摘要
现有的自监督表征算法主要关注视频帧之间的短期运动特性,但是帧间动作序列的变化幅度较小,而且单视图数据因语义受限影响深度特征表达能力,视频动作中丰富的多视图信息未被充分利用。为此提出基于跨视图语义一致性的时序对比学习算法,自监督学习RGB帧和光流场两种数据中蕴含的动作时序变化特性,主要思路为:设计局部时序对比学习方法,采用不同正负样本划分策略,挖掘同一实例不重叠片段之间的时序相关性和判别可分性,增强细粒度特征表达能力;研究全局对比学习方法,通过跨视图语义协同训练来增加正样本,学习多实例不同视图的语义一致性,提高模型的泛化能力。通过两个下游任务对模型效果进行评估,在UCF101和HMDB51数据集的实验结果表明,所提方法在动作识别和视频检索任务上,较前沿主流方法平均提升了2~3.5个百分点。
The existing self-supervised representation algorithms mainly focus on the short-term motion characteristics between video frames,but the variation range of the action sequence between frames is small,and the depth feature expression ability of single-view data is affected due to semantic limitations,so the rich multi-view information in video actions is not fully utilized.Therefore,a temporal contrast learning algorithm based on cross-view semantic consistency is proposed to self-supervised learn the action temporal variation characteristics embedded in both RGB frames and optical flow field data.The main ideas are as follows:to design a local temporal contrast learning method,adopt different posi-tive and negative sample division strategies to explore the temporal correlation and discriminative differentiability between non-overlapping segments of the same instance,and enhance the fine-grained feature expression capability;to study the global contrast learning method to increase the positive samples by cross-view semantic co-training,learn the semantic consistency of different views of multiple instances,and improve the generalization ability of the model.The model per-formance is evaluated through two downstream tasks,and the experimental results on UCF101 and HMDB51 datasets show that the proposed method improves on average 2~3.5 percentage points over cutting-edge mainstream methods on action recognition and video retrieval tasks.
作者
王露露
徐增敏
张雪莲
蒙儒省
卢涛
WANG Lulu;XU Zengmin;ZHANG Xuelian;MENG Ruxing;LU Tao(Guangxi Colleges and Universities Key Laboratory of Data Analysis and Computation,School of Mathematics and Computing Science,Guilin University of Electronic Technology,Guilin,Guangxi 541004,China;Center for Applied Mathematics of Guangxi(GUET),Guilin,Guangxi 541004,China;Anview.ai,Guilin,Guangxi 541010,China;Hubei Key Laboratory of Intelligent Robot,School of Computer Science and Engineering,Wuhan Institute of Technology,Wuhan 430205,China)
出处
《计算机工程与应用》
CSCD
北大核心
2024年第18期158-166,共9页
Computer Engineering and Applications
基金
广西自然科学基金(2024GXNSFAA010493)
国家自然科学基金(61862015,62072350)
广西科技基地和人才专项(AD23023002,AD21220114)
广西重点研发计划项目(AB17195025)。
关键词
自监督学习
视频表征学习
时序对比学习
局部对比学习
跨视图协同
self-supervised learning
video representation learning
temporal contrastive learning
local contrastive learning
cross-view co-training