Patent ID: 8473301

Claim:
A method for decoding an audio signal, comprising: obtaining a lower-band signal component of an audio signal in a received code stream when the audio signal switches from a first bandwidth to a second bandwidth which is narrower than the first bandwidth; extending the lower-band signal component to obtain higher-band information; performing a time-varying fadeout process on the higher-band information obtained through extension to obtain a processed higher-band signal component; and synthesizing the processed higher-band signal component and the obtained lower-band signal component; wherein performing a time-varying fadeout process on the higher-band information further comprises: performing a separate time-varying fadeout process on the higher-band information; or performing a hybrid time-varying fadeout process on the higher-band information; wherein the higher-band information is a higher-band signal component and the step of performing a separate time-varying fadeout process on the higher-band information further comprises: performing a time-domain shaping on the higher-band signal component obtained through extension by using a time-domain gain factor; or performing a frequency-domain higher-band signal component obtained through extension by using time-varying filtering; and wherein after performing a time-domain shaping on the higher-band signal component obtained through extension by using a time-domain gain factor, the method further comprises: performing a frequency-domain time-domain shaped higher-band signal component by using time-varying filtering.