On a Improvement of Pitch Search Time for Real Time Implementation in IMBE Vocoder

IMBE Vocoder 실시간 처리를 위한 피치 검색 시간 개선에 관한 연구

IMBE(Improved Multi-Band Excitation) vocoders exhibit good performance at low data rates. The major drawback to IMBE coders is their large computational requirements. In this paper, thus, we propose a new pitch search method that preserves the quality of the IMBE vocoder with reduced complexity. The basic idea is to skip unnecessary range of the pitch searching by using the quantization error. Applying the proposed method to the IMBE vocoder, we can get approximately $45.88\%$ processing time reduction and there is no difference in voice quality between conventional IMBE and proposed IMBE.