Two Variational Stereo Methods for Space-Time Measurements of Ocean Waves

In recent years, the study of the dynamics of ocean waves via stereo vision systems has focused on investigating sea states with wavelengths in the range of 0.01 m to 1 m. In this work, we present two modern stereo variational approaches, viz. the disparity and graph methods, for the estimation of the ocean surface displacements over larger spatial scales of 10 to 100 m. The disparity method estimates the disparity between images as an intermediate step toward retrieving the depth of the waves with respect to the cameras, and the graph method estimates the ocean surface displacements directly in 3-D space. The pros and cons of both methods are compared and their performance is evaluated using experimental video data collected at an offshore platform in the Black Sea.