Figure 3: Wavelet transform of a 512x512, 8 bit per pixel, gray-scale image showing a fingerprint (taken from Bradley et al. 1993). In the upper left, the original data; upper right, its reconstruction after keeping only the most intense 1.5% of the coefficients. The lower left shows the wavelet coefficients, where small-scales are over-exposed for clarity. In the lower right, the scale-wise and direction-wise distribution of the strongest 1.5% of the coefficients kept in the reconstruction is shown. Scales j and directions q are separated by solid lines.

Figure 4: Wavelet transform of a slice through a forced, 128^3 modes DNS of homogeneous isotropic turbulence at Re_lambda=45. On the left, the original data. The image on the right shows the intensity of the wavelet coefficients.

Figure 5: Isosurfaces of vorticity magnitude at |omega|=4 omega' of homogeneous-isotropic flow at Re_lambda=45. The linear dimension of the visualized sub-domain corresponds to 225 Kolmogorov lengths. On the left, the full field; on the right, the field which is reconstructed after high-pass filtering in wavelet space according to the threshold given in the text where 99.2% of the coefficients are discarded