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Compressed domain indexing of scalable H.264/SVC streams / Christian Käs in Signal processing. Image communication, Vol. 24 N° 6 (Juillet 2009) 

Public ISBD [article]  in Signal processing. Image communication > Vol. 24 N° 6 (Juillet 2009) . - pp. 484-498 Titre : Compressed domain indexing of scalable H.264/SVC streams Type de document : texte imprimé Auteurs : Christian Käs, Auteur ; Henri Nicolas, Auteur Article en page(s) : pp. 484-498 Note générale : Electronique Langues : Anglais (eng) Mots-clés : H.264/SVC  Trajectory  estimation  Object  distance  estimation  Copy  detection Index. décimale : 621.382 Dispositifs électroniques utilisant les effets des corps solides. Dispositifs semi-conducteurs Résumé : We present methods to efficiently analyze scalable, compressed H.264/scalable video coding (SVC) video streams. Relying solely on information present in the compressed stream, we estimate the global camera motion, perform motion segmentation and use a simple matching process to track moving objects over time. Object energy images are constructed in order to help resolve the problem of object correspondence during the occlusions of multiple objects. To save computing time, we analyze lower spatial layers of the stream and add higher layer information only if necessary. We draw 2-D object trajectories in the view plane of the camera and use the temporal evolution of the objects’ properties to estimate the relative distance to the camera, resulting in a pseudo 3-D representation of the trajectories. Finally, the suitability of the motion parameters to perform video retrieval/copy detection tasks is demonstrated. We therefore form two simple descriptors that are invariant to a series of transformations. DEWEY : 361.382 ISSN : 0923-5965 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235640%23 [...] [article] Compressed domain indexing of scalable H.264/SVC streams [texte imprimé] / Christian Käs, Auteur ; Henri Nicolas, Auteur . - pp. 484-498. Electronique Langues : Anglais (eng) in Signal processing. Image communication > Vol. 24 N° 6 (Juillet 2009) . - pp. 484-498 Mots-clés : H.264/SVC  Trajectory  estimation  Object  distance  estimation  Copy  detection Index. décimale : 621.382 Dispositifs électroniques utilisant les effets des corps solides. Dispositifs semi-conducteurs Résumé : We present methods to efficiently analyze scalable, compressed H.264/scalable video coding (SVC) video streams. Relying solely on information present in the compressed stream, we estimate the global camera motion, perform motion segmentation and use a simple matching process to track moving objects over time. Object energy images are constructed in order to help resolve the problem of object correspondence during the occlusions of multiple objects. To save computing time, we analyze lower spatial layers of the stream and add higher layer information only if necessary. We draw 2-D object trajectories in the view plane of the camera and use the temporal evolution of the objects’ properties to estimate the relative distance to the camera, resulting in a pseudo 3-D representation of the trajectories. Finally, the suitability of the motion parameters to perform video retrieval/copy detection tasks is demonstrated. We therefore form two simple descriptors that are invariant to a series of transformations. DEWEY : 361.382 ISSN : 0923-5965 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235640%23 [...]