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傅里叶变换轮廓术测量方法的分析研究 被引量:1
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作者 方坤礼 蒋晓英 甘连香 《计量学报》 CSCD 北大核心 2013年第3期207-211,共5页
对传统傅里叶变换轮廓术(FTP)、π相移法以及灰度图法测量结果进行对比分析。结果证明,随着被测物体高度梯度的增加,基于灰度图和π相移技术的改进傅里叶变换轮廓术取得了很好效果,特别是在梯度大于3的情况下适合采用π相移法,能... 对传统傅里叶变换轮廓术(FTP)、π相移法以及灰度图法测量结果进行对比分析。结果证明,随着被测物体高度梯度的增加,基于灰度图和π相移技术的改进傅里叶变换轮廓术取得了很好效果,特别是在梯度大于3的情况下适合采用π相移法,能更有效地提高傅里叶变换轮廓术的测量精度。 展开更多
关键词 计量学 傅里叶变换轮廓术 灰度图法 π相移方法 频谱混叠
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Grayscale image encryption algorithm based on chaotic maps 被引量:1
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作者 李昌刚 韩正之 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期329-331,共3页
A new image encryption/decryption algorithm has been designed using discrete chaotic systems as aSP (Substitution and Permutation) network architecture often used in cryptosystems. It is composed of two mainmodules: s... A new image encryption/decryption algorithm has been designed using discrete chaotic systems as aSP (Substitution and Permutation) network architecture often used in cryptosystems. It is composed of two mainmodules: substitution module and permutation module. Both analyses and numerical results imply that the algo-rithm has the desirable security and efficiency. 展开更多
关键词 discrete chaotic system image encryption SP network architecture
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Improved Algorithm of Histogram Equalization and Its Actualization 被引量:2
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作者 仲伟波 赵福军 +1 位作者 李鹏 宁书年 《Journal of China University of Mining and Technology》 2003年第1期52-54,共3页
A new improved algorithm of histogram equalization was discussed and actualized by analyzing the traditional algorithm. This improved algorithm has better effect than the traditional one, especially it is used to proc... A new improved algorithm of histogram equalization was discussed and actualized by analyzing the traditional algorithm. This improved algorithm has better effect than the traditional one, especially it is used to process poor quality images. 展开更多
关键词 IMPROVE histogram equalization ALGORITHM GRAY
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A Fast Underwater Optical Image Segmentation Algorithm Based on a Histogram Weighted Fuzzy C-means Improved by PSO 被引量:4
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作者 王士龙 徐玉如 庞永杰 《Journal of Marine Science and Application》 2011年第1期70-75,共6页
The S/N of an underwater image is low and has a fuzzy edge.If using traditional methods to process it directly,the result is not satisfying.Though the traditional fuzzy C-means algorithm can sometimes divide the image... The S/N of an underwater image is low and has a fuzzy edge.If using traditional methods to process it directly,the result is not satisfying.Though the traditional fuzzy C-means algorithm can sometimes divide the image into object and background,its time-consuming computation is often an obstacle.The mission of the vision system of an autonomous underwater vehicle (AUV) is to rapidly and exactly deal with the information about the object in a complex environment for the AUV to use the obtained result to execute the next task.So,by using the statistical characteristics of the gray image histogram,a fast and effective fuzzy C-means underwater image segmentation algorithm was presented.With the weighted histogram modifying the fuzzy membership,the above algorithm can not only cut down on a large amount of data processing and storage during the computation process compared with the traditional algorithm,so as to speed up the efficiency of the segmentation,but also improve the quality of underwater image segmentation.Finally,particle swarm optimization (PSO) described by the sine function was introduced to the algorithm mentioned above.It made up for the shortcomings that the FCM algorithm can not get the global optimal solution.Thus,on the one hand,it considers the global impact and achieves the local optimal solution,and on the other hand,further greatly increases the computing speed.Experimental results indicate that the novel algorithm can reach a better segmentation quality and the processing time of each image is reduced.They enhance efficiency and satisfy the requirements of a highly effective,real-time AUV. 展开更多
关键词 underwater image image segmentation autonomous underwater vehicle (AUV) gray-scale histogram fuzzy C-means real-time effectiveness sine function particle swarm optimization (PSO)
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An algorithm for moving target detection in IR image based on grayscale distribution and kernel function 被引量:6
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作者 王鲁平 张路平 +1 位作者 赵明 李飚 《Journal of Central South University》 SCIE EI CAS 2014年第11期4270-4278,共9页
A fast algorithm based on the grayscale distribution of infrared target and the weighted kernel function was proposed for the moving target detection(MTD) in dynamic scene of image series. This algorithm is used to de... A fast algorithm based on the grayscale distribution of infrared target and the weighted kernel function was proposed for the moving target detection(MTD) in dynamic scene of image series. This algorithm is used to deal with issues like the large computational complexity, the fluctuation of grayscale, and the noise in infrared images. Four characteristic points were selected by analyzing the grayscale distribution in infrared image, of which the series was quickly matched with an affine transformation model. The image was then divided into 32×32 squares and the gray-weighted kernel(GWK) for each square was calculated. At last, the MTD was carried out according to the variation of the four GWKs. The results indicate that the MTD can be achieved in real time using the algorithm with the fluctuations of grayscale and noise can be effectively suppressed. The detection probability is greater than 90% with the false alarm rate lower than 5% when the calculation time is less than 40 ms. 展开更多
关键词 moving target detection gray-weighted kernel function dynamic background
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New Contour Detection Model Working on Gray-Scale Image of Blended Yarn Cross-Section
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作者 杨宝娣 陶晨 顾平 《Journal of Donghua University(English Edition)》 EI CAS 2009年第6期611-615,共5页
The traditional Contour Tracing algorithm works on the binary image. It is developed that a new model called Facula Diffusion which can work directly on gray-scaled images according to the principle of human vision. T... The traditional Contour Tracing algorithm works on the binary image. It is developed that a new model called Facula Diffusion which can work directly on gray-scaled images according to the principle of human vision. The diffusion operation is controlled by four factors including approximation, closing, length-limiting, and hit-rate. Based on this model, three shape indices, i. e., dimension index, abnormity index, and fluctuation index, were put forward to describe the shape of objects. The rule of shape indices selection was discussed subsequently. Finally, the fibers in polyester/cotton blended yam are classified and the blending ratio is determined. 展开更多
关键词 blended yarn blending ratio image analysis contour tracing facula diffusion feature index
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Fast Texture Segmentation Based on Semi-Local Region Descriptor and Active Contour 被引量:10
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作者 Nawal Houhou Jean-Philippe Thiran Xavier Bresson 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期445-468,共24页
In this paper, we present an efficient approach for unsupervised segmentation of natural and textural images based on the extraction of image features and a fast active contour segmentation model. We address the probl... In this paper, we present an efficient approach for unsupervised segmentation of natural and textural images based on the extraction of image features and a fast active contour segmentation model. We address the problem of textures where neither the gray-level information nor the boundary information is adequate for object extraction. This is often the case of natural images composed of both homogeneous and textured regions. Because these images cannot be in general directly processed by the gray-level information, we propose a new texture descriptor which intrinsically defines the geometry of textures using semi-local image information and tools from differential geometry. Then, we use the popular Kullback-Leibler distance to design an active contour model which distinguishes the background and textures of interest. The existence of a minimizing solution to the proposed segmentation model is proven. Finally, a texture segmentation algorithm based on the Split-Bregrnan method is introduced to extract meaningful objects in a fast way. Promising synthetic and real-world results for gray-scale and color images are presented. 展开更多
关键词 Semi-local image information Beltrami framework metric tensor active contour Kullback-Leibler distance split-Bregman method.
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