Critically Sampled Third Octave Filter Banks
Scott Levine · 1996
This paper introduces the design of a critically sampled, third octave filter bank. Filter design methods are shown for the octave band filter bank and the third octave sections. In addition, the trade-offs in the design are explained among frequency selectivity, regularity, complexity and memory. 1 Introduction The front end of most current audio data compression algorithms use some sort of time-frequency representation to transform the time domain signal to some other domain more closely matched to the human ear. One accepted model is often called the critical band model, which shows how signals psychoacoustically mask one another, as long as they are within a critical band [Zwicker, 1990]. A close approximation to the critical bands of hearing is a third octave filter bank, which is designed in this paper. Thus, if a signal were bandlimited within a critical band, and then quantized, the resultant quantization noise would remain within the band and would be perceptually masked by t...