Robust Feedback Zoom Tracking for Digital Video Surveillance

Sensors

Tengyue Zou²  Xiaoqi Tang²  Bao Song¹  Jin Wang² 

[1] National NC System Engineering Research Center, Huazhong University of Science and Technology, Wuhan 430074, China;

关键词: zoom tracking;    video surveillance;    focus value;    focus control;    PID feedback;   

DOI  :  10.3390/s120608073

来源: mdpi

【 摘 要 】

Zoom tracking is an important function in video surveillance, particularly in traffic management and security monitoring. It involves keeping an object of interest in focus during the zoom operation. Zoom tracking is typically achieved by moving the zoom and focus motors in lenses following the so-called “trace curve”, which shows the in-focus motor positions versus the zoom motor positions for a specific object distance. The main task of a zoom tracking approach is to accurately estimate the trace curve for the specified object. Because a proportional integral derivative (PID) controller has historically been considered to be the best controller in the absence of knowledge of the underlying process and its high-quality performance in motor control, in this paper, we propose a novel feedback zoom tracking (FZT) approach based on the geometric trace curve estimation and PID feedback controller. The performance of this approach is compared with existing zoom tracking methods in digital video surveillance. The real-time implementation results obtained on an actual digital video platform indicate that the developed FZT approach not only solves the traditional one-to-many mapping problem without pre-training but also improves the robustness for tracking moving or switching objects which is the key challenge in video surveillance.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.