# Image Processing and QR Code Application Method for Construction Safety Management
## 1 Introduction  
In the construction industry, serious safety and fatal accidents are commonly measured high, regardless of the distinction between developing and advanced countries [1]. Researchers and practitioners related to the construction industry are making a lot of effort to solve this problem. However, there is still a long way to go to zero accidents/injuries [2]. Even though the devices and technologies for construction safety management are constantly developing, the construction field's accident rate is still high. According to data released by the U.S. Department of Labor, fatal occupational injuries by primary and secondary source of injury for all fatal injuries in the manufacturing sector (i.e., natural resources and mining, construction, manufacturing) in 2018 was the highest in the construction industry at 49.05% [3].  
Stakeholders in construction projects have different levels of awareness of risks and different levels of understanding of safety according to their experiences and perceptions [4]. In addition, it is difficult to organize a systematic management process because the organizational composition continuously changes and new participants are generated according to the project schedule and stage [5, 6]. This structural limitation of the construction project is a factor that lowers the learning efficiency for the project participants' safety. Continuous safety training is essential to ensure that project participants who are newly organized by project and schedule follow the project's standards and rules for safety management. Moreover, even if safety training has been completed, a system should be established in which the safety manager can check in real-time whether the subject of management complies with the safety-related regulations to manage unsafe safety consciousness and safety behavior of workers. The ideal form of direct safety management for constructionby managers is that enough managers can check all workers scattered throughout the construction site. To satisfy this condition, the site's scale increases the more safety managers must be employed. However, the biggest problems with these actions are (1) large amounts of economic expenditures irrespective of the project production cost and (2) whether it is possible to establish that they have sufficient knowledge for safety management and capabilities regardless of their safety career. Besides, recent studies pointed out that the existing management methods for construction safety do not sufficiently reflect potential risk factors occurring in real-time at the site [7,8]. Researchers argue that the current method should be changed to a bottom-up management method to solve these problems. This method can quickly transfer information generated on-site to headquarters and the person in charge of management and help start an appropriate response process and prepare alternatives [9,10].  
In this paper, the methodology that identifies workers as individuals and estimates the location of workers, and updates their historical data, is presented. The proposed method can be applied to all sites where surveillance cameras are installed and can be applied to all cameras simultaneously. Accordingly, the method can be developed as a prototype of an automatic safety information management system for construction. The system can record workers' safety-related history information without additional devices (e.g., sensors, transmitters, wearing equipment, control systems, etc.) and can be developed as a management system for personalized safety in the future. The case study analyzes the practical application of the methodology.