Applies descriptor to every cuboid of every clip of every set. INPUTS DATASETS - array of structs, should have the fields: .ncilps - N: number of clips .cuboids - length N cell vector of sets of cuboids cubdesc - cuboid descriptor OUTPUTS DATASETS - array of structs, will have additional fields: .desc - length N cell vector of cuboid descriptors See also FEATURESSM, IMAGEDESC, IMAGEDESC_GENERATE