Implementation of a low delay modified CELP coder at 4.8 kb/s

This paper presents a low delay high quality speech coder at low bit rates. The configuration of the speech coder is mainly composed of a formant filter, a pitch codebook, an excitation joint codebook, and post enhancement filters. The algorithm of the speech coder is briefly described. Two versions of the speech coder have been implemented in real-time with a single: ADSP-21020 chip. Both objective measurement and informal subjective listening tests show that the proposed speech coder has high quality performance.