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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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Improving Image Copy-Move Forgery Detection with Particle Swarm Optimization Techniques 被引量:7
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作者 SHI Wenchang ZHAO Fei +1 位作者 QIN Bo LIANG Bin 《China Communications》 SCIE CSCD 2016年第1期139-149,共11页
Copy-Move Forgery(CMF) is one of the simple and effective operations to create forged digital images.Recently,techniques based on Scale Invariant Features Transform(SIFT) are widely used to detect CMF.Various approach... Copy-Move Forgery(CMF) is one of the simple and effective operations to create forged digital images.Recently,techniques based on Scale Invariant Features Transform(SIFT) are widely used to detect CMF.Various approaches under the SIFT-based framework are the most acceptable ways to CMF detection due to their robust performance.However,for some CMF images,these approaches cannot produce satisfactory detection results.For instance,the number of the matched keypoints may be too less to prove an image to be a CMF image or to generate an accurate result.Sometimes these approaches may even produce error results.According to our observations,one of the reasons is that detection results produced by the SIFT-based framework depend highly on parameters whose values are often determined with experiences.These values are only applicable to a few images,which limits their application.To solve the problem,a novel approach named as CMF Detection with Particle Swarm Optimization(CMFDPSO) is proposed in this paper.CMFD-PSO integrates the Particle Swarm Optimization(PSO) algorithm into the SIFT-based framework.It utilizes the PSO algorithm to generate customized parameter values for images,which are used for CMF detection under the SIFT-based framework.Experimental results show that CMFD-PSO has good performance. 展开更多
关键词 copy-move forgery detection SIFT region duplication digital image forensics
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SOFT IMAGE SEGMENTATION BASED ON CENTER-FREE FUZZY CLUSTERING 被引量:2
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作者 马儒宁 朱燕 丁军娣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第1期67-76,共10页
Image segmentation remains one of the major challenges in image analysis.And soft image segmentation has been widely used due to its good effect.Fuzzy clustering algorithms are very popular in soft segmentation.A new ... Image segmentation remains one of the major challenges in image analysis.And soft image segmentation has been widely used due to its good effect.Fuzzy clustering algorithms are very popular in soft segmentation.A new soft image segmentation method based on center-free fuzzy clustering is proposed.The center-free fuzzy clustering is the modified version of the classical fuzzy C-means ( FCM ) clustering.Different from traditional fuzzy clustering , the center-free fuzzy clustering does not need to calculate the cluster center , so it can be applied to pairwise relational data.In the proposed method , the mean-shift method is chosen for initial segmentation firstly , then the center-free clustering is used to merge regions and the final segmented images are obtained at last.Experimental results show that the proposed method is better than other image segmentation methods based on traditional clustering. 展开更多
关键词 soft image segmentationl fuzzy clusteringl center-free clusteringI region merging
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More efficient ground truth ROI image coding technique: implementation and wavelet based application analysis 被引量:5
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作者 KUMARAYAPA Ajith 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期835-840,共6页
In this paper, more efficient, low-complexity and reliable region of interest (ROI) image codec for compressing smooth low texture remote sensing images is proposed. We explore the efficiency of the modified RO! cod... In this paper, more efficient, low-complexity and reliable region of interest (ROI) image codec for compressing smooth low texture remote sensing images is proposed. We explore the efficiency of the modified RO! codec with respect to the selected set of convenient wavelet filters, which is a novel method. Such ROI coding experiment analysis representing low bit rate lossy to high quality lossless reconstruction with timing analysis is useful for improving remote sensing ground truth surveillance efficiency in terms of time and quality. The subjective [i.e. fair, five observer (HVS) evaluations using enhanced 3D picture view Hyper memory display technology] and the objective results revealed that for faster ground truth ROI coding applications, the Symlet-4 adaptation performs better than Biorthogonal 4.4 and Biorthogonal 6.8. However, the discrete Meyer wavelet adaptation is the best solution for delayed ROI image reconstructions. 展开更多
关键词 Smooth low texture remote sensing (SLTRS) image Modified region of interest (ROI) image codec Wavelet filters Low bit rate (LBR). High bit rate (HBR). ROI coding
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Susceptibility-weighted imaging is suitable for evaluating signal strength in different brain regions of a rabbit model of acute hemorrhagic anemia 被引量:2
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作者 Jun Xia Ni Xie +3 位作者 Anyu Yin Guozhao Teng Fan Lin Yi Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第9期990-992,共3页
Acute hemorrhagic anemia can decrease blood flow and oxygen supply to brain, and affect its physiological function. While detecting changes in brain function in patients with acute hemorrhagic anemia is helpful for pr... Acute hemorrhagic anemia can decrease blood flow and oxygen supply to brain, and affect its physiological function. While detecting changes in brain function in patients with acute hemorrhagic anemia is helpful for preventing neurological complications and evaluating therapeutic effects, clinical changes in the nervous systems of these patients have not received much attention. In part, this is because current techniques can only indirectly detect changes in brain function following onset of anemia, which leads to lags between real changes in brain function and their detection. 展开更多
关键词 Susceptibility-weighted imaging is suitable for evaluating signal strength in different brain regions of a rabbit model of acute hemorrhagic anemia Figure
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Spatial assessment of forest cover and land-use changes in the Hindu-Kush mountain ranges of northern Pakistan 被引量:5
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作者 Sami ULLAH Muhammad FAROOQ +3 位作者 Muhammad SHAFIQUE Muhammad Afra SIYAB Fazli KAREEM Matthias DEES 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1229-1237,共9页
Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and ... Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and forecast forest cover and other land-use changes for the protection and conservation of mountainous environment. The present study deals with the assessment of forest cover and other land-use changes in the mountain ranges of Dir Kohistan in northern Pakistan, using high resolution multi-temporal SPOT-5 satellite images. The SPOT-5 satellite images of years 2004, 2007, 2010 and 2013 were acquired and classified into land-cover units. In addition, forest cover and land-use change detection map was developed using the classified maps of 2004 and 2013. The classified maps were verified through random field samples and Google Earth imagery(Quick birds and SPOT-5). The results showed that during the period 2004 to 2013 the area of forest land decreased by 6.4%, however, area of range land and agriculture land have increased by 22.1% and 2.9%, respectively. Similarly, barren land increased by 1.1%, whereas, area of snow cover/glacier is significantly decreased by 21.3%. The findings from the study will be useful for forestry and landscape planning and can be utilized by the local, provincial and national forest departments; and REDD+ policy makers in Pakistan. 展开更多
关键词 Forest cover changes Land use changes Remote sensing Hindu-Kush Mountain regions SPOT satellite images
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Evidence of cortical reorganization of language networks after stroke with subacute Broca's aphasia:a blood oxygenation level dependent-functional magnetic resonance imaging study 被引量:8
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作者 Wei-hong Qiu Hui-xiang Wu +7 位作者 Qing-lu Yang Zhuang Kang Zhao-cong Chen Kui Li Guo-rong Qiu Chun-qing Xie Gui-fang Wan Shao-qiong Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第1期109-117,共9页
Aphasia is an acquired language disorder that is a common consequence of stroke.The pathogenesis of the disease is not fully understood,and as a result,current treatment options are not satisfactory.Here,we used blood... Aphasia is an acquired language disorder that is a common consequence of stroke.The pathogenesis of the disease is not fully understood,and as a result,current treatment options are not satisfactory.Here,we used blood oxygenation level-dependent functional magnetic resonance imaging to evaluate the activation of bilateral cortices in patients with Broca's aphasia 1 to 3 months after stroke.Our results showed that language expression was associated with multiple brain regions in which the right hemisphere participated in the generation of language.The activation areas in the left hemisphere of aphasia patients were significantly smaller compared with those in healthy adults.The activation frequency,volumes,and intensity in the regions related to language,such as the left inferior frontal gyrus(Broca's area),the left superior temporal gyrus,and the right inferior frontal gyrus(the mirror region of Broca's area),were lower in patients compared with healthy adults.In contrast,activation in the right superior temporal gyrus,the bilateral superior parietal lobule,and the left inferior temporal gyrus was stronger in patients compared with healthy controls.These results suggest that the right inferior frontal gyrus plays a role in the recovery of language function in the subacute stage of stroke-related aphasia by increasing the engagement of related brain areas. 展开更多
关键词 nerve regeneration functional magnetic resonance imaging cortical functional connectivity language regions neuroplasticity Perisylvian language regions brain activation right hemisphere picture-naming task neural regeneration
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3D Urban Visualization with LOD Techniques
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作者 Wang Yin-xing Li Bai-ying +1 位作者 Liu Wen-bao Shi Xing-xi 《Journal of China University of Mining and Technology》 EI 2006年第1期64-67,共4页
In 3D urban visualization, large data volumes related to buildings are a major factor that limits the delivery and browsing speed in a web-based computer system. This paper proposes a new approach based on the level o... In 3D urban visualization, large data volumes related to buildings are a major factor that limits the delivery and browsing speed in a web-based computer system. This paper proposes a new approach based on the level of detail (LOD) technique advanced in 3D visualization in computer graphics. The key idea of LOD technique is to generalize details of object surfaces without losing details for delivery and displaying objects. This technique has been successfully used in visualizing one or a few multiple objects in films and other industries. However, applying the technique to 3D urban visualization requires an effective generalization method for urban buildings. Conventional two-dimensional (2D) generalization method at different scales provides a good generalization reference for 3D urban visualization, Yet, it is difficult to determine when and where to retrieve data for displaying buildings. To solve this problem, this paper defines an imaging scale point and image scale region for judging when and where to get the fight data for visualization. The results show that the average response time of view transformations is much decreased. 展开更多
关键词 digital city level of detail (LOD) GENERALIZATION VISUALIZATION image scale point/region
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Effect of acupuncture plus conventional treatment on brain activity in ischemic stroke patients: a regional homogeneity analysis 被引量:5
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作者 Wu Ping Zeng Fang +10 位作者 Li Yongxin Li Ji Qiu Lihua Qin Wei Luo Lu Yin Canxin Xiong Yan Bai Yu Wang Dan Zhou Yumei Liang Fanrong 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2017年第5期650-658,共9页
OBJECTIVE: To determine differences in cerebral activity evoked by acupuncture and conventional stroke treatment, and identify the treatment targets.METHODS: In total, 21 patients were randomly divided into two groups... OBJECTIVE: To determine differences in cerebral activity evoked by acupuncture and conventional stroke treatment, and identify the treatment targets.METHODS: In total, 21 patients were randomly divided into two groups. Group A(11 patients) received both acupuncture and conventional treatment, while group B(10 patients) received conventional treatment only. Resting-state functional magnetic resonance imaging(f MRI) was performed on each participant before and after treatment. Regional homogeneity analysis was performed to investigate the potential mechanism of acupuncture treatment by comparing differences in cerebral activity between treatments.RESULTS: Group A showed higher Re Ho in the frontal lobe(BA6, BA46), supra-marginal gyrus(BA40),middle temporal gyrus(BA21), cerebellum, and insula. Group B showed higher Re Ho in the frontal lobe(BA6) and parietal lobe(BA3, BA7).CONCLUSION: Acupuncture and conventional treatment triggered relatively different clinical efficacy and brain responses. Acupuncture treatment more significantly improved the symptoms of stroke patients. More marked changes in sensory,emotional, and motor areas(including the frontal lobe, middle temporal gyrus, cerebellum, and insula) might reflect the specific acupuncture mechanism. 展开更多
关键词 Acupuncture Magnetic resonance imaging Stroke Cerebral activity regional homogeneity analysis
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Local synchronization and amplitude of the fluctuation of spontaneous brain activity in attention-deficit/hyperactivity disorder:a resting-state fMRI study 被引量:25
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作者 Li An Qing-Jiu Cao +4 位作者 Man-Qiu Sui Li Sun Qi-Hong Zou Yu-Feng Zang Yu-Feng Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2013年第5期603-613,共11页
Regional homogeneity(ReHo)and the amplitude of low-frequency fluctuation(ALFF)are two approaches to depicting different regional characteristics of resting-state functional magnetic resonance imaging(RS-fMRI)dat... Regional homogeneity(ReHo)and the amplitude of low-frequency fluctuation(ALFF)are two approaches to depicting different regional characteristics of resting-state functional magnetic resonance imaging(RS-fMRI)data.Whether they can complementarily reveal brain regional functional abnormalities in attention-deficit/hyperactivity disorder(ADHD)remains unknown.In this study,we applied ReHo and ALFF to 23 medication-na ve boys diagnosed with ADHD and 25 age-matched healthy male controls using whole-brain voxel-wise analysis.Correlation analyses were conducted in the ADHD group to investigate the relationship between the regional spontaneous brain activity measured by the two approaches and the clinical symptoms of ADHD.We found that the ReHo method showed widely-distributed differences between the two groups in the fronto-cingulo-occipitocerebellar circuitry,while the ALFF method showed a difference only in the right occipital area.When a larger smoothing kernel and a more lenient threshold were used for ALFF,more overlapped regions were found between ALFF and ReHo,and ALFF even found some new regions with group differences.The ADHD symptom scores were correlated with the ReHo values in the right cerebellum,dorsal anterior cingulate cortex and left lingual gyrus in the ADHD group,while no correlation was detected between ALFF and ADHD symptoms.In conclusion,ReHo may be more sensitive to regional abnormalities,at least in boys with ADHD,than ALFF.And ALFF may be complementary to ReHo in measuring local spontaneous activity.Combination of the two may yield a more comprehensive pathophy-siological framework for ADHD. 展开更多
关键词 resting state functional magnetic resonance imaging regional homogeneity amplitude of low-frequency fluctuation attention-deficit/hyperactivity disorder
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