TY - CONF AU - Pau Riba AU - Josep Llados AU - Alicia Fornes AU - Anjan Dutta A2 - GbRPR ED - C.-L.Liu ED - B.Luo ED - W.G.Kropatsch ED - J.Cheng PY - 2015// TI - Large-scale Graph Indexing using Binary Embeddings of Node Contexts T2 - LNCS BT - 10th IAPR-TC15 Workshop on Graph-based Representations in Pattern Recognition SP - 208 EP - 217 VL - 9069 PB - Springer International Publishing KW - Graph matching KW - Graph indexing KW - Application in document analysis KW - Word spotting KW - Binary embedding N2 - Graph-based representations are experiencing a growing usage in visual recognition and retrieval due to their representational power in front of classical appearance-based representations in terms of feature vectors. Retrieving a query graph from a large dataset of graphs has the drawback of the high computational complexity required to compare the query and the target graphs. The most important property for a large-scale retrieval is the search time complexity to be sub-linear in the number of database examples. In this paper we propose a fast indexation formalism for graph retrieval. A binary embedding is defined as hashing keys for graph nodes. Given a database of labeled graphs, graph nodes are complemented with vectors of attributes representing their local context. Hence, each attribute counts the length of a walk of order k originated in a vertex with label l. Each attribute vector is converted to a binary code applying a binary-valued hash function. Therefore, graph retrieval is formulated in terms of finding target graphs in the database whose nodes have a small Hamming distance from the query nodes, easily computed with bitwise logical operators. As an application example, we validate the performance of the proposed methods in a handwritten word spotting scenario in images of historical documents. SN - 0302-9743 SN - 978-3-319-18223-0 UR - http://www.springer.com/us/book/9783319182230 L1 - http://refbase.cvc.uab.es/files/RLF2015a.pdf UR - http://dx.doi.org/10.1007/978-3-319-18224-7_21 N1 - DAG; 600.061; 602.006; 600.077 ID - Pau Riba2015 ER -