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A search engine for 3d models
 ACM Transactions on Graphics
, 2003
"... As the number of 3D models available on the Web grows, there is an increasing need for a search engine to help people find them. Unfortunately, traditional textbased search techniques are not always effective for 3D data. In this paper, we investigate new shapebased search methods. The key challen ..."
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Cited by 300 (22 self)
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As the number of 3D models available on the Web grows, there is an increasing need for a search engine to help people find them. Unfortunately, traditional textbased search techniques are not always effective for 3D data. In this paper, we investigate new shapebased search methods. The key challenges are to develop query methods simple enough for novice users and matching algorithms robust enough to work for arbitrary polygonal models. We present a webbased search engine system that supports queries based on 3D sketches, 2D sketches, 3D
Shape Distributions
 ACM Transactions on Graphics
, 2002
"... this paper, we propose and analyze a method for computing shape signatures for arbitrary (possibly degenerate) 3D polygonal models. The key idea is to represent the signature of an object as a shape distribution sampled from a shape function measuring global geometric properties of an object. The pr ..."
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Cited by 274 (2 self)
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this paper, we propose and analyze a method for computing shape signatures for arbitrary (possibly degenerate) 3D polygonal models. The key idea is to represent the signature of an object as a shape distribution sampled from a shape function measuring global geometric properties of an object. The primary motivation for this approach is to reduce the shape matching problem to the comparison of probability distributions, which is simpler than traditional shape matching methods that require pose registration, feature correspondence, or model fitting
Matching 3D Models with Shape Distributions
"... Measuring the similarity between 3D shapes is a fundamental problem, with applications in computer vision, molecular biology, computer graphics, and a variety of other fields. A challenging aspect of this problem is to find a suitable shape signature that can be constructed and compared quickly, whi ..."
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Cited by 212 (7 self)
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Measuring the similarity between 3D shapes is a fundamental problem, with applications in computer vision, molecular biology, computer graphics, and a variety of other fields. A challenging aspect of this problem is to find a suitable shape signature that can be constructed and compared quickly, while still discriminating between similar and dissimilar shapes. In this paper, we propose and analyze a method for computing shape signatures for arbitrary (possibly degenerate) 3D polygonal models. The key idea is to represent the signature of an object as a shape distribution sampled from a shape function measuring global geometric properties of an object. The primary motivation for this approach is to reduce the shape matching problem to the comparison of probability distributions, which is a simpler problem than the comparison of 3D surfaces by traditional shape matching methods that require pose registration, feature correspondence, or model fitting. We find that the dissimilarities be...
A Reflective Symmetry Descriptor for 3D Models
 ALGORITHMICA
, 2004
"... Computing reflective symmetries of 2D and 3D shapes is a classical problem in computer vision and computational geometry. Most prior work has focused on finding the main axes of symmetry, or determining that none exists. In this paper we introduce a new reflective symmetry descriptor that represent ..."
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Cited by 71 (8 self)
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Computing reflective symmetries of 2D and 3D shapes is a classical problem in computer vision and computational geometry. Most prior work has focused on finding the main axes of symmetry, or determining that none exists. In this paper we introduce a new reflective symmetry descriptor that represents a measure of reflective symmetry for an arbitrary 3D model for all planes through the model’s center of mass (even if they are not planes of symmetry). The main benefits of this new shape descriptor are that it is defined over a canonical parameterization (the sphere) and describes global properties of a 3D shape. We show how to obtain a voxel grid from arbitrary 3D shapes and, using Fourier methods, we present an algorithm that computes the symmetry descriptor in O(N 4 log N) time for an N × N × N voxel grid and computes a multiresolution approximation in O(N 3 log N) time. In our initial experiments, we have found that the symmetry descriptor is insensitive to noise and stable under point sampling. We have also found that it performs well in shape matching tasks, providing a measure of shape similarity that is orthogonal to existing methods.
Efficiency of Simple Shape Descriptors
 In Aspects of Visual Form
, 1997
"... this paper is to emphasize ..."
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An Adaptive Texture and Shape Based Defect Classification
 In Proc. International Conf. on Pattern Recognition
, 1998
"... In this paper classification of surface defects is considered. The classification system consists of several classifiers whose outputs are combined in order to produce the final classification. The selforganizing maps (SOMs) are used as classifiers. Each SOM is taught unsupervised with examples of ..."
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Cited by 13 (9 self)
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In this paper classification of surface defects is considered. The classification system consists of several classifiers whose outputs are combined in order to produce the final classification. The selforganizing maps (SOMs) are used as classifiers. Each SOM is taught unsupervised with examples of defects. Classification is based on the internal structure and the shape characteristics of defects. Texture features from the cooccurrence matrix and the gray level histogram are used to describe the internal structure. The set of simple shape descriptors is used for shape characterization The results of experiments with base paper defects are encouraging. 1. Introduction Recognition of objects is one of the basic tasks in computer vision applications. The goal of object recognition is to find a description which contains sufficient information to distinguish between different target objects. Recognition is usually based on gray levels or colors and shape characteristics [14, 12] of targe...
Shape Recognition of Irregular Objects
 Intelligent Robots and Computer Vision XV: Algorithms, Techniques, Active Vision, and Materials Handling, Proc. SPIE 2904
, 1996
"... A new approach to object recognition is proposed. The main concern is on irregular objects which are hard to recognize even for a human. The recognition is based on the contour of an object. The contour is obtained with morphological operators and described with a Freeman chain code. The chain code ..."
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Cited by 11 (1 self)
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A new approach to object recognition is proposed. The main concern is on irregular objects which are hard to recognize even for a human. The recognition is based on the contour of an object. The contour is obtained with morphological operators and described with a Freeman chain code. The chain code histogram (CCH) is calculated from the chain code of the contour of an object. For an eightconnected chain code an eight dimensional histogram (CCH), which shows the probability of each direction, is obtained. The CCH is a translation and scale invariant shape measure. The CCH gives only an approximation of the object's shape so that similar objects can be grouped together. The discriminatory power of the CCH is demonstrated on machineprinted text and on true irregular objects. In both cases it is noted that similar objects (according to the shape of the contour) are grouped together. The results of experiments are good. It has been shown that similar objects are grouped together with the ...
A new shape matching measure for nonlinear distorted object recognition
 In: Proceedings of the VIIth Digital Image Computing: Techniques and Applications
, 2003
"... Abstract. In this paper, we present a new approach for handwritten character and digit recognitions based on shape descriptor and the Hausdorff Context. We start at finding the corresponding points between two shapes by using a modified shape context. We then use these correspondences as key geomet ..."
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Cited by 3 (1 self)
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Abstract. In this paper, we present a new approach for handwritten character and digit recognitions based on shape descriptor and the Hausdorff Context. We start at finding the corresponding points between two shapes by using a modified shape context. We then use these correspondences as key geometric points for shape alignment with the Thin Plate Spline (TPS) model. After the transformation has been applied completely, the distance between two shapes is computed by a new distance measure, the Hausdorff Context. We achieve a very high recognition rate of 98.7 % on 268 images. 1
Comparison of Combined Shape Descriptors for Irregular Objects
 In Proceedings of the Eight British Machine Vision Conference (Vol
, 1997
"... This paper focuses on recognition powers and computational efforts of three different shape coding techniques, namely the chain code histogram (CCH), the pairwise geometric histogram (PGH), and the combination of simple shape descriptors, for characterization of irregular objects. In recognizing ..."
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This paper focuses on recognition powers and computational efforts of three different shape coding techniques, namely the chain code histogram (CCH), the pairwise geometric histogram (PGH), and the combination of simple shape descriptors, for characterization of irregular objects. In recognizing irregular objects the essential task is to design efficient measures based on relatively small prior knowledge on geometrical constraints of possible target objects. Three rather different approaches are evaluated and discussed by the means of the selforganizing map (SOM). A database retrieval problem is also assumed to further test their discriminatory powers. As a case study, natural irregular objects have been used. Grouping of these objects based on their visual similarity is the main topic in this paper. The combination of simple shape descriptors is shown to have good recognition capabilities and low computation costs.
SHAPEBASED 3D MODEL RETRIEVAL SYSTEM BASED ON ELEVATION DESCRIPTOR
"... Recently, with the construction of digital libraries, the management of the large multimedia databases becomes an ..."
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Recently, with the construction of digital libraries, the management of the large multimedia databases becomes an