On a fast pitch search of CELP type vocoder using decimation technique

Code excited linear prediction (CELP) vocoders exhibit good performance at data rates below 4.8 kbps. The major drawback of CELP type coders is a large amount of computation. In this paper, we propose a new pitch searching method that preserves the quality of the CELP vocoder and reduces computational complexity. The basic idea is to grasp preliminary pitches using major formant for speech signal and perform pitch search only about the preliminary pitches. Applying the proposed method to the CELP vocoder, we can reduce complexity by an average 41% in the pitch search