 Indeed, multifractal signals generally obey a "scale invariance" property that yields power-law behaviours for multiresolution quantities, depending on their scale formula_12.Depending on the object under study, these multiresolution quantities, denoted by formula_13, can be local averages in boxes of size formula_12, gradients over distance formula_12, wavelet coefficients at scale formula_12, etc.For multifractal objects, one usually observes a global power-law scaling of the form