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Pseudo-Semi-Overlap Functions-Based Fuzzy Rough Sets Applied to Image Edge Extraction
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作者 Ran Yin Minge Chen +2 位作者 Yu Liu Yafei Zhao Jianwei Li 《Journal of Applied Mathematics and Physics》 2024年第7期2347-2366,共20页
As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and furth... As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and further extended for applications in image edge extraction. Firstly, a new clustering function, the pseudo-semi-overlap function, is introduced by eliminating the symmetry and right continuity present in the overlap function. The relaxed nature of this function enhances its applicability in image edge extraction. Secondly, the definitions of (I, PSO)-fuzzy rough sets are provided, using (I, PSO)-fuzzy rough sets, a pair of new fuzzy mathematical morphological operators (IPSOFMM operators) is proposed. Finally, by combining the fuzzy C-means algorithm and IPSOFMM operators, a novel image edge extraction algorithm (FCM-IPSO algorithm) is proposed and implemented. Compared to existing algorithms, the FCM-IPSO algorithm exhibits more image edges and a 73.81% decrease in the noise introduction rate. The outstanding performance of (I, PSO)-fuzzy rough sets in image edge extraction demonstrates their practical application value. 展开更多
关键词 Pseudo-Semi-Overlap Functions Fuzzy Rough Set Fuzzy Mathematical Morphology Image edge extraction
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240 nm AlGaN-based deep ultraviolet micro-LEDs:size effect versus edge effect 被引量:2
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作者 Shunpeng Lu Jiangxiao Bai +6 位作者 Hongbo Li Ke Jiang Jianwei Ben Shanli Zhang Zi-Hui Zhang Xiaojuan Sun Dabing Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期55-62,共8页
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef... 240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs. 展开更多
关键词 ALGAN deep ultraviolet micro-LEDs light extraction efficiency size effect edge effect
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Noise‐tolerant matched filter scheme supplemented with neural dynamics algorithm for sea island extraction
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作者 Yiyu Chen Dongyang Fu +3 位作者 Difeng Wang Haoen Huang Yang Si Shangfeng Du 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期996-1013,共18页
Achieving high‐precision extraction of sea islands from high‐resolution satellite remote sensing images is crucial for effective resource development and sustainable management.Unfortunately,achieving such accuracy ... Achieving high‐precision extraction of sea islands from high‐resolution satellite remote sensing images is crucial for effective resource development and sustainable management.Unfortunately,achieving such accuracy for sea island extraction presents significant challenges due to the presence of extensive background interference.A more widely applicable noise‐tolerant matched filter(NTMF)scheme is proposed for sea island extraction based on the MF scheme.The NTMF scheme effectively suppresses the background interference,leading to more accurate and robust sea island extraction.To further enhance the accuracy and robustness of the NTMF scheme,a neural dynamics algorithm is supplemented that adds an error integration feedback term to counter noise interference during internal computer operations in practical applications.Several comparative experiments were conducted on various remote sensing images of sea islands under different noisy working conditions to demonstrate the superiority of the proposed neural dynamics algorithm‐assisted NTMF scheme.These experiments confirm the ad-vantages of using the NTMF scheme for sea island extraction with the assistance of neural dynamics algorithm. 展开更多
关键词 edge detection image classification image recognition shape extraction
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Saliency detection and edge feature matching approach for crater extraction 被引量:2
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作者 An Liu Donghua Zhou +1 位作者 Lixin Chen Maoyin Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第6期1291-1300,共10页
Craters are salient terrain features on planetary surfaces, and provide useful information about the relative dating of geological unit of planets. In addition, they are ideal landmarks for spacecraft navigation. Due ... Craters are salient terrain features on planetary surfaces, and provide useful information about the relative dating of geological unit of planets. In addition, they are ideal landmarks for spacecraft navigation. Due to low contrast and uneven illumination, automatic extraction of craters remains a challenging task. This paper presents a saliency detection method for crater edges and a feature matching algorithm based on edges informa- tion. The craters are extracted through saliency edges detection, edge extraction and selection, feature matching of the same crater edges and robust ellipse fitting. In the edges matching algorithm, a crater feature model is proposed by analyzing the relationship between highlight region edges and shadow region ones. Then, crater edges are paired through the effective matching algorithm. Experiments of real planetary images show that the proposed approach is robust to different lights and topographies, and the detection rate is larger than 90%. 展开更多
关键词 CRATER automatic extraction visual saliency featurematching edge detection.
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Study on Edge Extraction Methods for Image-based Icing On-line Monitoring on Overhead Transmission Lines 被引量:14
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作者 WANG Xiao-peng HU Jian-lin +2 位作者 WU Bin DU Lin SUN Cai-xin 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2687-2693,共7页
A new method of measuring the icing thickness of transmission lines on-line is proposed in this paper.In this method,the pictures of transmission lines which are photoed by the camera on the iron tower are processed i... A new method of measuring the icing thickness of transmission lines on-line is proposed in this paper.In this method,the pictures of transmission lines which are photoed by the camera on the iron tower are processed immediately to extract the edges of the transmission line conductor and transmission line insulators.The icing thickness can be gained by comparing the edges of the iced transmission line and the uniced one.Two icing image edge extraction methods are described in detail,that is,a method based on the combination of the wavelet transform and the floating threshold method and a method based on the combination of the optimal threshold method and the mathematical morphology transform.The icing images from the artificial climatic chamber and transmission lines are used to test the methods above.The results show that the method based on the wavelet transform and the floating threshold method does well in the extraction of relatively smooth edges,such as glaze icing on conductor and icing on the insulator;meanwhile,the method based on the optimal threshold method and the mathematical morphology transform does well in the edge extraction of icing on the conductor,especially the opaque rime icing on the conductor with complicated edges. 展开更多
关键词 输电线路 覆冰层 边缘提取方法 小波转换 图像
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A LUMINANCE EDGE EXTRACTION METHOD USING GRADIENT OF GRAY LEVEL FOR SYNTHETIC APERTURE RADAR IMAGERY
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作者 许蔚 陈宗骘 《Journal of Electronics(China)》 1991年第2期104-115,共12页
In the multistage imaging processing for SAR digital imaging and applications ofSAR imagery,extraction of luminance edge for the SAR imageis often required.It is well studiedto extract the luminance edge for ordinary ... In the multistage imaging processing for SAR digital imaging and applications ofSAR imagery,extraction of luminance edge for the SAR imageis often required.It is well studiedto extract the luminance edge for ordinary images,The methods using gradient are effective andcommonly used.Because of the serious noise of coherent speckle exists in SAR images,somepeople believe that edge extraction by using gradient for SAR imagery gives poor results.Inthis paper,we have derived a rather ideal method for the extraction of luminance edge for SARimagery with the consideration of the characteristics of SAR imagery.This method uses therelative average gradient and combines detection with tracking. 展开更多
关键词 edge extraction SAR IMAGERY MULTISTAGE imaging GRADIENT RELATIVE AVERAGE GRADIENT detection and tracking
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Edge Contour Extraction in MR Image Using Edgeflow Contour Model
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作者 YUAN Da 《Computer Aided Drafting,Design and Manufacturing》 2014年第2期1-5,共5页
This paper presents a new model for edge extraction of MR images, based on curve evolution and edgeflow techniques. At first the model for curve evolution is constructed, which automatically detect boundaries, and cha... This paper presents a new model for edge extraction of MR images, based on curve evolution and edgeflow techniques. At first the model for curve evolution is constructed, which automatically detect boundaries, and change of topology in terms of the edgeflow fields, and then the numerical approximation of the model is introduced, which is based on semi-implicit scheme to speed up the proposed approach. Finally, the numerical implementation is present and the experimental results show that the proposed model successfully extracts the edge contours, regardless of the heavy noise. 展开更多
关键词 MR images edgeflow contour model edge contour extraction
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Sub-pixel extraction of laser stripeand itsapplication in laser plane calibration 被引量:2
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作者 陈平 张志胜 +1 位作者 戴敏 陈恺 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期107-112,共6页
For calibrating the laser plane to implement 3D shape measurement, an algorithm for extracting the laser stripe with sub-pixel accuracy is proposed. The proposed algorithm mainly consists of two stages: two-side edge... For calibrating the laser plane to implement 3D shape measurement, an algorithm for extracting the laser stripe with sub-pixel accuracy is proposed. The proposed algorithm mainly consists of two stages: two-side edge detection and center line extraction. First, the two-side edge of laser stripe is detected using the principal component angle-based progressive probabilistic Hough transform and its width is calculated through the distance between these two edges. Secondly, the center line of laser strip is extracted with 2D Taylor expansion at a sub-pixel level and the laser plane is calibrated with the 3D reconstructed coordinates from the extracted 2D sub-pixel ones. Experimental results demonstrate that the proposed method can not only extract the laser stripe at a high speed, nearly average 78 ms/frame, but also calibrate the coplanar laser stripes at a low error, limited to 0.3 mm. The proposed algorithm can satisfy the system requirement of two-side edge detection and center line extraction, and rapid speed, high precision, as well as strong anti-jamming. 展开更多
关键词 sub-pixel extraction center line extraction laser plane calibration progressive probabilistic Hough transform (PPHT) principal component (PC) angle 2D Taylor expan- sion
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Underwater Sea Cucumber Target Detection Based on Edge-Enhanced Scaling YOLOv4
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作者 Ziting Zhang Hang Zhang +3 位作者 Yue Wang Tonghai Liu Yuxiang He Yunchen Tian 《Journal of Beijing Institute of Technology》 EI CAS 2023年第3期328-340,共13页
Sea cucumber detection is widely recognized as the key to automatic culture.The underwater light environment is complex and easily obscured by mud,sand,reefs,and other underwater organisms.To date,research on sea cucu... Sea cucumber detection is widely recognized as the key to automatic culture.The underwater light environment is complex and easily obscured by mud,sand,reefs,and other underwater organisms.To date,research on sea cucumber detection has mostly concentrated on the distinction between prospective objects and the background.However,the key to proper distinction is the effective extraction of sea cucumber feature information.In this study,the edge-enhanced scaling You Only Look Once-v4(YOLOv4)(ESYv4)was proposed for sea cucumber detection.By emphasizing the target features in a way that reduced the impact of different hues and brightness values underwater on the misjudgment of sea cucumbers,a bidirectional cascade network(BDCN)was used to extract the overall edge greyscale image in the image and add up the original RGB image as the detected input.Meanwhile,the YOLOv4 model for backbone detection is scaled,and the number of parameters is reduced to 48%of the original number of parameters.Validation results of 783images indicated that the detection precision of positive sea cucumber samples reached 0.941.This improvement reflects that the algorithm is more effective to improve the edge feature information of the target.It thus contributes to the automatic multi-objective detection of underwater sea cucumbers. 展开更多
关键词 sea cucumber edge extraction feature enhancement edge-enhanced scaling You Only Look Once-v4(YOLOv4)(ESYv4) model scaling
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Sub-pixel edge detection method for miniature parts in microscopic field of view
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作者 WU Ye-lan QIN Yan-hong ZHANG Zhi-jing 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第1期54-59,共6页
In order to improve the edge detection precision of miniature parts in microscopic field of viewa sub-pixel edge detectionalgorithm combining non-orthogonal quadratic B-spline wavelet transform algorithm and Zernike m... In order to improve the edge detection precision of miniature parts in microscopic field of viewa sub-pixel edge detectionalgorithm combining non-orthogonal quadratic B-spline wavelet transform algorithm and Zernike moment algorithm is proposed.Non-orthogonal quadratic B-spline wavelet transform algorithm is adopted to get the pixel edge of miniature parts?andthe moment invariant of Zernike moment algorithm is used for refining the pixel edge to get sub-pixel edges.A real-time detectionsystem based on the proposed algorithm for miniature parts is established.The general system structure and operational principle are given,the real-time image acquisition and detection are completed,the results of edge detection are analyzed and the detection precision is evaluated.The results show that parts size can be0.01-10mm and the detection precision reaches0.01%-0.1%.Therefore,the edge of the miniature parts can be accurately identified and the detection precision can be improved to sub-pixel level,which meets the requirements of miniature parts precision detection. 展开更多
关键词 miniature parts sub-pixel edge detection wavelet transform Zernike moment
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Fast global motion estimation and moving object extraction algorithm in image sequences 被引量:2
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作者 张涛 费树岷 +1 位作者 李晓东 路红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期192-196,共5页
A novel and effective approach to global motion estimation and moving object extraction is proposed. First, the translational motion model is used because of the fact that complex motion can be decomposed as a sum of ... A novel and effective approach to global motion estimation and moving object extraction is proposed. First, the translational motion model is used because of the fact that complex motion can be decomposed as a sum of translational components. Then in this application, the edge gray horizontal and vertical projections are used as the block matching feature for the motion vectors estimation. The proposed algorithm reduces the motion estimation computations by calculating the onedimensional vectors rather than the two-dimensional ones. Once the global motion is robustly estimated, relatively stationary background can be almost completely eliminated through the inter-frame difference method. To achieve an accurate object extraction result, the higher-order statistics (HOS) algorithm is used to discriminate backgrounds and moving objects. Experimental results validate that the proposed method is an effective way for global motion estimation and object extraction. 展开更多
关键词 global motion estimation edge projection higherorder statistics moving object extraction
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Tip-Edge Plus与Damon托槽对拔牙病例前牙转矩控制的比较 被引量:9
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作者 张建云 李贵凤 +1 位作者 胡小蓓 雷浪 《口腔医学研究》 CAS 北大核心 2017年第5期546-549,共4页
目的:比较Damon自锁托槽与Tip-Edge plus差动直丝弓托槽在拔牙病例中对前牙转矩的控制情况。方法:选取2012~2014年在南京大学附属口腔医院正畸科治疗的拔除4颗前磨牙的患者,分别采用Tip-Edge plus差动直丝弓矫治技术(TP组)和Damon自锁托... 目的:比较Damon自锁托槽与Tip-Edge plus差动直丝弓托槽在拔牙病例中对前牙转矩的控制情况。方法:选取2012~2014年在南京大学附属口腔医院正畸科治疗的拔除4颗前磨牙的患者,分别采用Tip-Edge plus差动直丝弓矫治技术(TP组)和Damon自锁托槽(DM组)矫治技术完成治疗,各20例;拍摄数字化头颅侧位片,测量分析患者治疗前后的变化。结果:治疗前,上颌切牙倾斜度(U1-SN°)两组没有明显差异[TP组(112.45±6.39)°,DM组(111.87±6.33)°];正畸治疗后前牙明显内收,两组上前牙转矩无统计学差异[TP组和DM组分别为(99.32±7.33)°和(99.57±4.74)°];治疗后上下唇突度显著减小,侧貌明显改善,Z角两组之间没有显著差异[TP组和DM组分别为(66.74±10.3)°和(68.11±9.54)°]。结论:Damon自锁托槽与Tip-Edge plus托槽在拔牙病例中都能有效的控制前牙转矩,两组间无明显差异。 展开更多
关键词 Damon自锁托槽 TIP-edge plus托槽 前牙转矩 拔牙病例
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利用Tip-Edge第一期矫治技术非拔牙矫治安氏Ⅱ类1分类错的临床研究 被引量:4
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作者 何欣 张栋梁 李梦华 《口腔医学研究》 CAS CSCD 北大核心 2009年第1期93-95,共3页
目的:应用Tip-Edge I期矫治技术对治疗非拔牙安氏Ⅱ类1分类错进行矫治,并对矫治机理进行探讨。方法:临床筛选病例12例。矫治前后拍摄头颅侧位定位片,并对相关指标进行模型测量。治疗前后相关头影测量项目测量值输入计算机,用SAS软件... 目的:应用Tip-Edge I期矫治技术对治疗非拔牙安氏Ⅱ类1分类错进行矫治,并对矫治机理进行探讨。方法:临床筛选病例12例。矫治前后拍摄头颅侧位定位片,并对相关指标进行模型测量。治疗前后相关头影测量项目测量值输入计算机,用SAS软件包对各测量值进行配对t检验。结果:Tip-Edge I期矫治结束后,上颌切牙倾斜(U1-SN,U1-Apog)明显减小,而下颌切牙的倾斜明显增加(P<0.01)覆牙合超显著减小。上颌第一磨牙远中移动1.5 mm,远中直立3.5°,有显著性差别。模型测量分析表明上颌尖牙间宽度和磨牙宽度显著增加。下颌尖牙间的宽度无显著变化。下颌磨牙宽度显著增加。结论:利用Tip-Edge I期技术能够非拔牙矫治处于生长发育期的安氏Ⅱ类1分类错。对处于生长发育期具有良好生长型(水平生长型)和生长潜力的患者较易取得良好的效果。 展开更多
关键词 TIP-edge 非拔牙矫治 安氏Ⅱ类1分类
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Edge Effect Correction in the S-A Method for Geochemical Anomaly Separation 被引量:31
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作者 Ge Yong Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences & Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Cheng Qiuming Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada +1 位作者 Earth Systems and Mineral Resource Engineering Lab, China University of Geosciences, Wuhan 430074, China Zhang Shenyuan Department of Earth and Atmospheric Science, York University, Toronto, ON, M3J 1P3, Canada Department of Resource and Earth Science, China University of Mining & Technology, Beijing 100083, China 《Journal of China University of Geosciences》 SCIE CSCD 2004年第4期379-387,共9页
Anomaly separation using geochemical data often involves operations in the frequency domain, such as filtering and reducing noise/signal ratios. Unfortunately, the abrupt edge truncation of an image along edges and ho... Anomaly separation using geochemical data often involves operations in the frequency domain, such as filtering and reducing noise/signal ratios. Unfortunately, the abrupt edge truncation of an image along edges and holes (with missing data) often causes frequency distribution distortion in the frequency domain. For example, bright strips are commonly seen in frequency distribution when using a Fourier transform. Such edge effect distortion may affect information extraction results; sometimes severely, depending on the edge abruptness of the image. Traditionally, edge effects are reduced by smoothing the image boundary prior to applying a Fourier transform. Zero-padding is one of the most commonly used smoothing methods. This simple method can reduce the edge effect to some degree but still distorts the image in some cases. Moreover, due to the complexity of geoscience images, which can include irregular shapes and holes with missing data, zero-padding does not always give satisfactory results. This paper proposes the use of decay functions to handle edge effects when extracting information from geoscience images. As an application, this method has been used in a newly developed multifractal method (S-A) for separating geochemical anomalies from background patterns. A geochemical dataset chosen from a mineral district in Nova Scotia, Canada was used to validate the method. 展开更多
关键词 edge effect correction fractal modeling spatial information extraction zero-padding decay functions.
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Feature fusion method for edge detection of color images 被引量:4
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作者 Ma Yu Gu Xiaodong Wang Yuanyuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期394-399,共6页
A novel feature fusion method is proposed for the edge detection of color images. Except for the typical features used in edge detection, the color contrast similarity and the orientation consistency are also selected... A novel feature fusion method is proposed for the edge detection of color images. Except for the typical features used in edge detection, the color contrast similarity and the orientation consistency are also selected as the features. The four features are combined together as a parameter to detect the edges of color images. Experimental results show that the method can inhibit noisy edges and facilitate the detection for weak edges. It has a better performance than conventional methods in noisy environments. 展开更多
关键词 color image processing edge detection feature extraction feature fusion
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Novel histogram descriptor for global feature extraction and description 被引量:3
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作者 张刚 马宗民 +1 位作者 邓立国 徐长明 《Journal of Central South University》 SCIE EI CAS 2010年第3期580-586,共7页
A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. ... A novel histogram descriptor for global feature extraction and description was presented. Three elementary primitives for a 2×2 pixel grid were defined. The complex primitives were computed by matrix transforms. These primitives and equivalence class were used for an image to compute the feature image that consisted of three elementary primitives. Histogram was used for the transformed image to extract and describe the features. Furthermore, comparisons were made among the novel histogram descriptor, the gray histogram and the edge histogram with regard to feature vector dimension and retrieval performance. The experimental results show that the novel histogram can not only reduce the effect of noise and illumination change, but also compute the feature vector of lower dimension. Furthermore, the system using the novel histogram has better retrieval performance. 展开更多
关键词 feature extraction and description histogram descriptor gray histogram edge histogram
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基于Edge Boxes和深度学习的非限制条件下人脸检测 被引量:2
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作者 刘英剑 张起贵 《现代电子技术》 北大核心 2018年第13期29-33,共5页
针对光线、旋转、遮挡、平移等因素对人脸检测结果产生的干扰,提出一种基于Edge Boxes和深度学习相结合的人脸检测算法。首先采用Edge Boxes算法提取出可能存在人脸的边界框,提取边界框中的图像并调整至合适的大小,作为卷积神经网络的输... 针对光线、旋转、遮挡、平移等因素对人脸检测结果产生的干扰,提出一种基于Edge Boxes和深度学习相结合的人脸检测算法。首先采用Edge Boxes算法提取出可能存在人脸的边界框,提取边界框中的图像并调整至合适的大小,作为卷积神经网络的输入,然后利用卷积神经网络对提取出的图像进行特征提取和分类,最后利用非极大抑制算法排除多余人脸检测框,得到人脸的准确位置。该算法应用于LFW和Yale B人脸数据库的检测率分别达到98.7%和98.5%,识别单张人脸的时间均小于0.5 s。实验结果表明,该算法在检测率和检测速率方面较传统算法都有了很大的提高,对于遮挡、光照、旋转等干扰具有更强的鲁棒性。 展开更多
关键词 人脸检测 特征提取 深度学习 edge BOXES 卷积神经网络 非极大抑制算法
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Development of Automatic Extraction Weld for Industrial Radiographic Negative Inspection 被引量:2
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作者 张晓光 林家骏 +1 位作者 李浴 卢印举 《Journal of China University of Mining and Technology》 2003年第1期79-83,共5页
In industrial X-ray inspection, in order to identify weld defects automatically, raise the identification ratio, and avoid processing of complex background, it is an important step for sequent processing to extract we... In industrial X-ray inspection, in order to identify weld defects automatically, raise the identification ratio, and avoid processing of complex background, it is an important step for sequent processing to extract weld from the image. According to the characteristics of weld radiograph image, median filter is adopted to reduce the noise with high frequency, then relative gray-scale of image is chosen as fuzzy characteristic, and image gray-scale fuzzy matrix is constructed and suitable membership function is selected to describe edge characteristic. A fuzzy algorithm is adopted for enhancing radiograph image processing. Based on the intensity distribution characteristic in weld, methodology of weld extraction is then designed. This paper describes the methodology of all the weld extraction, including reducing noise, fuzzy enhancement and weld extraction process. To prove its effectiveness, this methodology was tested with 64 weld negative images available for this study. The experimental results show that this methodology is very effective for extracting linear weld. 展开更多
关键词 industrial X-ray image weld extraction edge fuzzy enhancement
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Feature Extraction to Polar Image 被引量:1
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作者 Donghua Gu Zhenyu Han Qinge Wu 《Journal of Computer and Communications》 2017年第11期16-26,共11页
Some algorithms of feature extraction in existing literature studied for image processing was the gray image with one-dimensional parameter. However, some feature points’ extraction for three-dimensional color of pol... Some algorithms of feature extraction in existing literature studied for image processing was the gray image with one-dimensional parameter. However, some feature points’ extraction for three-dimensional color of polar image, such as the color edge extraction, inflection points, and so on, was urgently to be solved a polar color problem. For achieving quickly and accurately the color feature extraction to polar image, this paper proposed a similar region of color algorithm. The algorithm was compared to polar image, and the effect to color extraction was also described by the combination of the proposed and existing algorithms. Moreover, this paper gave the comparison of the proposed algorithm and an existing classical algorithm to extraction of color feature. These researches in this paper provided a powerful tool for polar image classification, color feature segmentation, precise recognition, and so on. 展开更多
关键词 Similar Region of COLOR Algorithm POLAR IMAGE edge Detection CORNER Point extraction
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Text Extraction and Enhancement of Binary Images Using Cellular Automata
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作者 G. Sahoo Tapas Kumar +1 位作者 B. L. Raina C. M. Bhatia 《International Journal of Automation and computing》 EI 2009年第3期254-260,共7页
Text characters embedded in images represent a rich source of information for content-based indexing and retrieval applications. However, these text characters are difficult to be detected and recognized due to their ... Text characters embedded in images represent a rich source of information for content-based indexing and retrieval applications. However, these text characters are difficult to be detected and recognized due to their various sizes, grayscale values, and complex backgrounds. Existing methods cannot handle well those texts with different contrast or embedded in a complex image background. In this paper, a set of sequential algorithms for text extraction and enhancement of image using cellular automata are proposed. The image enhancement includes gray level, contrast manipulation, edge detection, and filtering. First, it applies edge detection and uses a threshold to filter out for low-contrast text and simplify complex background of high-contrast text from binary image. The proposed algorithm is simple and easy to use and requires only a sample texture binary image as an input. It generates textures with perceived quality, better than those proposed by earlier published techniques. The performance of our method is demonstrated by presenting experimental results for a set of text based binary images. The quality of thresholding is assessed using the precision and recall analysis of the resultant text in the binary image. 展开更多
关键词 Text extraction edge detection cellular automata algorithm text detection thresholding.
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