Spectral translation/folding in the subband domain

An apparatus for reconstructing a high frequency portion of an audio signal, the apparatus comprising:

• a complex exponential modulated analysis filterbank for filtering a low frequency portion of the audio signal to produce a plurality of low frequency complex-valued subband signals, wherein the complex exponential modulated analysis filterbank includes a plurality of decimators;
• a high frequency reconstructor that reconstructs the high frequency portion of the audio signal by patching both a real and an imaginary part of a consecutive number of the plurality of low frequency complex-valued subband signals to consecutive subbands of the high frequency portion;
• and
• a complex exponential modulated synthesis filterbank for generating a wideband audio signal by combining the reconstructed high frequency portion of the audio signal with the low frequency portion of the audio signal, wherein the complex exponential modulated synthesis filterbank includes a plurality of interpolators,
• wherein the high frequency reconstructor uses a first parameter indicating a quantity of the consecutive number of the plurality of low frequency complex-valued subband signals and a second parameter indicating a reconstruction range start channel.