arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2004.04981cs.CV
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3D CNN中的时空融合:概率观点

Spatiotemporal Fusion in 3D CNNs: A Probabilistic View

Microsoft Research Asia(微软亚洲研究院);University of Science and Technology of China(中国科学技术大学)

Yizhou Zhou, Xiaoyan Sun, Chong Luo, Zheng-Jun Zha, Wenjun Zeng

摘要:

尽管在静态图像识别方面取得了成功,但用于时空信号任务(例如视频中的人类动作识别)的深度神经网络在过去几年中仍然存在低效率和低效率。最近,人类专家投入了更多的精力来分析3D卷积神经网络(3D CNN)中不同组件的重要性,以设计更强大的时空学习骨干。其中,时空融合是其中的一个关键。它控制在推理过程中如何在每一层提取空间和时间信号。以前的尝试通常从ad-hoc设计开始,这些设计经验性地结合某些卷积,然后根据训练相应网络获得的性能得出结论。这些方法只支持对有限数量的融合策略进行网络级分析。在本文中,我们建议将时空融合策略转换成一个概率空间,这使我们能够执行网络级的各种融合策略的评估,而不必单独进行训练。此外,我们还可以获得细粒度的数值信息,如层级偏好的时空融合的概率空间内。我们的方法大大提高了时空融合分析的效率。基于概率空间,我们进一步生成新的融合策略,在四个著名的动作识别数据集上实现了最先进的性能。

英文摘要:

Despite the success in still image recognition, deep neural networks for spatiotemporal signal tasks (such as human action recognition in videos) still suffers from low efficacy and inefficiency over the past years. Recently, human experts have put more efforts into analyzing the importance of different components in 3D convolutional neural networks (3D CNNs) to design more powerful spatiotemporal learning backbones. Among many others, spatiotemporal fusion is one of the essentials. It controls how spatial and temporal signals are extracted at each layer during inference. Previous attempts usually start by ad-hoc designs that empirically combine certain convolutions and then draw conclusions based on the performance obtained by training the corresponding networks. These methods only support network-level analysis on limited number of fusion strategies. In this paper, we propose to convert the spatiotemporal fusion strategies into a probability space, which allows us to perform network-level evaluations of various fusion strategies without having to train them separately. Besides, we can also obtain fine-grained numerical information such as layer-level preference on spatiotemporal fusion within the probability space. Our approach greatly boosts the efficiency of analyzing spatiotemporal fusion. Based on the probability space, we further generate new fusion strategies which achieve the state-of-the-art performance on four well-known action recognition datasets.

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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