Multilayer real-time video image stabilization

Abstract

In many camera-based robotics applications, stabilizing video images in real-time is often critical for successful performance. In particular vision-based navigation, localization and tracking tasks cannot be performed reliably when landmarks are blurry, poorly focused or disappear from the camera view due to strong vibrations. Thus a reliable video image stabilization system would be invaluable for these applications. This paper presents a real-time video image stabilization system (VISS) primarily developed for aerial robots. Its unique architecture combines four independent stabilization layers. Layer 1 detects vibrations via an inertial measurement unit (IMU) and performs external counter-movements with a motorized gimbal. Layer 2 damps vibrations by using mechanical devices. The internal optical image stabilization of the camera represents Layer 3, while Layer 4 filters remaining vibrations using software. VISS is low-cost and robust. It has been implemented on a ¿Photoship One¿ gimbal, using GUMBOT hardware for processing Sparkfun-IMU data (Layer 1). Lord Mount vibration isolators damp vibrations (Layer 2). Video images of Panasonic's Lumix DMCTZ5 camera are optically stabilized with Panasonic's ¿Mega O.I.S.¿ technique (Layer 3) and digitally stabilized with ¿Deshaker¿ software (Layer 4). VISS significantly improved the stability of shaky video images in a series of experiments.