is used for the pixels corrupted by impulse noise. The simulation result verifies that the proposed method is feasible and efficient.5689|303|0更新时间：2024-05-07
- 摘要：The image intensity surface for the local neighborhood of image is well fitted by the least squares support vector machine (lssvm), and then the gray level interpolation is implemented on the fitted intensity surface. The interpolation coefficient matrix of the local neighborhood is deduced from the lssvm with the radial basis function (rbf) kernel function, as an example. A method using the interpolation evaluating merit figure, psnr, to optimize the svm parameters is proposed. With the selected parameters, the computer interpolation experiments are carried out. The experimental results demonstrate the svm based interpolation algorithm has similar performance to cubic one but providing higher efficiency.2498|185|0更新时间：2024-05-07
- 摘要：A new approach for solving the spidery mesh limits in image based virtual touring , which uses a relaxing spidery mesh with two vanishing points, is proposed in this paper. Comparing with other researches work, this approach can be applied to a wider range of images for walkthrough. We have found that it can tour into the picture which has only one vanishing point, double vanishing point, and multiple vanishing points. The test result also shows that our approach can be effectively applied to the picture which contains vanishing line. In our approach, the interactive work is very simple as the user need only to interactively choose two vanishing points, the background and front object. To avoid the texture distortion, a small block texture mapping technique is used to improve the rendering quality of scene. In the test, different kinds of images are used to show the effectiveness of our approach.3069|174|0更新时间：2024-05-07
- 摘要：The contents of image include low level visual features and high level semantic in image retrieval based on content. Generally, the former is data obtained from image analysis and the latter is describing concepts in nature language, but they are not related to each other simply. The paper presents a trial with combining the main colors of color image and color names in Chinese language in color image retrieval. A new color model and a method of calculating the similarity between two colors are proposed after a few of color models are analyzed, on which a method of extracting the main colors of an image is given. The color names are discussed and a method of retrieving color images with color names is proposed. The preliminary retrieving results obtained on trial are discussed, which shows that the method is quite helpful in color images retrieval.2653|197|0更新时间：2024-05-07
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- 摘要：In digital image watermarking and image encryption, researchers often require a pseudo random sequence which is statistically orthogonal to an image. The white noise sequences, such as m sequence, are often used in these situations. But our study shows they are not optimum on orthogonal property. To get a better orthogonality, we studied the cross correlation of unartificial images and pseudo random sequences by means of statistical mathematics method. The second order expectation of the cross correlation value was determined in both space and frequency domains. The expression suggests that sequences which are high pass in frequency domain, like Run Length Limited (RLL) sequences, have better orthogonal character with unartificial images than white noise sequences which are widely used at present. The conclusion and the validity of our mathematical model were also proved by the result of statistical experiments. In order to generate 2D RLL sequences rapidly, we developed a simple and convenient algorithm. The experiments that confirmed 2D RLL sequences have better orthogonality with natural images than m sequences.2822|181|0更新时间：2024-05-07
- 摘要：In order to identify the lake water quality accurately, this paper presents a method for remote sensed image fusion based on neural networks and evidence theory. This method firstly employs a neural network for each remote sensed image and then normalizes the output of neural networks. After that, D S evidence theory is used to fuse with results from all the neural networks, resulting in the water quality evaluation. The proposed method is applied to the water quality of Taihu lake. The developed approach to water quality identification has the two features:(1) low fault tolerance; and (2) high reliability as multi source water quality data are fused.3177|213|0更新时间：2024-05-07
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- 摘要：As an efficient and simple variable length coding technique, Huffman codes are being widely used in text, image, video compression and so on. To reduce the requirement of the memory space, simplify encoding procedure, a layer information table(LIT) of Huffman tree is discussed to describe and reconstruct Huffman tree. An approach which adopts a special operating technique for a kind of structural array is designed to get data of LIT. A canonical Huffman tree(CAHT) is presented in this paper, and the existence, determination conditions and properties of encoding and decoding for CAHT are proved. Using LIT and encoding properties of CAHT, Huffman codes can be directly found. Comparing with traditional Huffman coding technique and other improved algorithms, the best advantage of the algorithm NHTC proposed in this paper is no need to create Huffman tree, so the operating process and coding procedure are more simplified and memory space requirement is reduced significantly.关键词：canonical huffman tree;structural array;encode;serial number3737|245|0更新时间：2024-05-07
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