检索结果-内蒙古大学图书馆

Conference on Optical Sensing for Public Safety, Health, and Security

作者： Litwin, D Tjahjadi, T Yang, YH Inst Appl Opt PL-03805 Warsaw Poland

ISBN: (纸本)0819442593

In this paper we present an overview of various strategies for image segmentation, showing their advantages and drawbacks. The overview covers most of the methods from the classical statistical methods to model-based techniques, with a focus on colour images. The paper concludes with a summary of our approach to identifying interreflection.

关键词： image segmentation color image segmentation model-based segmentation interreflection

来源：评论

学校读者我要写书评

暂无评论

Statistical appearance models based on probabilistic correspondences

引用

MEDICAL IMAGE ANALYSIS 2017年 37卷 146-159页

作者： Krueger, Julia Ehrhardt, Jan Handels, Heinz Univ Lubeck Inst Med Informat Lubeck Germany

model-based image analysis is indispensable in medical image processing. One key aspect of building statistical shape and appearance models is the determination of one-to-one correspondences in the training data set. At the same time, the identification of these correspondences is the most challenging part of such methods. In our earlier work, we developed an alternative method using correspondence probabilities instead of exact one-to-one correspondences for a statistical shape model (Hufnagel et al., 2008). In this work, a new approach for statistical appearance models without one-to-one correspondences is proposed. A sparse image representation is used to build a model that combines point position and appearance information at the same time. Probabilistic correspondences between the derived multi-dimensional feature vectors are used to omit the need for extensive preprocessing of finding landmarks and correspondences as well as to reduce the dependence of the generated model on the landmark positions. model generation and model fitting can now be expressed by optimizing a single global criterion derived from a maximum a-posteriori (MAP) approach with respect to model parameters that directly affect both shape and appearance of the considered objects inside the images. The proposed approach describes statistical appearance modeling in a concise and flexible mathematical framework. Besides eliminating the demand for costly correspondence determination, the method allows for additional constraints as topological regularity in the modeling process. In the evaluation the model was applied for segmentation and landmark identification in hand Xray images. The results demonstrate the feasibility of the model to detect hand contours as well as the positions of the joints between finger bones for unseen test images. Further, we evaluated the model on brain data of stroke patients to show the ability of the proposed model to handle partially corrupted data and to demonstrat

关键词： Active appearance model Statistical shape model Probabilistic correspondences model-based segmentation

来源：评论

学校读者我要写书评

暂无评论

Oriented Active Shape models

引用

IEEE TRANSACTIONS ON MEDICAL IMAGING 2009年第4期28卷 571-584页

作者： Liu, Jiamin Udupa, Jayaram K. Univ Penn Dept Radiol Med Image Proc Grp Philadelphia PA 19104 USA NIH Virtual Endoscopy & Comp Aided Diag Lab Dept Radiol & Imaging Sci Bethesda MD 20892 USA

Active shape models (ASM) are widely employed for recognizing anatomic structures and for delineating them in medical images. In this paper, a novel strategy called oriented active shape models (OASM) is presented in an attempt to overcome the following five limitations of ASM: 1) lower delineation accuracy, 2) the requirement of a large number of landmarks, 3) sensitivity to search range, 4) sensitivity to initialization, and 5) inability to fully exploit the specific information present in the given image to be segmented. OASM effectively combines the rich statistical shape information embodied in ASM with the boundary orientedness property and the globally optimal delineation capability of the live wire methodology of boundary segmentation. The latter characteristics allow live wire to effectively separate an object boundary from other nonobject boundaries with similar properties especially when they come very close in the image domain. The approach leads to a two-level dynamic programming method, wherein the first level corresponds to boundary recognition and the second level corresponds to boundary delineation, and to an effective automatic initialization method. The method outputs a globally optimal boundary that agrees with the shape model if the recognition step is successful in bringing the model close to the boundary in the image. Extensive evaluation experiments have been conducted by utilizing 40 image (magnetic resonance and computed tomography) data sets in each of five different application areas for segmenting breast, liver, bones of the foot, and cervical vertebrae of the spine. Comparisons are made between OASM and ASM based on precision, accuracy, and efficiency of segmentation. Accuracy is assessed using both region-based false positive and false negative measures and boundary-based distance measures. The results indicate the following: 1) The accuracy of segmentation via OASM is considerably better than that of ASM;2) The number of landmarks can

关键词： Active shape models (ASMs) dynamic programming image-based segmentation live wire model-based segmentation

来源：评论

学校读者我要写书评

暂无评论

A graph-based object description for information retrieval in digital image and video libraries

引用

JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 2002年第4期13卷 425-459页

作者： Özer, IB Wolf, W Akansu, AN Princeton Univ Dept Elect Engn Princeton NJ 08544 USA New Jersey Inst Technol Dept Elect & Comp Engn Newark NJ 07102 USA

This work focuses on the search of a sample object (car) in video sequences and images based on shape similarity. We form anew description for cars, using relational graphs in order to annotate the images where the object of interest (OOI) is present. Query by text can be performed afterward to extract images of OOI from an automatically preprocessed database. The performance of the general retrieval systems is not satisfactory due to the gap between high level concepts and low level features. In this study we successfully fulfill this gap by using the graph-based description scheme which provides an efficient way to obtain high-level semantics from low-level features. We investigate the full potential of the shape matching method based on relational graph of objects with respect to its accuracy, efficiency, and scalability. We use hierarchical segmentation that increases the accuracy of the detection of the object in the transformed and occluded images. Many shape-based similarity retrieval methods perform well if the initial segmentation is adequate;however, in most cases segmentation without a priori information or user interference yields unsuccessful object extraction results. Compared to other methods, the major advantage of the proposed method is its ability to create semantic segments automatically from the combination of low level edge- or region-based segments using model-based segmentation. It is shown that a graph-based description of the complex objects with model-based segmentation is a powerful scheme for automatic annotation of images and videos. (C) 2002 Elsevier Science (USA).

关键词： object retrieval graph matching hierarchical car model model-based segmentation

来源：评论

学校读者我要写书评

暂无评论

Integrating prior shape models into level-set approaches

引用

PATTERN RECOGNITION LETTERS 2004年第6期25卷 631-639页

作者： Pardo, XM Leborán, V Dosil, R Univ Santiago de Compostela Fac Fis Dept Elect & Computac Santiago De Compostela 15706 Spain

To incorporate prior shape information into a deformable model either local or global shape modeling must be carried out. Local shape modeling involves manual interaction to accumulate information on the shape variability of any object. It depends on the existence of homologous points, or landmarks, that must be unambiguously and consistently located in different specimens. Global shape modeling does not require the existence of landmarks. Global properties can be characterized using only a few parameters, and tend to be much more stable than local properties. In this work we propose a new approach that combines the benefits of local and global shape modeling in the field of level-set approaches. The method starts with local shape parameterization, which eases user interaction. Then, the shape is converted into an implicit representation which exploits the stability and compactness of global shape parameters. (C) 2004 Elsevier B.V. All rights reserved.

关键词： model-based segmentation implicit modeling training level-set approach

来源：评论

学校读者我要写书评

暂无评论

Efficient Shape Priors for Spline-based Snakes

引用

IEEE TRANSACTIONS ON IMAGE PROCESSING 2015年第11期24卷 3915-3926页

作者： Delgado-Gonzalo, Ricard Schmitter, Daniel Uhlmann, Virginie Unser, Michael Ecole Polytech Fed Lausanne Biomed Imaging Grp CH-1015 Lausanne Switzerland

Parametric active contours are an attractive approach for image segmentation, thanks to their computational efficiency. They are driven by application-dependent energies that reflect the prior knowledge on the object to be segmented. We propose an energy involving shape priors acting in a regularization-like manner. Thereby, the shape of the snake is orthogonally projected onto the space that spans the affine transformations of a given shape prior. The formulation of the curves is continuous, which provides computational benefits when compared with landmark-based (discrete) methods. We show that this approach improves the robustness and quality of spline-based segmentation algorithms, while its computational overhead is negligible. An interactive and ready-to-use implementation of the proposed algorithm is available and was successfully tested on real data in order to segment Drosophila flies and yeast cells in microscopic images.

关键词： Active contours model-based segmentation parametric snake deformable template B-spline shape space

来源：评论

学校读者我要写书评

暂无评论

A hierarchical human detection system in (un)compressed domains

引用

IEEE TRANSACTIONS ON MULTIMEDIA 2002年第2期4卷 283-300页

作者： Ozer, IB Wolf, WH Princeton Univ Dept Elect Engn Princeton NJ 08544 USA

With the rapid growth of multimedia information in forms of digital image and video libraries, there is an increasing need for intelligent database management tools with an efficient information retrieval system. For this purpose, we propose a hierarchical retrieval system where shape, color and motion characteristics of human body are captured in compressed and uncompressed domains. The proposed retrieval method provides human detection and activity recognition at different resolution levels from low complexity to low false rates and connects low level features to high level semantics by developing relational object and activity presentations. The available information of standard video compression algorithms are used in order to reduce the amount of time and storage needed for the information retrieval. The principal component analysis is used for activity recognition using MPEG motion vectors and results are presented for walking, kicking, and running to demonstrate that the classification among activities is clearly visible. For low resolution and monochrome images it is demonstrated that the structural information of human silhouettes can be captured from AC-DCT coefficients. The system performance is tested on 40 images that contain a total of 126 nonoccluded frontal poses and the algorithm can detect 101 of them correctly. The finest details in the images and video sequences are obtained from the uncompressed domain via model based segmentation and graph matching for an in depth analysis of human bodies. The detection rate for human body parts is 70.27% for images and sequences including human body regions at different resolutions and with different postures.

关键词： activity recognition eigenspace representation human detection image and video databases JPEG model-based segmentation MPEG relational graph matching

来源：评论

学校读者我要写书评

暂无评论

Pictorial recognition of objects employing affine invariance in the frequency domain

引用

IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 1998年第6期20卷 604-618页

作者： Ben-Arie, J Wang, ZQ Univ Illinois Dept EECS Chicago IL 60607 USA

This paper describes an efficient approach to pose invariant pictorial object recognition employing spectral signatures of image patches that correspond to object surfaces which are roughly planar. based on Singular Value Decomposition (SVD), the affine transform is decomposed into slant, tilt, swing, scale, and 2D translation. Unlike previous log-polar representations which were not invariant to slant (i.e., foreshortening only in one direction), our log-log sampling configuration in the frequency domain yields complete affine invariance. The images are preprocessed by a novel model-based segmentation scheme that detects and segments objects that are affine-similar to members of a model set of basic geometric shapes. The segmented objects are then recognized by their signatures using multidimensional indexing in a pictorial dataset represented in the frequency domain. Experimental results with a dataset of 26 models show 100 percent recognition rates in a wide range of 3D pose parameters and imaging degradations: 0-360 degrees swing and tilt, 0-82 degrees of slant (more than 1:7 foreshortening), more than three octaves in scale change, window-limited translation, high noise levels (0 dB), and significantly reduced resolution (1:5).

关键词： affine invariant recognition model-based segmentation affine invariant spectral signatures (AISS) multidimensional indexing Gabor kernels

来源：评论

学校读者我要写书评

暂无评论

3D Geometry-based Quantification of Colocalizations in Multichannel 3D Microscopy Images of Human Soft Tissue Tumors

引用

IEEE TRANSACTIONS ON MEDICAL IMAGING 2010年第8期29卷 1474-1484页

作者： Woerz, Stefan Sander, Petra Pfannmoeller, Martin Rieker, Ralf J. Joos, Stefan Mechtersheimer, Gunhild Boukamp, Petra Lichter, Peter Rohr, Karl Heidelberg Univ Biomed Comp Vis Grp Dept Bioinformat & Funct Genom IPMBBIOQUANT D-69120 Heidelberg Germany DKFZ Heidelberg D-69120 Heidelberg Germany German Canc Res Ctr Dept Mol Genet Heidelberg Germany Univ Hosp Dept Pathol D-69120 Heidelberg Germany Med Univ Innsbruck Inst Pathol A-6020 Innsbruck Austria German Canc Res Ctr Dept Genet Skin Carcinogenesis D-69120 Heidelberg Germany

We introduce a new model-based approach for automatic quantification of colocalizations in multichannel 3D microscopy images. The approach uses different 3D parametric intensity models in conjunction with a model fitting scheme to localize and quantify subcellular structures with high accuracy. The central idea is to determine colocalizations between different channels based on the estimated geometry of the subcellular structures as well as to differentiate between different types of colocalizations. A statistical analysis was performed to assess the significance of the determined colocalizations. This approach was used to successfully analyze about 500 three-channel 3D microscopy images of human soft tissue tumors and controls.

关键词： Geometric colocalizations model-based segmentation parametric intensity models Telomeres and Promyelocytic leukemia (PML) bodies

来源：评论

学校读者我要写书评

暂无评论

Patient-specific models for lung nodule detection and surveillance in CT images

引用

IEEE TRANSACTIONS ON MEDICAL IMAGING 2001年第12期20卷 1242-1250页

作者： Brown, MS McNitt-Gray, MF Goldin, JG Suh, RD Sayre, JW Aberle, DR Univ Calif Los Angeles Dept Radiol Sci Los Angeles CA 90095 USA

The purpose of this work is to develop patient-specific models for automatically detecting lung nodules in computed tomography (CT) images. It is motivated by significant developments in CT scanner technology and the burden that lung cancer screening and surveillance imposes on radiologists. We propose a new method that uses a patient's baseline image data to assist in the segmentation of subsequent images so that changes in size and/or shape of nodules can be measured automatically. The system uses a generic, a priori model to detect candidate nodules on the baseline scan of a previously unseen patient. A user then confirms or rejects nodule candidates to establish baseline results. For analysis of follow-up scans of that particular patient, a patient-specific model is derived from these baseline results. This model describes expected features (location, volume and shape) of previously segmented nodules so that the system can relocalize them automatically on follow-up. On the baseline scans of 17 subjects, a radiologist identified a total of 36 nodules, of which 31 (86%) were detected automatically by the system with an average of 11 false positives (FPs) per case. In follow-up scans 27 of the 31 nodules were still present and, using patient-specific models, 22 (81%) were correctly relocalized by the system. The system automatically detected 16 out of a possible 20 (80%) of new nodules on follow-up scans with ten FPs per case.

关键词： computed tomography model-based segmentation nodule detection patient-specific model

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：