基于运动对比度增强的人群运动分割方法

Motion Contrast Enhancement-based Crowd Motion Segmentation Method

公共场所监控视频中的人群运动状态复杂多变,很难通过检测或者跟踪每个个体来实现整个人群运动状态的分析,将人群分割成运动状态基本一致的区域成了了解和分析人群运动状态的有效途径。有监督的人群运动分割方法需要提供数据标注代价极高的像素级的训练集,因此无监督的聚类方法成为了更有前途的人群运动分割方法。然而,由于描述人群运动的局部特征通常是逐渐变化的,导致基于聚类的无监督方法需要针对不同的人群场景选择不同的参数,这很难适应各种不同的应用场景。为此,文中提出了一种基于运动对比度增强的人群运动分割方法。该方法是一种无监督模型,首先根据运动场中运动和噪声的分布特点增强不同运动状态之间的对比度,然后结合自适应阈值分割算法和标记符分水岭算法来提取每个运动状态基本一致的区域,避免了无监督聚类方法参数难以恰当选择的难题。在获得人群运动分割结果的基础上,文中提出了一种能量模型用于描述人群运动状态的稳定性。该能量模型通过推演出整个人群运动状态的变化过程来实现对异常人群运动状态的提前预警。在不同类型的复杂人群运动状态的场景中进行人群运动分割的实验,实验结果验证了基于运动对比度增强的人群运动分割方法的有效性和分割的准确性,以及所提能量模型的有效性。

In surveillance videos of public places,the movement states of the crowds are various and complex,and it is difficult to analyze the movement state of the whole crowd through detecting or segmenting every individual.Therefore,it is an effective way to understand and analyze the movement state of the crowd by dividing the crowd into areas with basically the same movement state.Supervised crowd motion segmentation methods require pixel-level training sets with high labeling costs,and thus unsupervised clustering methods are more promising for crowd motion segmentation.However,since the local features describing crowd movements usually change gradually,leading to the unsupervised methods based on clustering algorithm need to choose different parameters for different crowd scenarios,it is difficult to adapt to a variety of different application scenarios.To this end,this paper proposes a motion contrast improvement-based crowd motion segmentation method.The method is an unsupervised model that first enhances the contrast of different motion states based on the distribution law of movement and noise in the motion field,and then combines the adaptive threshold segmentation algorithm and the marker watershed algorithm to extract the essentially consistent region for each motion state,avoiding the difficulty of parameter selection for unsupervised clustering methods.Based on the results of crowd motion segmentation,this paper presents an energy model to describe the stability of crowd movement.The energy model can enable early warning of abnormal crowd motion state by deducing the change process of the whole crowd motion state.Experiments are conducted on crowd motion segmentation in different types of complex crowd motion state scenes.Experimental results verify the effectiveness and segmentation accuracy of the motion contrast enhancement-based crowd motion segmentation method and the validity of the proposed energy model.