Stereo encoding device, stereo decoding device, and stereo encoding method

Abstract

There is disclosed a stereo encoding device capable of accurately encoding a stereo signal at a low bit rate and suppressing delay in audio communication. The device performs monaural encoding in its first layer (). In a second layer (), a filtering unit () generates an LPC (Linear Predictive Coding) coefficient and generates a left channel drive sound source signal. A time region evaluation unit () and a frequency region evaluation unit () perform signal evaluation and prediction in both of their regions. A residual encoding unit () encodes a residual signal. A bit distribution control unit () adaptively distributes bits to the time region evaluation unit (), the frequency region evaluation unit (), and the residual encoding unit () according to a condition of the audio signal.