Self-calibration of a PTZ Camera Using New LMI Constraints

In this paper, we propose a very reliable and flexible method for self-calibrating rotating and zooming cameras - generally referred to as PTZ (Pan-Tilt-Zoom) cameras. The proposed method employs a Linear Matrix Inequality (LMI) resolution approach and allows extra tunable constraints on the intrinsic parameters to be taken into account during the process of estimating these parameters. Furthermore, the considered constraints are simultaneously enforced in all views rather than in a single reference view. The results of our experiments show that the proposed approach allows for significant improvement in terms of accuracy and robustness when compared against state of the art methods.

Tracking Moving Objects With a Catadioptric Sensor Using Particle Filter

International audience; Visual tracking in video sequences is a widely developed topic in computer vision applications. However, the emergence of panoramic vision using catadioptric sensors has created the need for new approaches in order to track an object in this type of images. Indeed the non-linear resolution and the geometric distortions due to the insertion of the mirror, make tracking in catadioptric images a very challenging task. This paper describes particle filter for tracking moving object over time using a catadioptric sensor. In this work different problems due to the specificities of the catadioptric systems such as geometry are considered. The obtained results demonstrate an…

Control of a PTZ Camera in a Hybrid Vision System

Visual tracking with omnidirectional cameras: an efficient approach

International audience; An effective technique for applying visual tracking algorithms to omni- directional image sequences is presented. The method is based on a spherical image representation which allows taking into account the distortions and nonlinear resolution of omnidirectional images. Experimental results show that both deterministic and probabilistic tracking methods can effectively be adapted in order to robustly track an object with an omnidirectional camera.

Structure from motion using a hybrid stereo-vision system

International audience; This paper is dedicated to robotic navigation using an original hybrid-vision setup combining the advantages offered by two different types of camera. This couple of cameras is composed of one perspective camera associated with one fisheye camera. This kind of configuration , is also known under the name of foveated vision system since it is inspired by the human vision system and allows both a wide field of view and a detail front view of the scene. Here, we propose a generic and robust approach for SFM, which is compatible with a very broad spectrum of multi-camera vision systems, suitable for perspective and om-nidirectional cameras, with or without overlapping fi…