Patent ID: 11862184
Assignee: FRAUNHOFER GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 25:
26. A method for processing an encoded audio signal, the encoded audio signal comprising a sequence of access units, each access unit of the sequence of access units comprising a core audio signal with a first spectral width and parameters describing a spectrum above the first spectral width, the method comprising:
generating, from an access unit of the encoded audio signal, the core audio signal and a set of the parameters;
upsampling the core audio signal of the access unit to obtain a first upsampled spectrum and a timely consecutive second upsampled spectrum, the first upsampled spectrum and the second upsampled spectrum, both, comprising a same content as the core audio signal and comprising a second spectral width being greater than the first spectral width of the core audio signal;
converting the parameters of the access unit to acquire converted parameters being applicable to the first upsampled spectrum and the second upsampled spectrum; and
spectral gap filling processing comprising
when generating a transcoded audio signal, multiplexing the first upsampled spectrum and a first part of corresponding gap filling energy parameters to obtain a first transcoded access unit and multiplexing the second upsampled spectrum and a second part of corresponding gap filling energy parameters to obtain a second transcoded access unit, or
when decoding the encoded audio signal, applying a first part of the converted parameters to the first upsampled spectrum using a gap filling operation to obtain a first processed spectrum and applying a second part of the converted parameters to the second upsampled spectrum using a gap filling operation to obtain a second processed spectrum, performing an IMDCT operation on the first processed spectrum to obtain a first time signal, performing an IMDCT operation on the second processed spectrum to obtain a second time signal, and overlapping and adding the first time signal and the second time signal to obtain a time domain output signal.