An LPC k-parameter software speech synthesizer via dynamic microprogramming a general purpose computer

In a previous paper, it was shown that the presence of a combinatorial shifter in the data paths of a user microprogrammable general purpose computer could be used for fast fixed-point multiplication if a unique microsubroutine was created for each required multiplier. A sixth-order direct form IIR digital filter was implemented via this technique. This work has been extended, so as to produce a tenth-order LPC k-parameter lattice synthesizer software system which executes in about 60% real time. The remaining CPU time may be allocated for k-parameter manipulation, as in synthesis-by-rule aAgorithms, or for unrelated computation. The approach used is novel since it involves dynamic analysis of k-parameters and creation of the microsubroutines required for synthesis during each pitch period. The results suggest that a high speed shifter embedded in an otherwise conventional micromachine architecture is Useful for practical, real-time digital signal processing applications.