Patent ID: 7469206

Claim:
Decoder for decoding an encoded signal, the encoded signal including an encoded input signal representing a frequency content of an original audio signal below a predetermined frequency, and an additional information, the decoder comprising: a coding algorithm for decoding the encoded input signal to produce a decoded input signal; a reconstructor for reconstruction differences between the original audio signal and a regenerated signal based on the additional information; a high frequency generator for performing a high frequency regeneration technique to obtain the regenerated signal; a producer for producing a high frequency regenerated audio signal based on the decoded input signal, the reconstructed differences and the regenerated signal, wherein the producer is arranged for determining band pass signals for filter bank channels, into which no sine is to be inserted, in a scale factor band in accordance with the following equation { y re ⁡ ( l ) = x re ⁡ ( l ) · g hfr ⁡ ( l ) y im ⁡ ( l ) = x im ⁡ ( l ) · g hfr ⁡ ( l ) ⁢ ⁢ ∀ l l ≤ l < l u , wherein l is a filter bank channel number, wherein l l is the lowest filter bank channel number for the scale factor band, wherein l u is the highest filter bank channel for the scale factor band, wherein x re is the real part of a band pass signal sample output by the HFR block, wherein x im is an imaginary part of the band pass signal sample output by the HFR block, wherein y re and y im are the real part and the imaginary part of an adjusted band pass signal for a filter bank channel, and wherein g hfr is a gain adjustment factor derived from the noise-floor level vector.