  The multifractal nature of solar photospheric magnetic structures are studied
using the 2D wavelet transform modulus maxima (WTMM) method. This relies on
computing partition functions from the wavelet transform skeleton defined by
the WTMM method. This skeleton provides an adaptive space-scale partition of
the fractal distribution under study, from which one can extract the
multifractal singularity spectrum. We describe the implementation of a
multiscale image processing segmentation procedure based on the partitioning of
the WT skeleton which allows the disentangling of the information concerning
the multifractal properties of active regions from the surrounding quiet-Sun
field. The quiet Sun exhibits a average H\"older exponent $\sim -0.75$, with
observed multifractal properties due to the supergranular structure. On the
other hand, active region multifractal spectra exhibit an average H\"older
exponent $\sim 0.38$ similar to those found when studying experimental data
from turbulent flows.
