SPEECH CODING APPARATUS AND SPEECH DECODING APPARATUS

摘要

First codebook (61) and second codebook (62) respectively have two subcodebooks, and in respective codebooks, addition sections (66) and (67) obtain respective excitation vectors by adding sub-excitation vectors fetched from respective two subcodebooks. Addition section (68) obtains an excitation sample by adding those excitation vectors. According to the aforementioned constitution, it is possible to store sub-excitation vectors with different characteristics in respective subcodebooks. Therefore, it is possible to correspond to input signals with various characteristics, and achieve excellent sound qualities at the time of decoding.