The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Josep Lladós - One of the best experts on this subject based on the ideXlab platform.
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a Syntactic Approach based on distortion tolerant adjacency grammars and a spatial directed parser to interpret sketched diagrams
Pattern Recognition, 2010Co-Authors: Josep Lladós, Gemma Sánchez, Joaquim JorgeAbstract:This paper presents a Syntactic Approach based on Adjacency Grammars (AG) for sketch diagram modeling and understanding. Diagrams are a combination of graphical symbols arranged according to a set of spatial rules defined by a visual language. AG describe visual shapes by productions defined in terms of terminal and non-terminal symbols (graphical primitives and subshapes), and a set functions describing the spatial arrangements between symbols. Our Approach to sketch diagram understanding provides three main contributions. First, since AG are linear grammars, there is a need to define shapes and relations inherently bidimensional using a sequential formalism. Second, our parsing Approach uses an indexing structure based on a spatial tessellation. This serves to reduce the search space when finding candidates to produce a valid reduction. This allows order-free parsing of 2D visual sentences while keeping combinatorial explosion in check. Third, working with sketches requires a distortion model to cope with the natural variations of hand drawn strokes. To this end we extended the basic grammar with a distortion measure modeled on the allowable variation on spatial constraints associated with grammar productions. Finally, the paper reports on an experimental framework an interactive system for sketch analysis. User tests performed on two real scenarios show that our Approach is usable in interactive settings.
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A Syntactic Approach based on distortion-tolerant Adjacency Grammars and a spatial-directed parser to interpret sketched diagrams
Pattern Recognition, 2010Co-Authors: Jordi Mas, Josep Lladós, G. Sánchez, J.a.p. JorgeAbstract:This paper presents a Syntactic Approach based on Adjacency Grammars (AG) for sketch diagram modeling and understanding. Diagrams are a combination of graphical symbols arranged according to a set of spatial rules defined by a visual language. AG describe visual shapes by productions defined in terms of terminal and non-terminal symbols (graphical primitives and subshapes), and a set functions describing the spatial arrangements between symbols. Our Approach to sketch diagram understanding provides three main contributions. First, since AG are linear grammars, there is a need to define shapes and relations inherently bidimensional using a sequential formalism. Second, our parsing Approach uses an indexing structure based on a spatial tessellation. This serves to reduce the search space when finding candidates to produce a valid reduction. This allows order-free parsing of 2D visual sentences while keeping combinatorial explosion in check. Third, working with sketches requires a distortion model to cope with the natural variations of hand drawn strokes. To this end we extended the basic grammar with a distortion measure modeled on the allowable variation on spatial constraints associated with grammar productions. Finally, the paper reports on an experimental framework an interactive system for sketch analysis. User tests performed on two real scenarios show that our Approach is usable in interactive settings. © 2010 Elsevier Ltd. All rights reserved.
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GREC - SSP: sketching slide presentations, a Syntactic Approach
Graphics Recognition. Achievements Challenges and Evolution, 2009Co-Authors: Gemma Sánchez, Josep LladósAbstract:The design of a slide presentation is a creative process. In this process first, humans visualize in their minds what they want to explain. Then, they have to be able to represent this knowledge in an understandable way. There exists a lot of commercial software that allows to create our own slide presentations but the creativity of the user is rather limited. In this article we present an application that allows the user to create and visualize a slide presentation from a sketch. A slide may be seen as a graphical document or a diagram where its elements are placed in a particular spatial arrangement. To describe and recognize slides a Syntactic Approach is proposed. This Approach is based on an Adjacency Grammar and a parsing methodology to cope with this kind of grammars. The experimental evaluation shows the performance of our methodology from a qualitative and a quantitative point of view. Six different slides containing different number of symbols, from 4 to 7, have been given to the users and they have drawn them without restrictions in the order of the elements. The quantitative results give an idea on how suitable is our methodology to describe and recognize the different elements in a slide.
Joaquim Jorge - One of the best experts on this subject based on the ideXlab platform.
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a Syntactic Approach based on distortion tolerant adjacency grammars and a spatial directed parser to interpret sketched diagrams
Pattern Recognition, 2010Co-Authors: Josep Lladós, Gemma Sánchez, Joaquim JorgeAbstract:This paper presents a Syntactic Approach based on Adjacency Grammars (AG) for sketch diagram modeling and understanding. Diagrams are a combination of graphical symbols arranged according to a set of spatial rules defined by a visual language. AG describe visual shapes by productions defined in terms of terminal and non-terminal symbols (graphical primitives and subshapes), and a set functions describing the spatial arrangements between symbols. Our Approach to sketch diagram understanding provides three main contributions. First, since AG are linear grammars, there is a need to define shapes and relations inherently bidimensional using a sequential formalism. Second, our parsing Approach uses an indexing structure based on a spatial tessellation. This serves to reduce the search space when finding candidates to produce a valid reduction. This allows order-free parsing of 2D visual sentences while keeping combinatorial explosion in check. Third, working with sketches requires a distortion model to cope with the natural variations of hand drawn strokes. To this end we extended the basic grammar with a distortion measure modeled on the allowable variation on spatial constraints associated with grammar productions. Finally, the paper reports on an experimental framework an interactive system for sketch analysis. User tests performed on two real scenarios show that our Approach is usable in interactive settings.
J.a.p. Jorge - One of the best experts on this subject based on the ideXlab platform.
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A Syntactic Approach based on distortion-tolerant Adjacency Grammars and a spatial-directed parser to interpret sketched diagrams
Pattern Recognition, 2010Co-Authors: Jordi Mas, Josep Lladós, G. Sánchez, J.a.p. JorgeAbstract:This paper presents a Syntactic Approach based on Adjacency Grammars (AG) for sketch diagram modeling and understanding. Diagrams are a combination of graphical symbols arranged according to a set of spatial rules defined by a visual language. AG describe visual shapes by productions defined in terms of terminal and non-terminal symbols (graphical primitives and subshapes), and a set functions describing the spatial arrangements between symbols. Our Approach to sketch diagram understanding provides three main contributions. First, since AG are linear grammars, there is a need to define shapes and relations inherently bidimensional using a sequential formalism. Second, our parsing Approach uses an indexing structure based on a spatial tessellation. This serves to reduce the search space when finding candidates to produce a valid reduction. This allows order-free parsing of 2D visual sentences while keeping combinatorial explosion in check. Third, working with sketches requires a distortion model to cope with the natural variations of hand drawn strokes. To this end we extended the basic grammar with a distortion measure modeled on the allowable variation on spatial constraints associated with grammar productions. Finally, the paper reports on an experimental framework an interactive system for sketch analysis. User tests performed on two real scenarios show that our Approach is usable in interactive settings. © 2010 Elsevier Ltd. All rights reserved.
Jordi Mas - One of the best experts on this subject based on the ideXlab platform.
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A Syntactic Approach based on distortion-tolerant Adjacency Grammars and a spatial-directed parser to interpret sketched diagrams
Pattern Recognition, 2010Co-Authors: Jordi Mas, Josep Lladós, G. Sánchez, J.a.p. JorgeAbstract:This paper presents a Syntactic Approach based on Adjacency Grammars (AG) for sketch diagram modeling and understanding. Diagrams are a combination of graphical symbols arranged according to a set of spatial rules defined by a visual language. AG describe visual shapes by productions defined in terms of terminal and non-terminal symbols (graphical primitives and subshapes), and a set functions describing the spatial arrangements between symbols. Our Approach to sketch diagram understanding provides three main contributions. First, since AG are linear grammars, there is a need to define shapes and relations inherently bidimensional using a sequential formalism. Second, our parsing Approach uses an indexing structure based on a spatial tessellation. This serves to reduce the search space when finding candidates to produce a valid reduction. This allows order-free parsing of 2D visual sentences while keeping combinatorial explosion in check. Third, working with sketches requires a distortion model to cope with the natural variations of hand drawn strokes. To this end we extended the basic grammar with a distortion measure modeled on the allowable variation on spatial constraints associated with grammar productions. Finally, the paper reports on an experimental framework an interactive system for sketch analysis. User tests performed on two real scenarios show that our Approach is usable in interactive settings. © 2010 Elsevier Ltd. All rights reserved.
Guangzheng Yang - One of the best experts on this subject based on the ideXlab platform.
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on the knowledge based pattern recognition using Syntactic Approach
Pattern Recognition, 1991Co-Authors: Guangzheng YangAbstract:Abstract This paper presents a method for building the knowledge-based pattern recognition system using Syntactic Approach. Two important problems are discussed: the knowledge representation by means of grammar production and the search strategy. A production of context-free grammar [ A → β ] can represent knowledge [IF β THEN A ]. This conclusion is just contrary to the conventional viewpoint. For the heuristic search a depth-first parsing algorithm—the ED algorithm—is presented. On this basis the author has proposed a new type of knowledge-based pattern recognition system, in which the attributed grammar is used to represent knowledge and the Earley algorithm or the ED algorithm is used to search the conclusion. Two examples of application are given.
