Variable time-frequency tiling using block transforms

It is well known that block transforms have fixed resolution in the time-frequency plane and lack flexibility in dealing with signals possessing a time-varying spectrum. We introduce new orthonormal transforms which are constructed from any block transform yet have variable time-frequency-localizability feature and fast computing capability. A framework is created for constructing time localizable block transform (TLBT) and an algorithm is developed to achieve a desired time-frequency tiling pattern.