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A Survey of Crime Scene Investigation Image Retrieval Using Deep Learning
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作者 Ying Liu Aodong Zhou +1 位作者 Jize Xue Zhijie Xu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第4期271-286,共16页
Crime scene investigation(CSI)image is key evidence carrier during criminal investiga-tion,in which CSI image retrieval can assist the public police to obtain criminal clues.Moreover,with the rapid development of deep... Crime scene investigation(CSI)image is key evidence carrier during criminal investiga-tion,in which CSI image retrieval can assist the public police to obtain criminal clues.Moreover,with the rapid development of deep learning,data-driven paradigm has become the mainstreammethod of CSI image feature extraction and representation,and in this process,datasets provideeffective support for CSI retrieval performance.However,there is a lack of systematic research onCSI image retrieval methods and datasets.Therefore,we present an overview of the existing worksabout one-class and multi-class CSI image retrieval based on deep learning.According to theresearch,based on their technical functionalities and implementation methods,CSI image retrievalis roughly classified into five categories:feature representation,metric learning,generative adversar-ial networks,autoencoder networks and attention networks.Furthermore,We analyzed the remain-ing challenges and discussed future work directions in this field. 展开更多
关键词 crime scene investigation(CSI)image image retrieval deep learning
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Performance Evaluation of Super-Resolution Methods Using Deep-Learning and Sparse-Coding for Improving the Image Quality of Magnified Images in Chest Radiographs
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作者 Kensuke Umehara Junko Ota +4 位作者 Naoki Ishimaru Shunsuke Ohno Kentaro Okamoto Takanori Suzuki Takayuki Ishida 《Open Journal of Medical Imaging》 2017年第3期100-111,共12页
Purpose: To detect small diagnostic signals such as lung nodules in chest radiographs, radiologists magnify a region-of-interest using linear interpolation methods. However, such methods tend to generate over-smoothed... Purpose: To detect small diagnostic signals such as lung nodules in chest radiographs, radiologists magnify a region-of-interest using linear interpolation methods. However, such methods tend to generate over-smoothed images with artifacts that can make interpretation difficult. The purpose of this study was to investigate the effectiveness of super-resolution methods for improving the image quality of magnified chest radiographs. Materials and Methods: A total of 247 chest X-rays were sampled from the JSRT database, then divided into 93 training cases with non-nodules and 154 test cases with lung nodules. We first trained two types of super-resolution methods, sparse-coding super-resolution (ScSR) and super-resolution convolutional neural network (SRCNN). With the trained super-resolution methods, the high-resolution image was then reconstructed using the super-resolution methods from a low-resolution image that was down-sampled from the original test image. We compared the image quality of the super-resolution methods and the linear interpolations (nearest neighbor and bilinear interpolations). For quantitative evaluation, we measured two image quality metrics: peak signal-to-noise ratio (PSNR) and structural similarity (SSIM). For comparative evaluation of the super-resolution methods, we measured the computation time per image. Results: The PSNRs and SSIMs for the ScSR and the SRCNN schemes were significantly higher than those of the linear interpolation methods (p p p Conclusion: Super-resolution methods provide significantly better image quality than linear interpolation methods for magnified chest radiograph images. Of the two tested schemes, the SRCNN scheme processed the images fastest;thus, SRCNN could be clinically superior for processing radiographs in terms of both image quality and processing speed. 展开更多
关键词 deep learning SUPER-RESOLUTION SUPER-RESOLUTION Convolutional NEURAL Network (SRCNN) sparse-coding SUPER-RESOLUTION (ScSR) CHEST X-Ray
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A Deep-Learning and Transfer-Learning Hybrid Aerosol Retrieval Algorithm for FY4-AGRI:Development and Verification over Asia
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作者 Disong Fu Hongrong Shi +9 位作者 Christian AGueymard Dazhi Yang Yu Zheng Huizheng Che Xuehua Fan Xinlei Han Lin Gao Jianchun Bian Minzheng Duan Xiangao Xia 《Engineering》 SCIE EI CAS CSCD 2024年第7期164-174,共11页
The Advanced Geosynchronous Radiation Imager(AGRI)is a mission-critical instrument for the Fengyun series of satellites.AGRI acquires full-disk images every 15 min and views East Asia every 5 min through 14 spectral b... The Advanced Geosynchronous Radiation Imager(AGRI)is a mission-critical instrument for the Fengyun series of satellites.AGRI acquires full-disk images every 15 min and views East Asia every 5 min through 14 spectral bands,enabling the detection of highly variable aerosol optical depth(AOD).Quantitative retrieval of AOD has hitherto been challenging,especially over land.In this study,an AOD retrieval algorithm is proposed that combines deep learning and transfer learning.The algorithm uses core concepts from both the Dark Target(DT)and Deep Blue(DB)algorithms to select features for the machinelearning(ML)algorithm,allowing for AOD retrieval at 550 nm over both dark and bright surfaces.The algorithm consists of two steps:①A baseline deep neural network(DNN)with skip connections is developed using 10 min Advanced Himawari Imager(AHI)AODs as the target variable,and②sunphotometer AODs from 89 ground-based stations are used to fine-tune the DNN parameters.Out-of-station validation shows that the retrieved AOD attains high accuracy,characterized by a coefficient of determination(R2)of 0.70,a mean bias error(MBE)of 0.03,and a percentage of data within the expected error(EE)of 70.7%.A sensitivity study reveals that the top-of-atmosphere reflectance at 650 and 470 nm,as well as the surface reflectance at 650 nm,are the two largest sources of uncertainty impacting the retrieval.In a case study of monitoring an extreme aerosol event,the AGRI AOD is found to be able to capture the detailed temporal evolution of the event.This work demonstrates the superiority of the transfer-learning technique in satellite AOD retrievals and the applicability of the retrieved AGRI AOD in monitoring extreme pollution events. 展开更多
关键词 Aerosol optical depth retrieval algorithm deep learning Transfer learning Advanced Geosynchronous Radiation imageR
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Toward Fine-grained Image Retrieval with Adaptive Deep Learning for Cultural Heritage Image 被引量:2
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作者 Sathit Prasomphan 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1295-1307,共13页
Fine-grained image classification is a challenging research topic because of the high degree of similarity among categories and the high degree of dissimilarity for a specific category caused by different poses and scal... Fine-grained image classification is a challenging research topic because of the high degree of similarity among categories and the high degree of dissimilarity for a specific category caused by different poses and scales.A cul-tural heritage image is one of thefine-grained images because each image has the same similarity in most cases.Using the classification technique,distinguishing cultural heritage architecture may be difficult.This study proposes a cultural heri-tage content retrieval method using adaptive deep learning forfine-grained image retrieval.The key contribution of this research was the creation of a retrieval mod-el that could handle incremental streams of new categories while maintaining its past performance in old categories and not losing the old categorization of a cul-tural heritage image.The goal of the proposed method is to perform a retrieval task for classes.Incremental learning for new classes was conducted to reduce the re-training process.In this step,the original class is not necessary for re-train-ing which we call an adaptive deep learning technique.Cultural heritage in the case of Thai archaeological site architecture was retrieved through machine learn-ing and image processing.We analyze the experimental results of incremental learning forfine-grained images with images of Thai archaeological site architec-ture from world heritage provinces in Thailand,which have a similar architecture.Using afine-grained image retrieval technique for this group of cultural heritage images in a database can solve the problem of a high degree of similarity among categories and a high degree of dissimilarity for a specific category.The proposed method for retrieving the correct image from a database can deliver an average accuracy of 85 percent.Adaptive deep learning forfine-grained image retrieval was used to retrieve cultural heritage content,and it outperformed state-of-the-art methods infine-grained image retrieval. 展开更多
关键词 Fine-grained image adaptive deep learning cultural heritage image retrieval
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Triplet Label Based Image Retrieval Using Deep Learning in Large Database 被引量:1
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作者 K.Nithya V.Rajamani 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2655-2666,共12页
Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wi... Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wise label similarity is used tofind the matching images from the database.But this method lacks of limited propose code and weak execution of misclassified images.In order to get-rid of the above problem,a novel triplet based label that incorporates context-spatial similarity measure is proposed.A Point Attention Based Triplet Network(PABTN)is introduced to study propose code that gives maximum discriminative ability.To improve the performance of ranking,a corre-lating resolutions for the classification,triplet labels based onfindings,a spatial-attention mechanism and Region Of Interest(ROI)and small trial information loss containing a new triplet cross-entropy loss are used.From the experimental results,it is shown that the proposed technique exhibits better results in terms of mean Reciprocal Rank(mRR)and mean Average Precision(mAP)in the CIFAR-10 and NUS-WIPE datasets. 展开更多
关键词 image retrieval deep learning point attention based triplet network correlating resolutions classification region of interest
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An Efficient Deep Learning-based Content-based Image Retrieval Framework 被引量:1
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作者 M.Sivakumar N.M.Saravana Kumar N.Karthikeyan 《Computer Systems Science & Engineering》 SCIE EI 2022年第11期683-700,共18页
The use of massive image databases has increased drastically over the few years due to evolution of multimedia technology.Image retrieval has become one of the vital tools in image processing applications.Content-Base... The use of massive image databases has increased drastically over the few years due to evolution of multimedia technology.Image retrieval has become one of the vital tools in image processing applications.Content-Based Image Retrieval(CBIR)has been widely used in varied applications.But,the results produced by the usage of a single image feature are not satisfactory.So,multiple image features are used very often for attaining better results.But,fast and effective searching for relevant images from a database becomes a challenging task.In the previous existing system,the CBIR has used the combined feature extraction technique using color auto-correlogram,Rotation-Invariant Uniform Local Binary Patterns(RULBP)and local energy.However,the existing system does not provide significant results in terms of recall and precision.Also,the computational complexity is higher for the existing CBIR systems.In order to handle the above mentioned issues,the Gray Level Co-occurrence Matrix(GLCM)with Deep Learning based Enhanced Convolution Neural Network(DLECNN)is proposed in this work.The proposed system framework includes noise reduction using histogram equalization,feature extraction using GLCM,similarity matching computation using Hierarchal and Fuzzy c-Means(HFCM)algorithm and the image retrieval using DLECNN algorithm.The histogram equalization has been used for computing the image enhancement.This enhanced image has a uniform histogram.Then,the GLCM method has been used to extract the features such as shape,texture,colour,annotations and keywords.The HFCM similarity measure is used for computing the query image vector's similarity index with every database images.For enhancing the performance of this image retrieval approach,the DLECNN algorithm is proposed to retrieve more accurate features of the image.The proposed GLCM+DLECNN algorithm provides better results associated with high accuracy,precision,recall,f-measure and lesser complexity.From the experimental results,it is clearly observed that the proposed system provides efficient image retrieval for the given query image. 展开更多
关键词 Content based image retrieval(CBIR) improved gray level cooccurrence matrix(GLCM) hierarchal and fuzzy C-means(HFCM)algorithm deep learning based enhanced convolution neural network(DLECNN)
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Historical Arabic Images Classification and Retrieval Using Siamese Deep Learning Model
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作者 Manal M.Khayyat Lamiaa A.Elrefaei Mashael M.Khayyat 《Computers, Materials & Continua》 SCIE EI 2022年第7期2109-2125,共17页
Classifying the visual features in images to retrieve a specific image is a significant problem within the computer vision field especially when dealing with historical faded colored images.Thus,there were lots of eff... Classifying the visual features in images to retrieve a specific image is a significant problem within the computer vision field especially when dealing with historical faded colored images.Thus,there were lots of efforts trying to automate the classification operation and retrieve similar images accurately.To reach this goal,we developed a VGG19 deep convolutional neural network to extract the visual features from the images automatically.Then,the distances among the extracted features vectors are measured and a similarity score is generated using a Siamese deep neural network.The Siamese model built and trained at first from scratch but,it didn’t generated high evaluation metrices.Thus,we re-built it from VGG19 pre-trained deep learning model to generate higher evaluation metrices.Afterward,three different distance metrics combined with the Sigmoid activation function are experimented looking for the most accurate method formeasuring the similarities among the retrieved images.Reaching that the highest evaluation parameters generated using the Cosine distance metric.Moreover,the Graphics Processing Unit(GPU)utilized to run the code instead of running it on the Central Processing Unit(CPU).This step optimized the execution further since it expedited both the training and the retrieval time efficiently.After extensive experimentation,we reached satisfactory solution recording 0.98 and 0.99 F-score for the classification and for the retrieval,respectively. 展开更多
关键词 Visual features vectors deep learning models distance methods similar image retrieval
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Construction of apricot variety search engine based on deep learning
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作者 Chen Chen Lin Wang +8 位作者 Huimin Liu Jing Liu Wanyu Xu Mengzhen Huang Ningning Gou Chu Wang Haikun Bai Gengjie Jia Tana Wuyun 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期387-397,共11页
Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management.... Apricot has a long history of cultivation and has many varieties and types. The traditional variety identification methods are timeconsuming and labor-consuming, posing grand challenges to apricot resource management. Tool development in this regard will help researchers quickly identify variety information. This study photographed apricot fruits outdoors and indoors and constructed a dataset that can precisely classify the fruits using a U-net model (F-score:99%), which helps to obtain the fruit's size, shape, and color features. Meanwhile, a variety search engine was constructed, which can search and identify variety from the database according to the above features. Besides, a mobile and web application (ApricotView) was developed, and the construction mode can be also applied to other varieties of fruit trees.Additionally, we have collected four difficult-to-identify seed datasets and used the VGG16 model for training, with an accuracy of 97%, which provided an important basis for ApricotView. To address the difficulties in data collection bottlenecking apricot phenomics research, we developed the first apricot database platform of its kind (ApricotDIAP, http://apricotdiap.com/) to accumulate, manage, and publicize scientific data of apricot. 展开更多
关键词 APRICOT VARIETY Convolutional neural network deep learning Database platform Mobile application image retrieval
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Refined Sparse Representation Based Similar Category Image Retrieval
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作者 Xin Wang Zhilin Zhu Zhen Hua 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期893-908,共16页
Given one specific image,it would be quite significant if humanity could simply retrieve all those pictures that fall into a similar category of images.However,traditional methods are inclined to achieve high-quality ... Given one specific image,it would be quite significant if humanity could simply retrieve all those pictures that fall into a similar category of images.However,traditional methods are inclined to achieve high-quality retrieval by utilizing adequate learning instances,ignoring the extraction of the image’s essential information which leads to difficulty in the retrieval of similar category images just using one reference image.Aiming to solve this problem above,we proposed in this paper one refined sparse representation based similar category image retrieval model.On the one hand,saliency detection and multi-level decomposition could contribute to taking salient and spatial information into consideration more fully in the future.On the other hand,the cross mutual sparse coding model aims to extract the image’s essential feature to the maximumextent possible.At last,we set up a database concluding a large number of multi-source images.Adequate groups of comparative experiments show that our method could contribute to retrieving similar category images effectively.Moreover,adequate groups of ablation experiments show that nearly all procedures play their roles,respectively. 展开更多
关键词 Similar category image retrieval saliency detection multi-level decomposition cross mutual sparse coding
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Multimodal Fused Deep Learning Networks for Domain Specific Image Similarity Search
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作者 Umer Waqas Jesse Wiebe Visser +1 位作者 Hana Choe Donghun Lee 《Computers, Materials & Continua》 SCIE EI 2023年第4期243-258,共16页
The exponential increase in data over the past fewyears,particularly in images,has led to more complex content since visual representation became the new norm.E-commerce and similar platforms maintain large image cata... The exponential increase in data over the past fewyears,particularly in images,has led to more complex content since visual representation became the new norm.E-commerce and similar platforms maintain large image catalogues of their products.In image databases,searching and retrieving similar images is still a challenge,even though several image retrieval techniques have been proposed over the decade.Most of these techniques work well when querying general image databases.However,they often fail in domain-specific image databases,especially for datasets with low intraclass variance.This paper proposes a domain-specific image similarity search engine based on a fused deep learning network.The network is comprised of an improved object localization module,a classification module to narrow down search options and finally a feature extraction and similarity calculation module.The network features both an offline stage for indexing the dataset and an online stage for querying.The dataset used to evaluate the performance of the proposed network is a custom domain-specific dataset related to cosmetics packaging gathered from various online platforms.The proposed method addresses the intraclass variance problem with more precise object localization and the introduction of top result reranking based on object contours.Finally,quantitative and qualitative experiment results are presented,showing improved image similarity search performance. 展开更多
关键词 image search classification image retrieval deep learning
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Natural Language Processing with Optimal Deep Learning-Enabled Intelligent Image Captioning System
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作者 Radwa Marzouk Eatedal Alabdulkreem +5 位作者 Mohamed KNour Mesfer Al Duhayyim Mahmoud Othman Abu Sarwar Zamani Ishfaq Yaseen Abdelwahed Motwakel 《Computers, Materials & Continua》 SCIE EI 2023年第2期4435-4451,共17页
The recent developments in Multimedia Internet of Things(MIoT)devices,empowered with Natural Language Processing(NLP)model,seem to be a promising future of smart devices.It plays an important role in industrial models... The recent developments in Multimedia Internet of Things(MIoT)devices,empowered with Natural Language Processing(NLP)model,seem to be a promising future of smart devices.It plays an important role in industrial models such as speech understanding,emotion detection,home automation,and so on.If an image needs to be captioned,then the objects in that image,its actions and connections,and any silent feature that remains under-projected or missing from the images should be identified.The aim of the image captioning process is to generate a caption for image.In next step,the image should be provided with one of the most significant and detailed descriptions that is syntactically as well as semantically correct.In this scenario,computer vision model is used to identify the objects and NLP approaches are followed to describe the image.The current study develops aNatural Language Processing with Optimal Deep Learning Enabled Intelligent Image Captioning System(NLPODL-IICS).The aim of the presented NLPODL-IICS model is to produce a proper description for input image.To attain this,the proposed NLPODL-IICS follows two stages such as encoding and decoding processes.Initially,at the encoding side,the proposed NLPODL-IICS model makes use of Hunger Games Search(HGS)with Neural Search Architecture Network(NASNet)model.This model represents the input data appropriately by inserting it into a predefined length vector.Besides,during decoding phase,Chimp Optimization Algorithm(COA)with deeper Long Short Term Memory(LSTM)approach is followed to concatenate the description sentences 4436 CMC,2023,vol.74,no.2 produced by the method.The application of HGS and COA algorithms helps in accomplishing proper parameter tuning for NASNet and LSTM models respectively.The proposed NLPODL-IICS model was experimentally validated with the help of two benchmark datasets.Awidespread comparative analysis confirmed the superior performance of NLPODL-IICS model over other models. 展开更多
关键词 Natural language processing information retrieval image captioning deep learning metaheuristics
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稀疏编码(Sparse coding)在图像检索中的应用 被引量:3
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作者 黄劲 孙洋 徐浩然 《数字技术与应用》 2013年第11期76-77,81,共3页
稀疏编码(Sparse Coding)作为深度学习的一个分支,在机器学习领域取得了多个方面的突破。本文将探索如何将Sparse Coding结合到图像检索的多个模块中,利用Sparse Coding的优点来提高检索的效果。
关键词 图像检索 稀疏编码 深度学习
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Pseudo Zernike Moment and Deep Stacked Sparse Autoencoder for COVID-19 Diagnosis 被引量:1
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作者 Yu-Dong Zhang Muhammad Attique Khan +1 位作者 Ziquan Zhu Shui-Hua Wang 《Computers, Materials & Continua》 SCIE EI 2021年第12期3145-3162,共18页
(Aim)COVID-19 is an ongoing infectious disease.It has caused more than 107.45 m confirmed cases and 2.35 m deaths till 11/Feb/2021.Traditional computer vision methods have achieved promising results on the automatic s... (Aim)COVID-19 is an ongoing infectious disease.It has caused more than 107.45 m confirmed cases and 2.35 m deaths till 11/Feb/2021.Traditional computer vision methods have achieved promising results on the automatic smart diagnosis.(Method)This study aims to propose a novel deep learning method that can obtain better performance.We use the pseudo-Zernike moment(PZM),derived from Zernike moment,as the extracted features.Two settings are introducing:(i)image plane over unit circle;and(ii)image plane inside the unit circle.Afterward,we use a deep-stacked sparse autoencoder(DSSAE)as the classifier.Besides,multiple-way data augmentation is chosen to overcome overfitting.The multiple-way data augmentation is based on Gaussian noise,salt-and-pepper noise,speckle noise,horizontal and vertical shear,rotation,Gamma correction,random translation and scaling.(Results)10 runs of 10-fold cross validation shows that our PZM-DSSAE method achieves a sensitivity of 92.06%±1.54%,a specificity of 92.56%±1.06%,a precision of 92.53%±1.03%,and an accuracy of 92.31%±1.08%.Its F1 score,MCC,and FMI arrive at 92.29%±1.10%,84.64%±2.15%,and 92.29%±1.10%,respectively.The AUC of our model is 0.9576.(Conclusion)We demonstrate“image plane over unit circle”can get better results than“image plane inside a unit circle.”Besides,this proposed PZM-DSSAE model is better than eight state-of-the-art approaches. 展开更多
关键词 Pseudo Zernike moment stacked sparse autoencoder deep learning COVID-19 multiple-way data augmentation medical image analysis
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Convolutional Sparse Coding in Gradient Domain for MRI Reconstruction 被引量:1
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作者 Jiaojiao Xiong Hongyang Lu +1 位作者 Minghui Zhang Qiegen Liu 《自动化学报》 EI CSCD 北大核心 2017年第10期1841-1849,共9页
关键词 梯度图像 稀疏编码 MRI 卷积 应用 分割图像 空间采样 磁共振成像
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基于Sparse Coding和DBN的敏感图像检测
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作者 陈亚楠 黄豫蕾 +1 位作者 唐麟 王士林 《信息安全与通信保密》 2016年第1期113-118,共6页
敏感图像检测,即检测图片是否含有危害青少年健康成长的不良色情信息,对于净化网络环境有重要意义。该文分析了现有的敏感图像检测算法的性能,结合稀疏编码和深度信赖网络,提出了一种改进的敏感图像检测算法。该算法通过稀疏编码来提取... 敏感图像检测,即检测图片是否含有危害青少年健康成长的不良色情信息,对于净化网络环境有重要意义。该文分析了现有的敏感图像检测算法的性能,结合稀疏编码和深度信赖网络,提出了一种改进的敏感图像检测算法。该算法通过稀疏编码来提取特征,将图像切分成标准大小的小图块,然后将其基于字典稀疏表示。接着用max-pooling池化来整合特征,获得最终使用的特征向量。将得到的特征向量输入到DBN网络中进行训练,得到DBN模型。最后将待测图像的特征向量输入到DBN模型中获得分类结果。在文献[10]的数据集上的实验显示,该检测算法较原有算法有较大提升,在以总样本的90%作为训练集时,可获得9.29%的平均错误率。 展开更多
关键词 敏感图像 稀疏编码 深度信赖网络 受限玻尔兹曼机 池化
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Discriminative Structured Dictionary Learning for Image Classification
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作者 王萍 兰俊花 +1 位作者 臧玉卫 宋占杰 《Transactions of Tianjin University》 EI CAS 2016年第2期158-163,共6页
In this paper, a discriminative structured dictionary learning algorithm is presented. To enhance the dictionary's discriminative power, the reconstruction error, classification error and inhomogeneous representat... In this paper, a discriminative structured dictionary learning algorithm is presented. To enhance the dictionary's discriminative power, the reconstruction error, classification error and inhomogeneous representation error are integrated into the objective function. The proposed approach learns a single structured dictionary and a linear classifier jointly. The learned dictionary encourages the samples from the same class to have similar sparse codes, and the samples from different classes to have dissimilar sparse codes. The solution to the objective function is achieved by employing a feature-sign search algorithm and Lagrange dual method. Experimental results on three public databases demonstrate that the proposed approach outperforms several recently proposed dictionary learning techniques for classification. 展开更多
关键词 sparse representation dictionary learning sparse coding image classification
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Two-Level Bregman Method for MRI Reconstruction with Graph Regularized Sparse Coding
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作者 刘且根 卢红阳 张明辉 《Transactions of Tianjin University》 EI CAS 2016年第1期24-34,共11页
In this paper, a two-level Bregman method is presented with graph regularized sparse coding for highly undersampled magnetic resonance image reconstruction. The graph regularized sparse coding is incorporated with the... In this paper, a two-level Bregman method is presented with graph regularized sparse coding for highly undersampled magnetic resonance image reconstruction. The graph regularized sparse coding is incorporated with the two-level Bregman iterative procedure which enforces the sampled data constraints in the outer level and updates dictionary and sparse representation in the inner level. Graph regularized sparse coding and simple dictionary updating applied in the inner minimization make the proposed algorithm converge with a relatively small number of iterations. Experimental results demonstrate that the proposed algorithm can consistently reconstruct both simulated MR images and real MR data efficiently, and outperforms the current state-of-the-art approaches in terms of visual comparisons and quantitative measures. 展开更多
关键词 magnetic resonance imaging graph regularized sparse coding dictionary learning Bregman iterative method alternating direction method
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Content-Based Image Retrieval with Feature Extraction and Rotation Invariance
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作者 Nathanael Okoe Larsey Raphael Mawufemor Kofi Ahiaklo-Kuz Joseph Ncube 《Journal of Computer and Communications》 2022年第4期24-31,共8页
Over recent years, Convolutional Neural Networks (CNN) has improved performance on practically every image-based task, including Content-Based Image Retrieval (CBIR). Nevertheless, since features of CNN have altered o... Over recent years, Convolutional Neural Networks (CNN) has improved performance on practically every image-based task, including Content-Based Image Retrieval (CBIR). Nevertheless, since features of CNN have altered orientation, training a CBIR system to detect and correct the angle is complex. While it is possible to construct rotation-invariant features by hand, retrieval accuracy will be low because hand engineering only creates low-level features, while deep learning methods build high-level and low-level features simultaneously. This paper presents a novel approach that combines a deep learning orientation angle detection model with the CBIR feature extraction model to correct the rotation angle of any image. This offers a unique construction of a rotation-invariant CBIR system that handles the CNN features that are not rotation invariant. This research also proposes a further study on how a rotation-invariant deep CBIR can recover images from the dataset in real-time. The final results of this system show significant improvement as compared to a default CNN feature extraction model without the OAD. 展开更多
关键词 Rotation Invariant CBIR image Orientation Angle Detection Convolutional Neural Network deep learning Real-Time CBIR Information retrieval
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Deep plug-and-play self-supervised neural networks for spectral snapshot compressive imaging
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作者 ZHANG Xing-Yu ZHU Shou-Zheng +4 位作者 ZHOU Tian-Shu QI Hong-Xing WANG Jian-Yu LI Chun-Lai LIU Shi-Jie 《红外与毫米波学报》 CSCD 北大核心 2024年第6期846-857,共12页
The encoding aperture snapshot spectral imaging system,based on the compressive sensing theory,can be regarded as an encoder,which can efficiently obtain compressed two-dimensional spectral data and then decode it int... The encoding aperture snapshot spectral imaging system,based on the compressive sensing theory,can be regarded as an encoder,which can efficiently obtain compressed two-dimensional spectral data and then decode it into three-dimensional spectral data through deep neural networks.However,training the deep neural net⁃works requires a large amount of clean data that is difficult to obtain.To address the problem of insufficient training data for deep neural networks,a self-supervised hyperspectral denoising neural network based on neighbor⁃hood sampling is proposed.This network is integrated into a deep plug-and-play framework to achieve self-supervised spectral reconstruction.The study also examines the impact of different noise degradation models on the fi⁃nal reconstruction quality.Experimental results demonstrate that the self-supervised learning method enhances the average peak signal-to-noise ratio by 1.18 dB and improves the structural similarity by 0.009 compared with the supervised learning method.Additionally,it achieves better visual reconstruction results. 展开更多
关键词 compressed sensing deep learning self-supervised coded aperture imaging
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NeuPh:scalable and generalizable neural phase retrieval with local conditional neural fields
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作者 Hao Wang Jiabei Zhu +2 位作者 Yunzhe Li Qianwan Yang Lei Tian 《Advanced Photonics Nexus》 2024年第5期67-76,共10页
Deep learning has transformed computational imaging,but traditional pixel-based representations limit their ability to capture continuous multiscale object features.Addressing this gap,we introduce a local conditional... Deep learning has transformed computational imaging,but traditional pixel-based representations limit their ability to capture continuous multiscale object features.Addressing this gap,we introduce a local conditional neural field(LCNF)framework,which leverages a continuous neural representation to provide flexible object representations.LCNF’s unique capabilities are demonstrated in solving the highly ill-posed phase retrieval problem of multiplexed Fourier ptychographic microscopy.Our network,termed neural phase retrieval(NeuPh),enables continuous-domain resolution-enhanced phase reconstruction,offering scalability,robustness,accuracy,and generalizability that outperform existing methods.NeuPh integrates a local conditional neural representation and a coordinate-based training strategy.We show that NeuPh can accurately reconstruct high-resolution phase images from low-resolution intensity measurements.Furthermore,NeuPh consistently applies continuous object priors and effectively eliminates various phase artifacts,demonstrating robustness even when trained on imperfect datasets.Moreover,NeuPh improves accuracy and generalization compared with existing deep learning models.We further investigate a hybrid training strategy combining both experimental and simulated datasets,elucidating the impact of domain shift between experiment and simulation.Our work underscores the potential of the LCNF framework in solving complex large-scale inverse problems,opening up new possibilities for deep-learning-based imaging techniques. 展开更多
关键词 neural representation phase retrieval computational imaging deep learning computational microscopy
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