Predicting congregational and crowd spread-out flow using YOLOv4 and DeepSORT
Nahla Aljojo1, Hanin Ardah2, Ahmed Alamri3
1Department of Information Systems & Technology, College of Computer sciences & Engineering, University of Jeddah, Jeddah, Saudi Arabia. nmaljojo@uj.edu.sa.
Scientific Reports
|March 18, 2026
Summary
This study uses YOLOv4 and DeepSORT for crowd management during religious events like Hajj. The system accurately tracks individuals, aiding in safety and population flow analysis for large gatherings.
Area of Science:
- Computer Vision
- Artificial Intelligence
- Public Safety
Background:
- Urban expansion necessitates advanced crowd control and population management strategies.
- Major events require structured organization for participant safety and emergency mitigation.
- Analyzing congregational and dispersed crowd flow dynamics presents significant challenges.
Purpose of the Study:
- To develop and evaluate a predictive system for managing large crowds during religious events.
- To address challenges in predicting and analyzing crowd flow dynamics.
- To enhance safety and efficiency in managing mass gatherings.
Main Methods:
- A case study analyzing religious events (Hajj and Umrah) in Saudi Arabia with 1.5-4 million participants.
- Implementation of two distinct algorithms: YOLOv4 for object detection and DeepSORT for object tracking.
- Training the YOLOv4 and DeepSORT models on a dataset of pilgrim images captured during Hajj 2019.
Main Results:
- YOLOv4 achieved 95.30% accuracy, 94.80% precision, 95.60% recall, and 95.20% F1-score.
- DeepSORT achieved 91.50% accuracy and 92.30% recall.
- The system successfully identified and tracked individuals, counted entries/exits, and classified crowd density (low, medium, high).
Conclusions:
- The developed system effectively manages complex crowd dynamics during major religious gatherings.
- The YOLOv4 and DeepSORT approach demonstrates the potential to revolutionize crowd management strategies.
- Accurate individual identification and flow analysis are achievable even in crowded, dynamic environments.
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