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A discriminative cnn video representation for event detection
- In CVPR
, 2015
"... In this paper, we propose a discriminative video rep-resentation for event detection over a large scale video dataset when only limited hardware resources are avail-able. The focus of this paper is to effectively leverage deep Convolutional Neural Networks (CNNs) to advance event detection, where on ..."
Abstract
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Cited by 3 (1 self)
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In this paper, we propose a discriminative video rep-resentation for event detection over a large scale video dataset when only limited hardware resources are avail-able. The focus of this paper is to effectively leverage deep Convolutional Neural Networks (CNNs) to advance event detection, where only frame level static descriptors can be extracted by the existing CNN toolkit. This paper makes two contributions to the inference of CNN video representa-tion. First, while average pooling and max pooling have long been the standard approaches to aggregating frame level static features, we show that performance can be sig-nificantly improved by taking advantage of an appropriate encoding method. Second, we propose using a set of latent concept descriptors as the frame descriptor, which enriches visual information while keeping it computationally afford-able. The integration of the two contributions results in a new state-of-the-art performance in event detection over the largest video datasets. Compared to improved Dense Trajectories, which has been recognized as the best video representation for event detection, our new representation improves the Mean Average Precision (mAP) from 27.6% to 36.8 % for the TRECVID MEDTest 14 dataset and from 34.0 % to 44.6 % for the TRECVID MEDTest 13 dataset. 1. Introduction and Related
The INRIA-LIM-VocR and AXES submissions for TrecVid 2014 Multimedia Event Detection
, 2015
"... HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte p ..."
Abstract
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Cited by 2 (1 self)
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HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Complex Event Detection using Semantic Saliency and Nearly-Isotonic SVM
"... We aim to detect complex events in long Inter-net videos that may last for hours. A major chal-lenge in this setting is that only a few shots in a long video are relevant to the event of inter-est while others are irrelevant or even misleading. Instead of indifferently pooling the shots, we first de ..."
Abstract
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Cited by 1 (1 self)
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We aim to detect complex events in long Inter-net videos that may last for hours. A major chal-lenge in this setting is that only a few shots in a long video are relevant to the event of inter-est while others are irrelevant or even misleading. Instead of indifferently pooling the shots, we first define a novel notion of semantic saliency that as-sesses the relevance of each shot with the event of interest. We then prioritize the shots accord-ing to their saliency scores since shots that are semantically more salient are expected to con-tribute more to the final event detector. Next, we propose a new isotonic regularizer that is able to exploit the semantic ordering information. The resulting nearly-isotonic SVM classifier exhibits higher discriminative power. Computationally, we develop an efficient implementation using the proximal gradient algorithm, and we prove new, closed-form proximal steps. We conduct extensive experiments on three real-world video datasets and confirm the effectiveness of the pro-posed approach. 1.
Beat-Event Detection in Action Movie Franchises
, 2015
"... HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte p ..."
Abstract
- Add to MetaCart
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HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
