FEATURE LINE EXTRACTION ON MESHES THROUGH VERTEX MARKING AND 2D TOPOLOGICAL OPERATORS

2011 ◽  
Vol 11 (04) ◽  
pp. 531-548 ◽  
Author(s):  
DIMITRI KUDELSKI ◽  
SOPHIE VISEUR ◽  
GIOVANNI SCROFANI ◽  
JEAN-LUC MARI

Classical approaches of feature line detection rely on curvature derivatives. They generally suffer from a common problem: the connectivity is hard to obtain and it is impossible to generate intersections between feature lines. This article presents a method to extract feature lines on 3D meshes. In order to sort out the recurrent issues of traditional approaches, we propose a novel algorithm based on two ideas. First, all the mesh vertices are marked according to the curvature values: a binary map with candidate regions is then constructed. The second idea is to isolate each candidate region and transform it into a line. To achieve this, we parameterize the region into its 2D regular representation. We then perform a skeletonization to obtain lines with high connectivity. By applying the inverse parameterization, the feature lines are mapped back onto the 3D mesh. In the end, we extract perceptual salient parts and above all connected feature lines. In order to evaluate and validate our algorithm, we compare our method to classical ones and apply our technique to a geological context.

2012 ◽  
Vol 263-266 ◽  
pp. 2049-2053
Author(s):  
Ying Gao ◽  
Rui Zhao Wang ◽  
Ping Xin Ji

To get complete and accurate triangular mesh model in reverse engineering, the hole-filling operation is indispensable. This paper presents a new feature preserving hole-filling algorithm based on the feature line extraction. Firstly, the hole and its neighborhood were obtained. Then, the feature lines in the hole region were extracted which were used to divided the hole to several single surface holes. To each hole, triangulation and subdivision were performed. Finally, the new added vertices in the hole were moved to the underlying surface which was approximated by the hole neighborhood. The experimental results demonstrate that our mesh hole-filling algorithm can effectively recover the original shape of the hole.


Author(s):  
Wenhao Wang ◽  
Mingxin Jiang ◽  
Xiaobing Chen ◽  
Li Hua ◽  
Shangbing Gao

In the original compression tracking algorithm, the size of the tracking box is fixed. There should be better tracking results for scale-invariant objects, but worse tracking results for scale-variant objects. To overcome this defect, a scale-adaptive compressive tracking (CT) algorithm is proposed. First of all, the imbalance of the gray and texture features in the original CT algorithm is balanced by the multi-feature method, which makes the algorithm more robust. Then, searching different candidate regions by using the method of multi-scale search along with feature normalization makes the features extracted from different scales comparable. Finally, the candidate region with the maximum discriminate degree is selected as the object region. Thus, the tracking-box size is adaptive. The experimental results show that when the object scale changes, the improving CT algorithm has higher accuracy and robustness than the original CT algorithm.


2019 ◽  
Author(s):  
Martin Denk ◽  
◽  
Kristin Paetzold ◽  
Klemens Rother ◽  

Author(s):  
Jianying Yuan ◽  
Jiajia Liu

Substation patrol robots (SIR) play an increasingly important role in ensuring the safe operation of substations. The robust and precise position estimating of the instruments to be inspected on the images are a prerequisite for accurately detecting the target states or obtaining the target readings under all-weather environment. In order to achieve high location accuracy of instrument, this study proposed an improved kernelized correlation filter (KCF) algorithm for achieving robust instrument location on images for SPR. Firstly, multiple templates are selected for training KCF classifier parameters. Then, reliable SURF matching-point determination method is designed, and the regions including reliable matching points are selected as the candidate regions, so that the searching range is narrowed. Finally, for KCF response surface of each candidate region, Single-Peak Constraint (SPC) is designed for locating target and reducing mismatching rate. Furthermore, experiments are performed for validating the effectiveness of the proposed algorithm, in which four instruments mainly including lightning arrester monitor and transformer thermometer are selected. The experimental results show that the proposed method has higher accuracy of target localization than traditional SURF-based position estimating method.


2019 ◽  
Vol 27 (5) ◽  
pp. 1218-1228
Author(s):  
陈华伟 CHEN Hua-wei ◽  
袁小翠 YUAN Xiao-cui ◽  
吴禄慎 WU Lu-chen ◽  
王晓辉 WANG Xiao-hui

2010 ◽  
Vol 2010 ◽  
pp. 1-4 ◽  
Author(s):  
Nadia Bayou ◽  
Ahlem Belhadj ◽  
Hussein Daoud ◽  
Sylvain Briault ◽  
M. Bechir Helayem ◽  
...  

A high incidence of de novo chromosomal aberrations in a population of persons with autism suggests a causal relationship between certain chromosomal aberrations and the occurrence of autism. A previous study on a Tunisian boy carrying a t(7;16) translocation identified the 7p22.1 as a positional candidate region for autism on chromosome 7. The characterization of the chromosomal breakpoints helped us to identify new candidate regions on chromosome 16p11.2 which contain no known genes and the other one on 7p22.1 containing a portion of genes (NP 976327.1, RBAK, Q6NUR6 also called RNF216L and MMD2). We proposed Q6NUR6 (RNF216L) as a candidate gene for autism due to its vicinity to the translocation breakpoint on the chromosome derivative 7. Q6NUR6 is predicted to be an E3ubiquitin-ligase. Quantitative PCR demonstrates that Q6NUR6 gene has an ubiquitous expression and that it is strongly expressed in fetal and adult brain. The Q6NUR6 expression is increased in the patient blood cells in comparison to controls. This is the first report of Q6NUR6 gene (E3 ubiquitin ligase TRIAD3 EC 6.3.2) increasing blood levels in a patient with autism. It's probably caused by a position effect involving this gene and modifying its expression.


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