Fire locating method based on the convex hull algorithm using partially blocked surveillance cameras
WANG Guanning1,2,3, CHEN Tao1, MI Wenzhong4, LIANG Xiaoliang5, WANG Rudong1,6
1. Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Gansu Fire and Rescue Department, Lanzhou 730000, China; 3. Anhui Province Key Laboratory of Human Safety, Hefei 230601, China; 4. Hefei Institute for Public Safety Research, Tsinghua University, Hefei 230601, China; 5. Beijing Fire and Rescue Department, Beijing 100035, China; 6. Unit 96963, PLA, Beijing 100192, China
Abstract：Video analyses have become very useful in fire investigations. However, the cause of the fire cannot be easily determined when the surveillance cameras are partially blocked. This study analyzes fire locating methods based on the convex hull algorithm when the surveillance cameras are partially blocked. An oil pan pool fire is used to simulate an indoor fire. The charge-couple device (CCD) camera views are partially blocked with the fire scene videos then collected for analyses. The flame videos are collected and preprocessed before analyzing. Then, a convex hull algorithm is used to calculate the pixel coordinates of the flame center. Finally, the monocular vision principle is used to develop a matrix transformation between the world coordinate system and the imaging plane coordinate system to accurately determine the fire location. Tests show that the monocular visual positioning method based on the convex hull algorithm using partially blocked cameras can accurately locate the fire origin as a powerful tool for fire investigations.
王冠宁, 陈涛, 米文忠, 梁晓良, 王汝栋. 基于凸壳理论的监控摄像头部分遮挡场景下火焰定位方法[J]. 清华大学学报（自然科学版）, 2022, 62(2): 277-284.
WANG Guanning, CHEN Tao, MI Wenzhong, LIANG Xiaoliang, WANG Rudong. Fire locating method based on the convex hull algorithm using partially blocked surveillance cameras. Journal of Tsinghua University(Science and Technology), 2022, 62(2): 277-284.
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