An apparatus and a method for encoding an audio signal

摘要

An apparatus for decoding (100) an encoded audio signal (102), the encoded audio signal (102) comprising a first portion (104a) encoded in accordance with a first encoding algorithm, a second portion (104b) encoded in accordance with a second encoding algorithm, BWE parameters (106) for the first portion (104a) and the second portion (104b) and a coding mode information (108) indicating a first decoding algorithm or a second decoding algorithm, comprises a first decoder (110a), a second decoder (110b), a BWE module (130) and a controller (140). The first decoder (110a) decodes the first portion (104a) in accordance with the first decoding algorithm for a first time portion of the encoded signal (102) to obtain a first decoded signal (114a). The second decoder (110b) decodes the second portion (104b) in accordance with the second decoding algorithm for a second time portion of the encoded signal (102) to obtain a second decoded signal (114b). The BWE module (130) has a controllable crossover frequency (fx) and is configured for performing a bandwidth extension algorithm using the first decoded signal (114a) and the BWE parameters (106) for the first portion (104b), and for performing a bandwidth extension algorithm using the second decoded signal (114b) and the bandwidth extension parameter (106) for the second portion (104b). The controller (140) controls the crossover frequency (fx) for the BWE module (130) in accordance with the coding mode information (108).