Wavelets and wavelet packets to analyse, filter and compress two-dimensional turbulent flows

This article presents the continuous wavelet transform and its property. It is applied to: analyze two-dimensional turbulent flows, compute their local energy spectrum, (scalogram) and their intermittendy factor, and to extract the coherent structures which emerge and nonlinearly interact during their flow evolution. The orthogonal wavelet packet transform presented in the second part and applied to compress two-dmiensional turbulent flows. It also show how the orthogonal wavelet packet transform can be used to compress two-dimensional turbulent flows for different compression rates. This article has been published in 1993 by Hawaï University Press in a book entitled `Probability Concepts in Physical Oceanography', edited by Peter Müller (page131 to 159)