SPEECH DECODING DEVICE, SPEECH ENCODING DEVICE, SPEECH DECODING METHOD, AND SPEECH ENCODING METHOD

摘要

PROBLEM TO BE SOLVED: To obtain a reproduction signal in which a pre-echo and a post-echo are sufficiently improved.SOLUTION: A speech decoding device 1 comprises: a non-multiplexing unit 1a; a low frequency band decoding unit 1b; a band dividing filter bank unit 1c; an encoding train analysis unit 1d; an encoding train decoding/inverse quantization unit 1e; a high frequency band generation unit 1h; low frequency band time envelope calculation units 1f-1ffor acquiring the time envelopes of a plurality of low frequency bands; a time envelope calculation unit 1g for calculating the time envelope of a high frequency band using time envelope information and the time envelopes of a plurality of low frequency bands; a time envelope adjustment unit 1i for adjusting the time envelope of a high frequency band component using the time envelope acquired by the time envelope calculation unit 1g; and a band synthesizing filter bank unit 1j.SELECTED DRAWING: Figure 1