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歧视性的时空行为从弱标记的视频学习

Learning discriminative space-time actions from weakly labelled videos
课程网址: http://videolectures.net/bmvc2012_sapienza_labelled_videos/  
主讲教师: Michael Sapienza
开课单位: 牛津布鲁克斯大学
开课时间: 2012-10-09
课程语种: 英语
中文简介:
当前最先进的动作分类方法从动作展开的整个视频剪辑中提取特征表示,然而该表示可以包括在多个动作类之间共享的不相关的场景上下文和动作。例如,可以在行走时执行挥动动作,但是如果步行运动和场景上下文出现在其他动作类别中,则它们不应被包括在挥动动作分类器中。在这项工作中,我们提出了一个行动分类框架,由于难以手动标记大量视频数据集,因此在弱监督环境中学习更多的判别行动子体积。学习的模型用于同时对视频剪辑进行分类并将动作本地化到给定的时空子体积。每个子体积在多实例学习框架中被转换为bag-offeatures(BoF)实例,而该实例又用于学习其类成员资格。我们定量地证明,即使使用单个固定子体积,我们提出的算法的分类性能优于大多数性能测量的最先进的BoF基线,并且在最具挑战性的情况下显示出时空行动定位的前景。视频数据集。
课程简介: Current state-of-the-art action classification methods extract feature representations from the entire video clip in which the action unfolds, however this representation may include irrelevant scene context and movements which are shared amongst multiple action classes. For example, a waving action may be performed whilst walking, however if the walking movement and scene context appear in other action classes, then they should not be included in a waving movement classifier. In this work, we propose an action classification framework in which more discriminative action subvolumes are learned in a weakly supervised setting, owing to the difficulty of manually labelling massive video datasets. The learned models are used to simultaneously classify video clips and to localise actions to a given space-time subvolume. Each subvolume is cast as a bag-offeatures (BoF) instance in a multiple-instance-learning framework, which in turn is used to learn its class membership. We demonstrate quantitatively that even with single fixedsized subvolumes, the classification performance of our proposed algorithm is superior to the state-of-the-art BoF baseline on the majority of performance measures, and shows promise for space-time action localisation on the most challenging video datasets.
关 键 词: 情景语境; 运动; 视频剪辑
课程来源: 视频讲座网
最后编审: 2020-09-26:yumf
阅读次数: 47