Abstract: A signal processing apparatus for use in data communications systems where the transmitted signal is subject to the effects of short duration interference, such as impulse noise, or for use in data recording systems where recorded data is subject to the effects of imperfections in the recording media, wherein a coded transformation is performed on an input signal to the apparatus in accordance with a selected time distribution and selected multi-level, integer related weighting functions to produce a coded signal. A decoder can be used to reversibly transform such signal so as to substantially reproduce the input signal in a manner such that the effects of such noise and recording imperfections are minimized.