Abstract

The main objective of this study is to track some moving objects in an infrared image sequence and retrieve their temperature field. We first implement some tracking techniques commonly used in the computer vision field. Unfortunately, trackers of this kind are not directly well suited for thermal frame monitoring, since heat diffusion yields both light level changes and three-dimensional effects. The proposed algorithms are thus adapted and then tested for velocity measurements in real experiments involving the stochastic moving of spheres on an oscillating plate. Circle Hough transforms, digital image correlation, and mathematical morphology tools are considered and their efficiency is evaluated. The labeling of the moving objects is then implemented in order to retrieve and discriminate the thermal field of each target within a lagrangian approach. Heat transfer between the moving object and the surrounding medium can then be characterized: In the case presented herein, the convective heat transfer coefficient is estimated.