Patent ID: 8295507

Claim:
A frequency band extending apparatus for extending a frequency band of an input signal, comprising: an extension control device configured to determine an extension start band for the input signal; a band dividing device configured to divide the input signal into a plurality of sub-band signals, wherein the frequency band is extended based on a plurality of sub-band signals on a side higher than the extension start band obtained by multiplying a plurality of sub-band signals on a side lower than the extension start band with gain adjusting coefficients determined for sub-band signals on a side higher than the extension start band, wherein the plurality of sub-band signals on a side lower than the extension start band immediately precedes the extension start band; a transient detecting device configured to subject a predetermined number of the sub-band signals on a side lower than the extension start band and preceding the extension start band to transient detection in a temporal direction; and a group dividing device configured to divide the predetermined number of sub-band signals into a plurality of groups in the temporal direction, based on a transient detection result generated by the transient detecting device.