SPECTRUM ENCODING DEVICE, SPECTRUM DECODING DEVICE, ACOUSTIC SIGNAL TRANSMISSION DEVICE, ACOUSTIC SIGNAL RECEPTION DEVICE, AND METHODS THEREOF

摘要

There is provided a spectrum encoding device capable of performing encoding with a low bit rate and a high quality. The device includes: means for subjecting a first signal to a frequency conversion and calculating a first spectrum; means for subjecting a second signal to a frequency conversion and calculating a second spectrum; means for estimating the shape of the second spectrum of the FL <= k < FH band by using a filter having the first spectrum of the 0 <= k < FL band as an internal state; and means for encoding the rough shape of the second spectrum decided according to the coefficient representing the filter characteristic at this time.