Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237)最新文献_第2页

Comparing the influence of color spaces and metrics in content-based image retrieval 色彩空间和度量在基于内容的图像检索中的影响比较

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722775

E. Mathias, A. Conci

{"title":"Comparing the influence of color spaces and metrics in content-based image retrieval","authors":"E. Mathias, A. Conci","doi":"10.1109/SIBGRA.1998.722775","DOIUrl":"https://doi.org/10.1109/SIBGRA.1998.722775","url":null,"abstract":"Visual information retrieval systems have been developed from the necessity of searching and recovering data in libraries with million of daily produced digital images. In image retrieval based on their color content, the distance between color histograms defines usually the matching degree. Results of an image querying depend, at least, on the following features: the underlying color space, the number of histogram bins, and the metric used for histogram matching. Several systems have been designed for image retrieval. Comparison among them is not feasible because they use completely different implementation aspects. The purpose of this paper is to evaluate the influence of color spaces and metrics on the performances of recovering by color similarity based on color histograms. A system that performs queries through the Internet and allows one to combine metrics and color spaces is implemented. We design a database with groups of perceptually similar color image, with parameters to measure the performance among combined approaches, and with a user-consult simulator. This leads to a process of establishing the influence of spaces and metrics which evaluate the better combination on retrieval.","PeriodicalId":282177,"journal":{"name":"Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126722123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 36

Visualization of geological prospecting data 地质勘探数据可视化

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722744

K. Basso, C. M. Dal Sasso Freitas

{"title":"Visualization of geological prospecting data","authors":"K. Basso, C. M. Dal Sasso Freitas","doi":"10.1109/SIBGRA.1998.722744","DOIUrl":"https://doi.org/10.1109/SIBGRA.1998.722744","url":null,"abstract":"Oil reservoirs searching is based on several exploratory methods, which produce a large quantity of data that must be interpreted and analyzed by geologists. Graphic systems can help these tasks by providing three-dimensional representations to convey information in a more natural and efficient way to the users. Therefore, they are typical scientific visualization applications. This paper presents results from work on the development of interactive visualization tools for the analysis of geological data obtained from well samples. Since these data are essentially scattered, interpolation techniques are required to the creation of geological models. The system provides a data base management system for storing information used by both interpolation and visualization modules. The modified Shepard interpolation method was implemented and some improvements were made to generate more accurate results in sparsely sampled regions. The visualization module uses the Visualization Toolkit (VTK) to create images showing geological layers as three-dimensional surfaces with attributes mapped to colors and isocontour maps.","PeriodicalId":282177,"journal":{"name":"Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131445293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Comparison of different source localization methods 不同信号源定位方法的比较

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722767

D.C. Fernandez, R. De Peralta Menendez, S. Andino, E.O. Farras

{"title":"Comparison of different source localization methods","authors":"D.C. Fernandez, R. De Peralta Menendez, S. Andino, E.O. Farras","doi":"10.1109/SIBGRA.1998.722767","DOIUrl":"https://doi.org/10.1109/SIBGRA.1998.722767","url":null,"abstract":"The localization of the neural generators of the brain's electromagnetic activity based an electrical or magnetic recordings requires the solution of an ill-posed inverse problem. In its general form, this inverse problem has no unique solution. The only way to deal with this problem, is to restrict the set of possible solutions by using either anatomical or mathematical constraints or a combination of both. On the basis of these restrictions, different reconstructions of the sources of EEG and MEG are possible, each providing a different representation of the electrical processes in the brain. Opposed to the more classical dipole localization methods, inverse procedures that produce distributed estimates of neuronal currents have received increasing attention in the last few years. In this paper, we compare different source localization methods using data from a pathological subject. Among these methods are: (1) spatio-temporal source models (BESA); (2) generalized minimum norm solutions (MNS) and (3) electromagnetic temporal tomography (EMTT). In order to assess their specific performance, each method is compared with the information contained in the CT.","PeriodicalId":282177,"journal":{"name":"Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132634843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Error measures in greedy insertion simplification methods 贪婪插入简化方法中的误差度量

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722736

A. Antunes Montenegro, M. Gattass, P. Cezar Pinto Carvalho

引用次数: 0

An approach to physiologically meaningful distributed inverse solutions to the neuro-electromagnetic inverse problem 神经电磁反问题的一种具有生理意义的分布式反解方法

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722768

E.O. Farras, R. De Peralta Menendez, S. G. González Andino, D.C. Fernandez, E. A. Vázquez

{"title":"An approach to physiologically meaningful distributed inverse solutions to the neuro-electromagnetic inverse problem","authors":"E.O. Farras, R. De Peralta Menendez, S. G. González Andino, D.C. Fernandez, E. A. Vázquez","doi":"10.1109/SIBGRA.1998.722768","DOIUrl":"https://doi.org/10.1109/SIBGRA.1998.722768","url":null,"abstract":"The problem of determining the generators of brain electromagnetic activity has no unique solution. The only way to deal this problem, sometimes denominated \"the problem of the non-uniqueness\", is to restrict the set of possible solutions by using either physiological or mathematical constraints or a combination of both. The main purpose of this work is to propose a method for obtaining a unique distributed solution to the neuro-electromagnetic inverse problem by considering physiological constraints regarding the spatio temporal distribution of the generators. We will focus in discussing distributed inverse solutions (given in terms of the current density vector) which are general enough to include the concentrated inverse solution. Aspects related to the uniqueness of the new inverse solution proposed are discussed that suggest that this solution warrants further development. We consider as the main merit of this proposal the possibility of including new terms extracted from the new developments in neurophysiology.","PeriodicalId":282177,"journal":{"name":"Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132213799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A graph-anisotropic approach to 3-D data segmentation 三维数据分割的图各向异性方法

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722759

R. Chaine, S. Bouakaz, D. Vandorpe

引用次数: 2

Accuracy assessment of a photogrammetric close-range reconstruction system 摄影测量近景重建系统的精度评估

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722732

A. Tommaselli

引用次数: 1

Virtual seismic interpretation 虚拟地震解释

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722741

L. A. Lima, R. Bastos

引用次数: 0

A general specification for scene animation 场景动画的通用规范

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722753

G.S. Lee

引用次数: 7

Density estimation for MR image elastic matching 磁共振图像弹性匹配的密度估计

Proceedings SIBGRAPI'98. International Symposium on Computer Graphics, Image Processing, and Vision (Cat. No.98EX237) Pub Date : 1998-01-20 DOI: 10.1109/SIBGRA.1998.722766

A. Machado, James C. Gee, Mario F. M. Campos

引用次数: 3