一个新的无监督视频异常检测框架,基于光流重建和删除预测
Heqing Huang1, Bing Zhao2, Fei Gao1,3
1School of Electronic and Information Engineering, Beihang University, Beijing 100190, China.
Sensors (Basel, Switzerland)
|July 11, 2023
概括
本研究引入了一种新的无监督学习框架,用于使用Cloze测试策略检测视频异常 (VAD). 该方法通过对象级运动和外观编码来准确识别不寻常活动,从而增强智能城市监控.
科学领域:
- 计算机视觉 计算机视觉
- 人工智能的人工智能
- 机器学习 机器学习
背景情况:
- 传统的视频异常检测 (VAD) 方法很难利用上下文信息来准确地感知异常.
- 基于重建和基于预测的方法在智能城市监控中很常见,但有限.
研究的目的:
- 为视频异常检测 (VAD) 开发一种新的无监督学习框架.
- 使用Cloze测试策略,在对象层面有效编码运动和外观信息.
- 为了提高智能城市监控中异常检测的准确性和可靠性.
主要方法:
- 一个光流内存网络与跳过连接被设计用于正常视频活动的重建.
- 作为基本处理单元,使用时空立方体 (STC),删除补丁以形成不完整事件 (IE) 进行重建.
- 使用条件自动编码器和基于生成对抗网络 (GAN) 的培训方法来预测被删除的补丁并提高VAD性能.
主要成果:
- 拟议的方法在基准数据集上获得了高的AUROC分数:UCSD Ped2的97.7%,CUHK大道的89.7%,上海科技的75.8%.
- 该框架有效地捕捉了光流和STC之间的高对应性,从而实现可靠的异常检测.
- 区分预测的擦除光流和视频提高了VAD结果的可靠性.
结论:
- 这种新的无监督学习框架,灵感来自NLP的Cloze测试,显著提高了视频异常检测.
- 该方法通过预测被删除的补丁来重建不完整事件的能力,提高了对上下文信息的利用.
- 这种方法为智能城市监控应用中的异常检测提供了更可靠的解决方案.
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