Methods Of Measurement The Three-Dimensional Wind Waves Spectra, Based On The Processing Of Video Images Of The Sea Surface
This work addresses a domain-specific challenge in oceanography by improving wave measurement accuracy, but it is incremental as it builds on existing optical methods.
The authors tackled the problem of converting indirect optical measurements of sea surface waves into absolute wave levels by proposing a method for measuring 3D power spectral density and wave profiles using video images, with experimental results that generally align with theoretical expectations.
Optical instruments for measuring surface-wave characteristics provide a better spatial and temporal resolution than other methods, but they face difficulties while converting the results of indirect measurements into absolute levels of the waves. We have solved this problem to some extent. In this paper, we propose an optical method for measuring the 3D power spectral density of the surface waves and spatio-temporal samples of the wave profiles. The method involves, first, synchronous recording of the brightness field over a patch of a rough surface and measurement of surface oscillations at one or more points and, second, filtering of the spatial image spectrum. Filter parameters are chosen to maximize the correlation of the surface oscillations recovered and measured at one or two points. In addition to the measurement procedure, the paper provides experimental results of measuring multidimensional spectra of roughness, which generally agree with theoretical expectations and the results of other authors.