On the Potential of Information Theoretic Indicators for the Detection of Image Vibrations and for Image Registration on JET

In Tokamaks, the use of cameras as diagnostics has increased remarkably in the last years. One of the main technical difficulties, in interpreting the data of camera-based diagnostics, is the presence of movements and vibrations of the field of view, consequence of various plasma phenomena, and modes of operation. Typically, these movements results in rigid transformations of the frames. In this paper, various information theoretic indicators (correlations, entropies, and mutual information) are described and their potential to detect the vibrations and to register images is investigated. The indicators are applied to a representative set of videos collected by Joint European Torus wide-angle infrared camera. For movement detection, the Tsallis entropy is the indicator with the best performance, providing a success rates in excess of 86% and an almost equal number of false and missed detections. Its application to image registration looks also very promising.