arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2006.06911cs.CVcs.LGeess.IV
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Iterate & Cluster:迭代式半监督动作识别

Iterate & Cluster: Iterative Semi-Supervised Action Recognition

University of Washington(华盛顿大学)

Jingyuan Li, Eli Shlizerman

摘要:

我们提出了一种新的主动半监督基于特征的动作识别系统。给定运动过程中跟踪的特征的时间序列,我们的系统将序列聚类为动作。我们的系统是基于编码器-解码器无监督的方法,通过自回归任务,通过自组织其潜在的表示来执行聚类。这些方法在人类动作识别基准上进行了测试,优于基于非特征的无监督方法,并达到了与基于特征的监督方法相当的准确性。然而,这样的方法依赖于将序列与动作相关联的K最近邻(KNN),并且没有注释数据的一般特征将对应于可以进一步增强的近似聚类。我们的系统提出了一种迭代的半监督方法来解决这一挑战,并积极学习集群和动作的关联。该方法利用潜空间嵌入和聚类的无监督编码器-解码器,以指导选择序列进行注释,在每次迭代。每次迭代,选择的目的是提高动作识别的准确性,同时选择少量的序列进行注释。我们测试的方法对人类的动作识别基准,假设只有我们的方法选择的注释是可用的,并在实验室实验中记录的鼠标运动视频。我们表明,我们的系统可以提高识别性能,只有一小部分的注释。该系统可以用作交互式注释工具,以指导各种对象和动作的“野外”视频的标记工作,以实现鲁棒的识别。

英文摘要:

We propose a novel system for active semi-supervised feature-based action recognition. Given time sequences of features tracked during movements our system clusters the sequences into actions. Our system is based on encoder-decoder unsupervised methods shown to perform clustering by self-organization of their latent representation through the auto-regression task. These methods were tested on human action recognition benchmarks and outperformed non-feature based unsupervised methods and achieved comparable accuracy to skeleton-based supervised methods. However, such methods rely on K-Nearest Neighbours (KNN) associating sequences to actions, and general features with no annotated data would correspond to approximate clusters which could be further enhanced. Our system proposes an iterative semi-supervised method to address this challenge and to actively learn the association of clusters and actions. The method utilizes latent space embedding and clustering of the unsupervised encoder-decoder to guide the selection of sequences to be annotated in each iteration. Each iteration, the selection aims to enhance action recognition accuracy while choosing a small number of sequences for annotation. We test the approach on human skeleton-based action recognition benchmarks assuming that only annotations chosen by our method are available and on mouse movements videos recorded in lab experiments. We show that our system can boost recognition performance with only a small percentage of annotations. The system can be used as an interactive annotation tool to guide labeling efforts for 'in the wild' videos of various objects and actions to reach robust recognition.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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