SPLIT-BAND ENCODING AND DECODING OF AN AUDIO SIGNAL

摘要

For enabling an improved reconstruction of a high frequency band of an audio signal in a split -band coding approach, a value representative of a background noise level in an audio signal that is to be encoded is determined. Further, a gain value for the higher frequency band is determined. Further, a correction factor for the determined gain value is determined based on the determined value representative of the background noise level. The correction factor may be used at an encoding end for correcting the gain value before a corresponding codebook index is provided to a decoding end. Alternatively, the correction factor may be provided together with a codebook index for the gain value to a decoding end, and the decoding end may use the correction factor to correct the gain value if appropriate.