Topological features for monitoring human activities at distance

In this paper, a topological approach for monitoring human activities is presented. This approach makes possible to protect the person’s privacy hiding details that are not essential for processing a security alarm. First, a stack of human silhouettes, extracted by background subtraction and thresho...

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Detalles Bibliográficos
Autores: Lamar León, Javier, Alonso Baryolo, Raúl, García Reyes, Edel, González Díaz, Rocío
Tipo de recurso: capítulo de libro
Fecha de publicación:2014
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/30925
Acceso en línea:http://hdl.handle.net/11441/30925
https://doi.org/10.1007/978-3-319-13323-2_4
Access Level:acceso abierto
Palabra clave:Gait-based recognition
Topology
Persistent homology
Gender classification
Carrying bag detection
Action recognition
Descripción
Sumario:In this paper, a topological approach for monitoring human activities is presented. This approach makes possible to protect the person’s privacy hiding details that are not essential for processing a security alarm. First, a stack of human silhouettes, extracted by background subtraction and thresholding, are glued through their gravity centers, forming a 3D digital binary image I. Secondly, different orders of the simplices are applied on a simplicial complex obtained from I, which capture relations among the parts of the human body when walking. Finally, a topological signature is extracted from the persistence diagrams according to each order. The measure cosine is used to give a similarity value between topological signatures. In this way, the powerful topological tool known as persistent homology is novelty adapted to deal with gender classification, person identification, carrying bag detection and simple action recognition. Four experiments show the strength of the topological feature used; three of they use the CASIA-B database, and the fourth use the KTH database to present the results in the case of simple actions recognition. In the first experiment the named topological signature is evaluated, obtaining 98.8% (lateral view) of correct classification rates for gender identification. In the second one are shown results for person identification, obtaining an average of 98.5%. In the third one the result obtained is 93.8% for carrying bag detection. And in the last experiment the results were 97.7% walking and 97.5% running, which were the actions took from the KTH database.