Estimating Interpersonal Distance and Crowd Density with a Single-Edge Camera

Alem Fitwi,Han Sun,Robert Harrod,Yu Chen

doi:10.3390/computers10110143

Abstract

For public safety and physical security, currently more than a billion closed-circuit television (CCTV) cameras are in use around the world. Proliferation of artificial intelligence (AI) and machine/deep learning (M/DL) technologies have gained significant applications including crowd surveillance. The state-of-the-art distance and area estimation algorithms either need multiple cameras or a reference object as a ground truth. It is an open question to obtain an estimation using a single camera without a scale reference. In this paper, we propose a novel solution called E-SEC, which estimates interpersonal distance between a pair of dynamic human objects, area occupied by a dynamic crowd, and density using a single edge camera. The E-SEC framework comprises edge CCTV cameras responsible for capturing a crowd on video frames leveraging a customized YOLOv3 model for human detection. E-SEC contributes an interpersonal distance estimation algorithm vital for monitoring the social distancing of a crowd, and an area estimation algorithm for dynamically determining an area occupied by a crowd with changing size and position. A unified output module generates the crowd size, interpersonal distances, social distancing violations, area, and density per every frame. Experimental results validate the accuracy and efficiency of E-SEC with a range of different video datasets.

Highlights

The closed circuit television (CCTV) is a closed-loop television system where the CCTV pictures or video streams are only available to those connected directly into the loop unlike the broadcast television system which is available to anyone with an appropriate receiver
In order to reproduce results generated in this work, videos must be recorded with any type of camera positioned at a point at least 3 m higher from the ground with its pixel per foot (PPF) set to at least 40
This paper proposes a unified E-SEC framework for the the estimation of interpersonal distances and area occupied by a crowd caught on a single camera

Summary

Introduction

The closed circuit television (CCTV) is a closed-loop television system where the CCTV pictures or video streams are only available to those connected directly into the loop unlike the broadcast television system which is available to anyone with an appropriate receiver. It creates a scenario where both premises and the people within them are constantly surveyed This provides the security teams and property managers a tighter control over accesses to properties and facilities [1,2,3]. With the main goals of ensuring physical security and public safety, there are more than a billion CCTV cameras in use around the globe enabling the law enforcers and security personnel to collect huge amount of information about individuals and follow their activities live [4,5,6,7,8] It helps to identify law breaking individuals and deters crimes. They could be employed to contain contagious diseases, like COVID-19, by providing data useful for faster interpersonal gap and crowd density determinations and alerting people to maintain the minimum required social distance between them

Results

Discussion

Conclusion