  Speckle patterns are used in a broad range of applications including
microscopy, imaging, and light-matter interactions. Tailoring speckles'
statistics can dramatically enhance their performance in applications. We
present an experimental technique for customizing the spatio-spectral speckled
intensity statistics of optical pulses at the output of a complex medium (a
disordered multimode fiber) by controlling the spatial profile of the input
light. We demonstrate that it is possible to create ensembles of independent
speckle patterns with arbitrary statistics at a single wavelength,
simultaneously at decorrelated wavelengths, and even tailored statistics across
an entire pulse spectrum.
