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Multi-modality hierarchical fusion network for lumbar spine segmentation with magnetic resonance images 被引量:1
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作者 Han Yan Guangtao Zhang +1 位作者 Wei Cui Zhuliang Yu 《Control Theory and Technology》 EI CSCD 2024年第4期612-622,共11页
For the analysis of spinal and disc diseases,automated tissue segmentation of the lumbar spine is vital.Due to the continuous and concentrated location of the target,the abundance of edge features,and individual diffe... For the analysis of spinal and disc diseases,automated tissue segmentation of the lumbar spine is vital.Due to the continuous and concentrated location of the target,the abundance of edge features,and individual differences,conventional automatic segmentation methods perform poorly.Since the success of deep learning in the segmentation of medical images has been shown in the past few years,it has been applied to this task in a number of ways.The multi-scale and multi-modal features of lumbar tissues,however,are rarely explored by methodologies of deep learning.Because of the inadequacies in medical images availability,it is crucial to effectively fuse various modes of data collection for model training to alleviate the problem of insufficient samples.In this paper,we propose a novel multi-modality hierarchical fusion network(MHFN)for improving lumbar spine segmentation by learning robust feature representations from multi-modality magnetic resonance images.An adaptive group fusion module(AGFM)is introduced in this paper to fuse features from various modes to extract cross-modality features that could be valuable.Furthermore,to combine features from low to high levels of cross-modality,we design a hierarchical fusion structure based on AGFM.Compared to the other feature fusion methods,AGFM is more effective based on experimental results on multi-modality MR images of the lumbar spine.To further enhance segmentation accuracy,we compare our network with baseline fusion structures.Compared to the baseline fusion structures(input-level:76.27%,layer-level:78.10%,decision-level:79.14%),our network was able to segment fractured vertebrae more accurately(85.05%). 展开更多
关键词 Lumbar spine segmentation Deep learning multi-modality fusion Feature fusion
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Optimizing zero-shot text-based segmentation of remote sensing imagery using SAM and Grounding DINO
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作者 Mohanad Diab Polychronis Kolokoussis Maria Antonia Brovelli 《Artificial Intelligence in Geosciences》 2025年第1期14-24,共11页
The use of AI technologies in remote sensing(RS)tasks has been the focus of many individuals in both the professional and academic domains.Having more accessible interfaces and tools that allow people of little or no ... The use of AI technologies in remote sensing(RS)tasks has been the focus of many individuals in both the professional and academic domains.Having more accessible interfaces and tools that allow people of little or no experience to intuitively interact with RS data of multiple formats is a potential provided by this integration.However,the use of AI and AI agents to help automate RS-related tasks is still in its infancy stage,with some frameworks and interfaces built on top of well-known vision language models(VLM)such as GPT-4,segment anything model(SAM),and grounding DINO.These tools do promise and draw guidelines on the potentials and limitations of existing solutions concerning the use of said models.In this work,the state of the art AI foundation models(FM)are reviewed and used in a multi-modal manner to ingest RS imagery input and perform zero-shot object detection using natural language.The natural language input is then used to define the classes or labels the model should look for,then,both inputs are fed to the pipeline.The pipeline presented in this work makes up for the shortcomings of the general knowledge FMs by stacking pre-processing and post-processing applications on top of the FMs;these applications include tiling to produce uniform patches of the original image for faster detection,outlier rejection of redundant bounding boxes using statistical and machine learning methods.The pipeline was tested with UAV,aerial and satellite images taken over multiple areas.The accuracy for the semantic segmentation showed improvement from the original 64%to approximately 80%-99%by utilizing the pipeline and techniques proposed in this work.GitHub Repository:MohanadDiab/LangRS. 展开更多
关键词 Foundation models multi-modal models Vision language models Semantic segmentation segment anything model Earth observation Remote sensing
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Non-contact radar-based HRV monitoring method using adaptive cycle segmentation and peak extraction
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作者 GAO Yixuan ZHU Xinxing +5 位作者 LI Mingchao WU Enkang GU Xiaofeng WANG Cong YU Tian LIANG Junge 《Journal of Measurement Science and Instrumentation》 2025年第2期161-172,共12页
Heart rate variability(HRV),as a key indicator for evaluating autonomic nervous system function,has significant value in areas such as cardiovascular disease screening and emotion monitoring.Although traditional conta... Heart rate variability(HRV),as a key indicator for evaluating autonomic nervous system function,has significant value in areas such as cardiovascular disease screening and emotion monitoring.Although traditional contact-based measurement methods offer high precision,they suffer from issues such as poor comfort and low user compliance.This paper proposes a non-contact HRV monitoring method using frequency modulated continuous wave(FMCW)radar,highlighting adaptive cycle segmentation and peak extraction as core innovations.Key advantages of this method include:1)effective suppression of motion artifacts and respiratory harmonics by leveraging cardiac energy concentration;2)precise heartbeat cycle identification across physiological states via adaptive segmentation,addressing time-varying differences;3)adaptive threshold adjustment using discrete energy signals and a support vector machine(SVM)model based on morphological-temporal-spectral characteristics,reducing complexity while maintaining precision.Previous approaches predominantly process radar signals holistically through algorithms to uniformly extract inter-beat intervals(IBIs),which may result in high computational complexity and inadequate dynamic adaptability.In contrast,our method achieved higher precision than conventional holistic processing approaches,while maintaining comparable precision with lower computational complexity than previous optimization algorithms.Experimental results demonstrate that the system achieves an average IBI error of 8.28 ms(RMSE of 15.3 ms),which is reduced by about 66%compared with the traditional holistically peak seeking method.The average errors of SDNN and RMSSD are 2.65 ms and 4.33 ms,respectively.More than 92%of the IBI errors are controlled within 20 ms.The distance adaptability test showed that although the accuracy of long-distance measurement decreased slightly(<6 ms),the overall detection performance remained robust at different distances.This study provided a novel estimation algorithm for non-contact HRV detection,offering new perspectives for future health monitoring. 展开更多
关键词 HRV FMCW radar cycle segmentation adaptive threshold non-contact monitoring
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Impact of Hard Segment Structures on Fatigue Threshold of Casting Polyurethane Using Cutting Method
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作者 Guang-Zhi Jin Le-Hang Chen +4 位作者 Yu-Zhen Gong Peng Li Run-Guo Wang Fan-Zhu Li Yong-Lai Lu 《Chinese Journal of Polymer Science》 2025年第2期303-315,共13页
The fatigue resistance of casting polyurethane(CPU)is crucial in various sectors,such as construction,healthcare,and the automotive industry.Despite its importance,no studies have reported on the fatigue threshold of ... The fatigue resistance of casting polyurethane(CPU)is crucial in various sectors,such as construction,healthcare,and the automotive industry.Despite its importance,no studies have reported on the fatigue threshold of CPU.This study employed an advanced Intrinsic Strength Analyzer(ISA)to evaluate the fatigue threshold of CPUs,systematically exploring the effects of three types of isocyanates(PPDI,NDI,TDI)that contribute to hard segment structures based on the cutting method.Employing multiple advanced characterization techniques(XRD,TEM,DSC,AFM),the results indicate that PPDI-based polyurethane exhibits the highest fatigue threshold(182.89 J/m^(2))due to a highest phase separation and a densely packed spherulitic structure,although the hydrogen bonding degree is the lowest(48.3%).Conversely,NDI-based polyurethane,despite having the high hydrogen bonding degree(53.6%),exhibits moderate fatigue performance(122.52 J/m^(2)),likely due to a more scattered microstructure.TDI-based polyurethane,with the highest hydrogen bonding degree(59.1%)but absence of spherulitic structure,shows the lowest fatigue threshold(46.43 J/m^(2)).Compared to common rubbers(NR,NBR,EPDM,BR),the superior fatigue performance of CPU is attributed to its well-organized microstructure,polyurethane possesses a higher fatigue threshold due to its high phase separation degree and orderly and dense spherulitic structure which enhances energy dissipation and reduces crack propagation. 展开更多
关键词 Casting polyurethane Fatigue threshold Cutting method Hard segment structures Materials characterization
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Multi-Level Image Segmentation Combining Chaotic Initialized Chimp Optimization Algorithm and Cauchy Mutation
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作者 Shujing Li Zhangfei Li +2 位作者 Wenhui Cheng Chenyang Qi Linguo Li 《Computers, Materials & Continua》 SCIE EI 2024年第8期2049-2063,共15页
To enhance the diversity and distribution uniformity of initial population,as well as to avoid local extrema in the Chimp Optimization Algorithm(CHOA),this paper improves the CHOA based on chaos initialization and Cau... To enhance the diversity and distribution uniformity of initial population,as well as to avoid local extrema in the Chimp Optimization Algorithm(CHOA),this paper improves the CHOA based on chaos initialization and Cauchy mutation.First,Sin chaos is introduced to improve the random population initialization scheme of the CHOA,which not only guarantees the diversity of the population,but also enhances the distribution uniformity of the initial population.Next,Cauchy mutation is added to optimize the global search ability of the CHOA in the process of position(threshold)updating to avoid the CHOA falling into local optima.Finally,an improved CHOA was formed through the combination of chaos initialization and Cauchy mutation(CICMCHOA),then taking fuzzy Kapur as the objective function,this paper applied CICMCHOA to natural and medical image segmentation,and compared it with four algorithms,including the improved Satin Bowerbird optimizer(ISBO),Cuckoo Search(ICS),etc.The experimental results deriving from visual and specific indicators demonstrate that CICMCHOA delivers superior segmentation effects in image segmentation. 展开更多
关键词 Image segmentation image thresholding chimp optimization algorithm chaos initialization Cauchy mutation
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Multi-task Learning of Semantic Segmentation and Height Estimation for Multi-modal Remote Sensing Images 被引量:3
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作者 Mengyu WANG Zhiyuan YAN +2 位作者 Yingchao FENG Wenhui DIAO Xian SUN 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第4期27-39,共13页
Deep learning based methods have been successfully applied to semantic segmentation of optical remote sensing images.However,as more and more remote sensing data is available,it is a new challenge to comprehensively u... Deep learning based methods have been successfully applied to semantic segmentation of optical remote sensing images.However,as more and more remote sensing data is available,it is a new challenge to comprehensively utilize multi-modal remote sensing data to break through the performance bottleneck of single-modal interpretation.In addition,semantic segmentation and height estimation in remote sensing data are two tasks with strong correlation,but existing methods usually study individual tasks separately,which leads to high computational resource overhead.To this end,we propose a Multi-Task learning framework for Multi-Modal remote sensing images(MM_MT).Specifically,we design a Cross-Modal Feature Fusion(CMFF)method,which aggregates complementary information of different modalities to improve the accuracy of semantic segmentation and height estimation.Besides,a dual-stream multi-task learning method is introduced for Joint Semantic Segmentation and Height Estimation(JSSHE),extracting common features in a shared network to save time and resources,and then learning task-specific features in two task branches.Experimental results on the public multi-modal remote sensing image dataset Potsdam show that compared to training two tasks independently,multi-task learning saves 20%of training time and achieves competitive performance with mIoU of 83.02%for semantic segmentation and accuracy of 95.26%for height estimation. 展开更多
关键词 multi-modAL MULTI-TASK semantic segmentation height estimation convolutional neural network
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Hand segmentation from a single depth image based on histogram threshold selection and shallow CNN 被引量:1
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作者 XU Zhengze ZHANG Wenjun 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第5期675-685,共11页
Real-time hand gesture recognition technology significantly improves the user's experience for virtual reality/augmented reality(VR/AR) applications, which relies on the identification of the orientation of the ha... Real-time hand gesture recognition technology significantly improves the user's experience for virtual reality/augmented reality(VR/AR) applications, which relies on the identification of the orientation of the hand in captured images or videos. A new three-stage pipeline approach for fast and accurate hand segmentation for the hand from a single depth image is proposed. Firstly, a depth frame is segmented into several regions by histogrambased threshold selection algorithm and by tracing the exterior boundaries of objects after thresholding. Secondly, each segmentation proposal is evaluated by a three-layers shallow convolutional neural network(CNN) to determine whether or not the boundary is associated with the hand. Finally, all hand components are merged as the hand segmentation result. Compared with algorithms based on random decision forest(RDF), the experimental results demonstrate that the approach achieves better performance with high-accuracy(88.34% mean intersection over union, mIoU) and a shorter processing time(≤8 ms). 展开更多
关键词 HAND segmentation HISTOGRAM threshold selection convolutional neural network(CNN) depth map
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Segmentation of Head and Neck Tumors Using Dual PET/CT Imaging:Comparative Analysis of 2D,2.5D,and 3D Approaches Using UNet Transformer
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作者 Mohammed A.Mahdi Shahanawaj Ahamad +3 位作者 Sawsan A.Saad Alaa Dafhalla Alawi Alqushaibi Rizwan Qureshi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第12期2351-2373,共23页
The segmentation of head and neck(H&N)tumors in dual Positron Emission Tomography/Computed Tomogra-phy(PET/CT)imaging is a critical task in medical imaging,providing essential information for diagnosis,treatment p... The segmentation of head and neck(H&N)tumors in dual Positron Emission Tomography/Computed Tomogra-phy(PET/CT)imaging is a critical task in medical imaging,providing essential information for diagnosis,treatment planning,and outcome prediction.Motivated by the need for more accurate and robust segmentation methods,this study addresses key research gaps in the application of deep learning techniques to multimodal medical images.Specifically,it investigates the limitations of existing 2D and 3D models in capturing complex tumor structures and proposes an innovative 2.5D UNet Transformer model as a solution.The primary research questions guiding this study are:(1)How can the integration of convolutional neural networks(CNNs)and transformer networks enhance segmentation accuracy in dual PET/CT imaging?(2)What are the comparative advantages of 2D,2.5D,and 3D model configurations in this context?To answer these questions,we aimed to develop and evaluate advanced deep-learning models that leverage the strengths of both CNNs and transformers.Our proposed methodology involved a comprehensive preprocessing pipeline,including normalization,contrast enhancement,and resampling,followed by segmentation using 2D,2.5D,and 3D UNet Transformer models.The models were trained and tested on three diverse datasets:HeckTor2022,AutoPET2023,and SegRap2023.Performance was assessed using metrics such as Dice Similarity Coefficient,Jaccard Index,Average Surface Distance(ASD),and Relative Absolute Volume Difference(RAVD).The findings demonstrate that the 2.5D UNet Transformer model consistently outperformed the 2D and 3D models across most metrics,achieving the highest Dice and Jaccard values,indicating superior segmentation accuracy.For instance,on the HeckTor2022 dataset,the 2.5D model achieved a Dice score of 81.777 and a Jaccard index of 0.705,surpassing other model configurations.The 3D model showed strong boundary delineation performance but exhibited variability across datasets,while the 2D model,although effective,generally underperformed compared to its 2.5D and 3D counterparts.Compared to related literature,our study confirms the advantages of incorporating additional spatial context,as seen in the improved performance of the 2.5D model.This research fills a significant gap by providing a detailed comparative analysis of different model dimensions and their impact on H&N segmentation accuracy in dual PET/CT imaging. 展开更多
关键词 PET/CT imaging tumor segmentation weighted fusion transformer multi-modal imaging deep learning neural networks clinical oncology
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Segmentation of Vessels by Morphological Filters and Dynamic Thresholding 被引量:1
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作者 袁慧晶 肖杰 +1 位作者 王涌天 刘越 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期327-330,共4页
A method of segmenting vessels by morphological filters and dynamic thresholding for digital subtraction angiography (DSA) images is presented. The first step is to reduce the noise and enhance the details of image ... A method of segmenting vessels by morphological filters and dynamic thresholding for digital subtraction angiography (DSA) images is presented. The first step is to reduce the noise and enhance the details of image by using morpholngical operators. The second is to segment vessels by dynamic thresholding combined with global thresholding based on the properties of DSA images. Artificial images and actual images have been tested. Experiment results show that the proposed method is efficient and is of great potential for the segmentation of vessels in medical images. 展开更多
关键词 mathematical morphology segmentation thresholdING VESSELS
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Novel Method to Determine the Image Segmentation Threshold during the Quantitative Test on Meso-structure of Geo-material 被引量:1
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作者 胡启军 CAI Qijie +3 位作者 HE Leping ZHAO Xiang SHI Rendan YE Tao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第6期1408-1412,共5页
As a kind of special material in geotechnical engineering, the mudded weak interlayer plays a crucial part in slope stability. In this paper, we presented a method to determine the threshold value of section micrograp... As a kind of special material in geotechnical engineering, the mudded weak interlayer plays a crucial part in slope stability. In this paper, we presented a method to determine the threshold value of section micrographs of the mudded weak interlayer in slope during its meso-structure qualification process. Some soil tests, scanning electron microscopy(SEM) and image segmentation technology were performed to fulfill our purpose. Specifically, the relation between 3 D-porosity and the threshold was obtained by least square fitting of the threshold-porosity curves and a simplified pore equivalent model. Using this relation and the 3 D-porosity determined by soil experiments, we can figure out the polynomial equation of the threshold value. The threshold values obtained by the other existing methods in literature were employed to validate our present results. 展开更多
关键词 mudded weak interlayer threshold value SEM image segmentation 3D-porosity
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A New Multilevel Thresholding Method Using Swarm Intelligence Algorithm for Image Segmentation 被引量:2
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作者 Sathya P. Duraisamy Ramanujam Kayalvizhi 《Journal of Intelligent Learning Systems and Applications》 2010年第3期126-138,共13页
Thresholding is a popular image segmentation method that converts gray-level image into binary image. The selection of optimum thresholds has remained a challenge over decades. In order to determine thresholds, most m... Thresholding is a popular image segmentation method that converts gray-level image into binary image. The selection of optimum thresholds has remained a challenge over decades. In order to determine thresholds, most methods analyze the histogram of the image. The optimal thresholds are often found by either minimizing or maximizing an objective function with respect to the values of the thresholds. In this paper, a new intelligence algorithm, particle swarm opti-mization (PSO), is presented for multilevel thresholding in image segmentation. This algorithm is used to maximize the Kapur’s and Otsu’s objective functions. The performance of the PSO has been tested on ten sample images and it is found to be superior as compared with genetic algorithm (GA). 展开更多
关键词 Image segmentation MULTILEVEL thresholdING PARTICLE SWARM Optimization
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Fuzzy C Mean Thresholding based Level Set for Automated Segmentation of Skin Lesions 被引量:2
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作者 Ammara Masood Adel Ali Al-Jumaily 《Journal of Signal and Information Processing》 2013年第3期66-71,共6页
Accurate segmentation is an important and challenging task in any computer vision system. It also plays a vital role in computerized analysis of skin lesion images. This paper presents a new segmentation method that c... Accurate segmentation is an important and challenging task in any computer vision system. It also plays a vital role in computerized analysis of skin lesion images. This paper presents a new segmentation method that combines the advan-tages of fuzzy C mean algorithm, thresholding and level set method. 3-class Fuzzy C mean thresholding is applied to initialize level set automatically and also for estimating controlling parameters for level set evolution. Parameters for performance evaluation are presented and segmentation results are compared with some other state-of-the-art segmentation methods. Increased true detection rate and reduced false positive and false negative errors confirm the effectiveness of proposed method for skin cancer detection. 展开更多
关键词 SKIN Cancer segmentation Diagnosis FUZZY thresholdING Level SETS
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Multi-verse Optimizer with Rosenbrock and Diffusion Mechanisms for Multilevel Threshold Image Segmentation from COVID-19 Chest X-Ray Images 被引量:1
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作者 Yan Han Weibin Chen +1 位作者 Ali Asghar Heidari Huiling Chen 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第3期1198-1262,共65页
Coronavirus Disease 2019(COVID-19)is the most severe epidemic that is prevalent all over the world.How quickly and accurately identifying COVID-19 is of great significance to controlling the spread speed of the epidem... Coronavirus Disease 2019(COVID-19)is the most severe epidemic that is prevalent all over the world.How quickly and accurately identifying COVID-19 is of great significance to controlling the spread speed of the epidemic.Moreover,it is essential to accurately and rapidly identify COVID-19 lesions by analyzing Chest X-ray images.As we all know,image segmentation is a critical stage in image processing and analysis.To achieve better image segmentation results,this paper proposes to improve the multi-verse optimizer algorithm using the Rosenbrock method and diffusion mechanism named RDMVO.Then utilizes RDMVO to calculate the maximum Kapur’s entropy for multilevel threshold image segmentation.This image segmentation scheme is called RDMVO-MIS.We ran two sets of experiments to test the performance of RDMVO and RDMVO-MIS.First,RDMVO was compared with other excellent peers on IEEE CEC2017 to test the performance of RDMVO on benchmark functions.Second,the image segmentation experiment was carried out using RDMVO-MIS,and some meta-heuristic algorithms were selected as comparisons.The test image dataset includes Berkeley images and COVID-19 Chest X-ray images.The experimental results verify that RDMVO is highly competitive in benchmark functions and image segmentation experiments compared with other meta-heuristic algorithms. 展开更多
关键词 COVID-19 Multilevel threshold image segmentation Kapur’s entropy Multi-verse optimizer Meta-heuristic algorithm Bionic algorithm
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Defocus Blur Segmentation Using Local Binary Patterns with Adaptive Threshold 被引量:1
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作者 Usman Ali Muhammad Tariq Mahmood 《Computers, Materials & Continua》 SCIE EI 2022年第4期1597-1611,共15页
Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the images.Due to the limited available information about blur type,scenario and the level of blurriness,detection ... Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the images.Due to the limited available information about blur type,scenario and the level of blurriness,detection and segmentation is a challenging task.Hence,the performance of the blur measure operator is an essential factor and needs improvement to attain perfection.In this paper,we propose an effective blur measure based on local binary pattern(LBP)with adaptive threshold for blur detection.The sharpness metric developed based on LBP used a fixed threshold irrespective of the type and level of blur,that may not be suitable for images with variations in imaging conditions,blur amount and type.Contrarily,the proposed measure uses an adaptive threshold for each input image based on the image and blur properties to generate improved sharpness metric.The adaptive threshold is computed based on the model learned through support vector machine(SVM).The performance of the proposed method is evaluated using two different datasets and is compared with five state-of-the-art methods.Comparative analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all of the compared methods. 展开更多
关键词 Adaptive threshold blur measure defocus blur segmentation local binary pattern support vector machine
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TFM imaging of aeroengine casing ring forgings with curved surfaces using acoustic field threshold segmentation and vector coherence factor 被引量:1
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作者 Shanyue GUAN Xiaokai WANG +1 位作者 Lin HUA Yixuan LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第11期401-415,共15页
The aeroengine casing ring forgings have complex cross-section shapes,when the conventional ultrasonic or phased array is applied to detect such curved surfaces,the inspection images always have low resolution and eve... The aeroengine casing ring forgings have complex cross-section shapes,when the conventional ultrasonic or phased array is applied to detect such curved surfaces,the inspection images always have low resolution and even artifacts due to the distortion of the wave beam.In this article,taking a type of aeroengine casing ring forging as an example,the Total Focusing Method(TFM)algorithms for curved surfaces are investigated.First,the Acoustic Field Threshold Segmentation(AFTS)algorithm is proposed to reduce background noise and data calculation.Furthermore,the Vector Coherence Factor(VCF)is adopted to improve the lateral resolution of the TFM imaging.Finally,a series of 0.8 mm diameter Side-Drilled Holes(SDHs)are machined below convex and concave surfaces of the specimen.The quantitative comparison of the detection images using the conventional TFM,AFTS-TFM,VCF-TFM,and AFTS-VCF-TFM is implemented in terms of data volume,imaging Signal-to-Noise Ratio(SNR),and defect echo width.The results show that compared with conventional TFM,the data volume of AFTS-VCF-TFM algorithm for convex and concave is decreased by 32.39%and 73.40%,respectively.Moreover,the average SNR of the AFTS-VCF-TFM is gained up to 40.0 dB,while the average 6 dB-drop echo width of defects is reduced to 0.74 mm. 展开更多
关键词 Aeroengine casing Acoustic Field threshold segmentation(AFTS) Curved surfaces Total Focusing Method(TFM) Vector Coherence Factor(VCF)
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A Method of Cracks Image Segmentation Based on the Means of Multiple Thresholds 被引量:4
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作者 Youquan He Hanxing Qiu 《通讯和计算机(中英文版)》 2012年第10期1147-1151,共5页
关键词 图像分割方法 路面裂缝 多阈值 数学形态学 分割阈值 最小误差法 分割算法 最大熵法
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Salp Swarm Algorithm with Multilevel Thresholding Based Brain Tumor Segmentation Model
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作者 Hanan T.Halawani 《Computers, Materials & Continua》 SCIE EI 2023年第3期6775-6788,共14页
Biomedical image processing acts as an essential part of severalmedical applications in supporting computer aided disease diagnosis. MagneticResonance Image (MRI) is a commonly utilized imaging tool used tosave glioma... Biomedical image processing acts as an essential part of severalmedical applications in supporting computer aided disease diagnosis. MagneticResonance Image (MRI) is a commonly utilized imaging tool used tosave glioma for clinical examination. Biomedical image segmentation plays avital role in healthcare decision making process which also helps to identifythe affected regions in the MRI. Though numerous segmentation models areavailable in the literature, it is still needed to develop effective segmentationmodels for BT. This study develops a salp swarm algorithm with multi-levelthresholding based brain tumor segmentation (SSAMLT-BTS) model. Thepresented SSAMLT-BTS model initially employs bilateral filtering based onnoise removal and skull stripping as a pre-processing phase. In addition,Otsu thresholding approach is applied to segment the biomedical imagesand the optimum threshold values are chosen by the use of SSA. Finally,active contour (AC) technique is used to identify the suspicious regions in themedical image. A comprehensive experimental analysis of the SSAMLT-BTSmodel is performed using benchmark dataset and the outcomes are inspectedin many aspects. The simulation outcomes reported the improved outcomesof the SSAMLT-BTS model over recent approaches with maximum accuracyof 95.95%. 展开更多
关键词 Brain tumor segmentation noise removal multilevel thresholding healthcare PRE-PROCESSING
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Quantum watermarking based on threshold segmentation using quantum informational entropy
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作者 Jia Luo Ri-Gui Zhou +2 位作者 Wen-Wen Hu YaoChong Li Gao-Feng Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期116-122,共7页
We propose a new quantum watermarking scheme based on threshold selection using informational entropy of quantum image.The core idea of this scheme is to embed information into object and background of cover image in ... We propose a new quantum watermarking scheme based on threshold selection using informational entropy of quantum image.The core idea of this scheme is to embed information into object and background of cover image in different ways.First,a threshold method adopting the quantum informational entropy is employed to determine a threshold value.The threshold value can then be further used for segmenting the cover image to a binary image,which is an authentication key for embedding and extraction information.By a careful analysis of the quantum circuits of the scheme,that is,translating into the basic gate sequences which show the low complexity of the scheme.One of the simulation-based experimental results is entropy difference which measures the similarity of two images by calculating the difference in quantum image informational entropy between watermarked image and cover image.Furthermore,the analyses of peak signal-to-noise ratio,histogram and capacity of the scheme are also provided. 展开更多
关键词 quantum image watermarking threshold segmentation quantum informational entropy quantum circuit
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The Method of Flotation Froth Image Segmentation Based on Threshold Level Set
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作者 Ji Zhao Huibin Wang +1 位作者 Lina Zhang Conghui Wang 《Advances in Molecular Imaging》 2015年第2期38-48,共11页
A novel flotation froth image segmentation based on threshold level set method is put forward in view of the problem of over-segmentation and under-segmentation which occurs when the existing method segmented the flot... A novel flotation froth image segmentation based on threshold level set method is put forward in view of the problem of over-segmentation and under-segmentation which occurs when the existing method segmented the flotation froth images. Firstly, the proposed method adopts histogram equalization to improve the contrast of the image, and then chooses the upper threshold and lower threshold from grey value of histogram of the image equalization, and complete image segmentation using the level set method. In this paper, the model which integrates edge with region level set model is utilized, and the speed energy term is introduced to segment the target. Experimental results show that the proposed method has better segmentation results and higher segmentation efficiency on the images with under-segmentation and incorrect segmentation, and it is meaningful for ore dressing industrial. 展开更多
关键词 FLOTATION Froth Image segmentation Active CONTOUR Model HISTOGRAM EQUALIZATION Speed Function threshold Level Set
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A Semi-Vectorial Hybrid Morphological Segmentation of Multicomponent Images Based on Multithreshold Analysis of Multidimensional Compact Histogram 被引量:1
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作者 Adles Kouassi Sié Ouattara +2 位作者 Jean-Claude Okaingni Wognin J. Vangah Alain Clement 《Open Journal of Applied Sciences》 2017年第11期597-610,共14页
In this work, we propose an original approach of semi-vectorial hybrid morphological segmentation for multicomponent images or multidimensional data by analyzing compact multidimensional histograms based on different ... In this work, we propose an original approach of semi-vectorial hybrid morphological segmentation for multicomponent images or multidimensional data by analyzing compact multidimensional histograms based on different orders. Its principle consists first of segment marginally each component of the multicomponent image into different numbers of classes fixed at K. The segmentation of each component of the image uses a scalar segmentation strategy by histogram analysis;we mainly count the methods by searching for peaks or modes of the histogram and those based on a multi-thresholding of the histogram. It is the latter that we have used in this paper, it relies particularly on the multi-thresholding method of OTSU. Then, in the case where i) each component of the image admits exactly K classes, K vector thresholds are constructed by an optimal pairing of which each component of the vector thresholds are those resulting from the marginal segmentations. In addition, the multidimensional compact histogram of the multicomponent image is computed and the attribute tuples or ‘colors’ of the histogram are ordered relative to the threshold vectors to produce (K + 1) intervals in the partial order giving rise to a segmentation of the multidimensional histogram into K classes. The remaining colors of the histogram are assigned to the closest class relative to their center of gravity. ii) In the contrary case, a vectorial spatial matching between the classes of the scalar components of the image is produced to obtain an over-segmentation, then an interclass fusion is performed to obtain a maximum of K classes. Indeed, the relevance of our segmentation method has been highlighted in relation to other methods, such as K-means, using unsupervised and supervised quantitative segmentation evaluation criteria. So the robustness of our method relatively to noise has been tested. 展开更多
关键词 MORPHOLOGICAL segmentation Vectorial Orders Semi-Vectorial segmentation MULTIDIMENSIONAL COMPACT HISTOGRAM Multi-thresholds Fusion Inter-Class Classification
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