Active contour algorithm: An attractive tool for snow avalanche analysis

Abstract

Image processing is increasingly used for the study of snow avalanches in order to prevent them. The study of the dynamics of snow avalanches has produced many numerical models. The difficulty of the measurement of parameters provided by these models has prevented their validation by comparison with those of real phenomena. Image processing is a first approach for these validations. This study aims to determine and analyse the velocity of the envelope in case of powder-snow avalanches. This work is based on active snake methods. In this paper, we present a new algorithm of active contours in order to analyse the front of motion of snow avalanches. The algorithm uses an energy-minimising curve. The model developed takes avalanche characteristics and the nature of the images into account. The algorithm gives good results and we obtain a sequence of avalanche contours.