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A fast algorithm for computing moments of gray images based on NAM and extended shading approach 被引量:6
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作者 Yunping Zheng (1) zhengyp@scut.edu.cn Mudar Sarem (2) 《Frontiers of Computer Science》 SCIE EI CSCD 2011年第1期57-65,共9页
Computing moments on images is very important in the fields of image processing and pattern recognition. The non-symmetry and anti-packing model (NAM) is a general pattern representation model that has been develope... Computing moments on images is very important in the fields of image processing and pattern recognition. The non-symmetry and anti-packing model (NAM) is a general pattern representation model that has been developed to help design some efficient image representation methods. In this paper, inspired by the idea of computing moments based on the S-Tree coding (STC) representation and by using the NAM and extended shading (NAMES) approach, we propose a fast algorithm for computing lower order moments based on the NAMES representation, which takes O(N) time where N is the number of NAM blocks. By taking three idiomatic standard gray images 'Lena', 'F16', and 'Peppers' in tile field of image processing as typical test objects, and by comparing our proposed algorithm with the conventional algorithm and the popular STC representation algorithm for computing the lower order moments, the theoretical and experimental results presented in this paper show that the average execution time improvement ratios of the proposed NAMES approach over the STC approach, and also the conventional approach are 26.63%, and 82.57% respectively while maintaining the image quality. 展开更多
关键词 moment computation gray image representation Gouraud shading method non-symmetry and antipacking model (NAM) S-Tree coding (STC)
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Real-time digital image stabilization based on regional field image gray projection 被引量:4
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作者 Weiping Yang Zhilong Zhang +3 位作者 Yan Zhang Xinping Lu Jicheng Li Zhiguang Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期224-231,共8页
Digital image stabilization technique plays important roles in video surveillance and object acquisition.Many useful electronic image stabilization algorithms have been studied.A real-time algorithm is proposed based ... Digital image stabilization technique plays important roles in video surveillance and object acquisition.Many useful electronic image stabilization algorithms have been studied.A real-time algorithm is proposed based on field image gray projection which enables the regional odd and even field image to be projected into x and y directions and thus to get the regional gray projection curves in x and y directions,respectively.For the odd field image channel,motion parameters can be estimated via iterative minimum absolute difference based on two successive field image regional gray projection curves.Then motion compensations can be obtained after using the Kalman filter method.Finally,the odd field image is adjusted according to the compensations.In the mean time,motion compensation is applied to the even field image channel with the odd field image gray projection curves of the current frame.By minimizing absolute difference between odd and even field image gray projection curves of the current frame,the inter-field motion parameters can be estimated.Therefore,the even field image can be adjusted by combining the inter-field motion parameters and the odd field compensations.Finally,the stabilized image sequence can be obtained by synthesizing the adjusted odd and even field images.Experimental results show that the proposed algorithm can run in real-time and have a good stabilization performance.In addition,image blurring can be improved. 展开更多
关键词 image dithering field based processing electronic image stabilization regional gray projection minimum absolute difference.
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A Secure Robust Gray Scale Image Steganography Using Image Segmentation
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作者 Mohammed J. Bawaneh Atef A. Obeidat 《Journal of Information Security》 2016年第3期152-164,共13页
Steganography is the art of hiding a secret message in some kind of media. The main goal is not to hide only the secret message but also the existence of communication and secure data transferring. There are a lot of ... Steganography is the art of hiding a secret message in some kind of media. The main goal is not to hide only the secret message but also the existence of communication and secure data transferring. There are a lot of methods that were utilized for building the steganography;such as LSB (Least Significant Bits), Discrete Cosine Transform (DCT), Discrete Fourier Transform, Spread-Spectrum Encoding, and Perceptual Masking, but all of them are challenged by steganalysis. This paper proposes a new technique for Gray Scale Image Steganography that uses the idea of image segmentation and LSB to deal with such problem. The proposed method deals with different types of images by converting them to a virtual gray scale 24 bitmaps, finds out the possible segments inside image and then computes the possible areas for each segment with boundaries. Any intruder trying to find the transformed image will not be able to understand it without the correct knowledge about the transformation process. The knowledge is represented by the key of image segmentation, key of data distribution inside segment (area selection), key of mapping within each area segment, key agreement of cryptography method, key of secret message length and key of message extension. Our method is distinguishing oneself by one master key to generate the area selection key, pixels selection keys and cryptography key. Thus, the existence of secret message is hard to be detected by the steganalysis. Experiment results show that the proposed technique satisfied the main requirements of steganography;visual appearance, modification rate, capacity, undetectability, and robustness against extraction (security). Also it achieved the maximum capacity of cover image with a modification rate equals 0.04 and visual quality for stego-image comparable to cover image. 展开更多
关键词 gray Scale image Steganography image Segmentation Random LSB
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An effective fractal image compression algorithm based on plane fitting 被引量:2
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作者 王兴元 国兴 张丹丹 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期149-155,共7页
A new method using plane fitting to decide whether a domain block is similar enough to a given range block is proposed in this paper. First, three coefficients are computed for describing each range and domain block. ... A new method using plane fitting to decide whether a domain block is similar enough to a given range block is proposed in this paper. First, three coefficients are computed for describing each range and domain block. Then, the best-matched one for every range block is obtained by analysing the relation between their coefficients. Experimental results show that the proposed method can shorten encoding time markedly, while the retrieved image quality is still acceptable. In the decoding step, a kind of simple line fitting on block boundaries is used to reduce blocking effects. At the same time, the proposed method can also achieve a high compression ratio. 展开更多
关键词 fractal image compression plane fitting peak signal to noise ratio gray image
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3D Displacement Measurement by White Light Digital Image Analysis in Frequency Domination Area 被引量:1
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作者 计欣华 杨新伟 陈金龙 《Transactions of Tianjin University》 EI CAS 2008年第1期1-6,共6页
In this paper, white light digital image analysis in frequency domination area for measuring 3D displacement is put forward. The measuring system has the characteristics of whole-field, non-contact and omni-bearing me... In this paper, white light digital image analysis in frequency domination area for measuring 3D displacement is put forward. The measuring system has the characteristics of whole-field, non-contact and omni-bearing measurement. It is simple and the coherent light is not demanded. Gray images before and after deformation are recorded using two CCDs at two different shooting angles, then digitalized and analyzed by frequency domination correlation arithmetic. The 2D displacement obtained is used to formulate 3D displacement via mathematical transformation. The experimental plate is 40,mm in length, 30,mm in width and 10 mm in height. The definite displacement is given using a 3D precise adjusting frame. The 3D displacement is calculated and compared with the definite displacement. The error is 4%-11% and the availability of this method was certified. Using this method, the compression deformation of a thin-wall cylinder with 140 mm in height, 64 mm in inner diameter and 64.6,mm in external diameter, was also measured. This method is proper to measure dynamic deformation. 展开更多
关键词 white light 3D displacement gray image
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Extraction of Geometric Features of Wear Particles in Color Ferr ograph Images Based on RGB Color Space 被引量:1
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作者 CHEN Gui-ming, WANG Han-gong, ZHANG Bao-jun, PAN Wei Second Artillery Engineering Institute, Xi′an 710025, P.R.China 《International Journal of Plant Engineering and Management》 2003年第3期171-178,共8页
This paper analyzes the potential color f ormats of ferrograph images, and presents the algorithms of converting the forma ts to RGB(Red, Green, Blue) color space. Through statistical analysis of wear pa rticles′ ge... This paper analyzes the potential color f ormats of ferrograph images, and presents the algorithms of converting the forma ts to RGB(Red, Green, Blue) color space. Through statistical analysis of wear pa rticles′ geometric features of color ferrograph images in the RGB color space, we give the differences of ferrograph wear particles′ geometric features among RGB color spaces and gray scale space, and calculate their respective distributi ons. 展开更多
关键词 ferrograph image RGB image gray image geometri c feature.
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Feature Extraction of Defects on Wood Surface
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作者 王克奇 白景峰 +2 位作者 莫虹 孔详林 崔克冰 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第1期54-56,共3页
The computer image processing technology was used to accomplish the feature extraction of defect images on wood surface. By calculation of gray values of defects. three feature data which are useful to identify the de... The computer image processing technology was used to accomplish the feature extraction of defect images on wood surface. By calculation of gray values of defects. three feature data which are useful to identify the defects have been achieved. The experiment indicates that this way is effective to the automation recognition of the defects on wood surface. 展开更多
关键词 Binarilization gray image Feature extraction
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Morphological changes in gray matter volume correlate with catechol-O-methyl transferase gene Val158Met polymorphism in first-episode treatment-nave patients with schizophrenia 被引量:3
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作者 Ming-Li Li Bo Xiang +12 位作者 Yin-Fei Li Xun Hu Qiang Wang Wan-Jun Guo Wei Lei Chao-Hua Huang Lian-Sheng Zhao Na Li Hong-Yan Ren Hui-Yao Wang Xiao-Hong Ma Wei Deng Tao Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2015年第1期31-42,共12页
The catechol-O-methyltransferase(COMT) gene is a schizophrenia susceptibility gene. A common functional polymorphism of this gene,Val158/158 Met,has been proposed to influence gray matter volume(GMV). However,the ... The catechol-O-methyltransferase(COMT) gene is a schizophrenia susceptibility gene. A common functional polymorphism of this gene,Val158/158 Met,has been proposed to influence gray matter volume(GMV). However,the effects of this polymorphism on cortical thickness/surface area in schizophrenic patients are less clear. In this study,we explored the relationship between the Val158 Met polymorphism of the COMT gene and the GMV/ cortical thickness/cortical surface area in 150 firstepisode treatment-nave patients with schizophrenia and 100 healthy controls. Main effects of diagnosis were found for GMV in the cerebellum and the visual,medial temporal,parietal,and middle frontal cortex. Patients with schizophrenia showed reduced GMVs in these regions. And main effects of genotype were detected for GMV in the left superior frontal gyrus. Moreover,a diagnosis × genotype interaction was found for the GMV of the left precuneus,and the effect of the COMT gene on GMV was due mainly to cortical thickness rather than cortical surface area. In addition,a pattern ofincreased GMV in the precuneus with increasing Met dose found in healthy controls was lost in patients with schizophrenia. These findings suggest that the COMTMet variant is associated with the disruption of dopaminergic influence on gray matter in schizophrenia,and the effect of the COMT gene on GMV in schizophrenia is mainly due to changes in cortical thickness rather than in cortical surface area. 展开更多
关键词 schizophrenia COMT gray matter imaging genetics
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Structural changes in the gray matter of unmedicated patients with obsessive-compulsive disorder: a voxel-based morphometric study 被引量:5
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作者 Ling Tan Qing Fan +6 位作者 Chao You Jijun Wang Zhao Dong Xuemei Wang Kemin Chen Zeping Xiao Kaida Jiang 《Neuroscience Bulletin》 SCIE CAS CSCD 2013年第5期642-648,共7页
The aim of the current study was to use whole brain voxel-based morphometry(VBM)to assess the gray matter(GM)changes in unmedicated patients with obsessive-compulsive disorder(OCD)compared with normal controls.W... The aim of the current study was to use whole brain voxel-based morphometry(VBM)to assess the gray matter(GM)changes in unmedicated patients with obsessive-compulsive disorder(OCD)compared with normal controls.We compared the GM volumes in28 patients with 22 matched healthy controls using a1.5T MRI.Three-dimensional T1-weighted magnetic resonance images were obtained from all participants.VBM was performed to detect GM volume differences between the two groups.We detected increased regional GM volumes in the bilateral middle temporal gyri,bilateral middle occipital gyri,bilateral globus pallidus,right inferior parietal gyrus,left superior parietal gyrus,right parahippocampus,right supramarginal gyrus,right medial superior frontal gyrus,and left inferior frontal opercular cortex in the OCD patients relative to controls(P〈0.001,uncorrected,cluster size〉100 voxels).No decreased GM volume was found in the OCD group compared with normal controls.Our findings suggest that structural changes in the GM are not limited to fronto-striato-thalamic circuits in the pathogenesis of OCD.Temporo-parietal cortex may also play an important role. 展开更多
关键词 obsessive-compulsive disorder magnetic resonance imaging voxel-based morphometry gray matter
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GOOD p-ARY QUASIC-CYCLIC CODES FROM CYCLIC CODES OVER F_p+vF_p 被引量:6
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作者 Minjia SHI Shanlin YANG Shixin ZHU 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第2期375-384,共10页
This paper introduces a Gray map from (Fp + vFp)n to F2pn, and describes the relationship between codes over Fp + vFp and their Gray images. The authors prove that every cyclic code of arbitrary length n over Fp ... This paper introduces a Gray map from (Fp + vFp)n to F2pn, and describes the relationship between codes over Fp + vFp and their Gray images. The authors prove that every cyclic code of arbitrary length n over Fp + vFp is principal, and determine its generator polynomial as well as the number of cyclic codes. Moreover, the authors obtain many best-known p-ary quasic-cyclic codes in terms of their parameters via the Gray map. 展开更多
关键词 Cyclic code generator matrix gray image linear code.
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Biomarkers of preschool children with autism spectrum disorder:quantitative analysis of whole-brain tissue component volumes,intelligence scores,ADOS-CSS,and ages of first-word production and walking onset
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作者 Xiang Zhou Wu-Sheng Lin +6 位作者 Feng-Yun Zou Shuang-Shuang Zhong Ya-Yin Deng Xiao-Wen Luo Li-Shan Shen Shi-Huan Wang Ruo-Mi Guo 《World Journal of Pediatrics》 SCIE 2024年第10期1059-1069,共11页
Background Preschooling is a critical time for intervention in children with autism spectrum disorder(ASD);thus,we analyzed brain tissue component volumes(BTCVs)and clinical indicators in preschool children with ASD t... Background Preschooling is a critical time for intervention in children with autism spectrum disorder(ASD);thus,we analyzed brain tissue component volumes(BTCVs)and clinical indicators in preschool children with ASD to identify new biomarkers for early screening.Methods Eighty preschool children(3–6 years)with ASD were retrospectively included.The whole-brain myelin content(MyC),white matter(WM),gray matter(GM),cerebrospinal fluid(CSF),and non-WM/GM/MyC/CSF brain component volumes were obtained using synthetic magnetic resonance imaging(SyMRI).Clinical data,such as intelligence scores,autism diagnostic observation schedule-calibrated severity scores,age at first production of single words(AFSW),age at first production of phrases(AFP),and age at walking onset(AWO),were also collected.The correlation between the BTCV and clinical data was evaluated,and the effect of BTCVs on clinical data was assessed by a regression model.Results WM and GM volumes were positively correlated with intelligence scores(both P<0.001),but WM and GM did not affect intelligence scores(P=0.116,P=0.290).AWO was positively correlated with AFSW and AFP(both P<0.001).The multivariate linear regression analysis revealed that MyC,AFSW,AFP,and AWO were significantly different(P=0.005,P<0.001,P<0.001).Conclusions This study revealed positive correlations between WM and GM volumes and intelligence scores.Whole-brain MyC affected AFSW,AFP,and AWO in preschool children with ASD.Noninvasive quantification of BTCVs via SyMRI revealed a new visualizable and quantifiable biomarker(abnormal MyC)for early ASD screening in preschool children. 展开更多
关键词 Autism spectrum disorder gray matter-Magnetic resonance imaging Myelin White matter
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