  We present a simple scheme to determine the diffusion properties of a thin
slab of strongly scattering material by measuring the speckle contrast
resulting from the transmission of a femtosecond pulse with controlled
bandwidth. In contrast with previous methods, our scheme does not require time
measurements nor interferometry. It is well adapted to the characterization of
samples for pulse shaping, non-linear excitation through scattering media and
biological imaging.
