Patent ID: 9621990
Date: 2017-04-11
CPC Classifications: G10L,H04R,H04S

Claim:
1. A method performed in an audio decoder for reconstructing N audio channels from M audio channels, the method comprising: receiving an encoded audio bitstream, the encoded audio bitstream including a downmixed audio signal and surround data, the downmixed audio signal having M audio channels and the surround data including a set of spatial parameters, the set of spatial parameters including at least one inter-channel intensity difference parameter and at least one inter-channel coherence parameter; decoding, in a surround data decoder, the surround data to produce decoded surround data; decoding, in a core decoder, the downmixed audio signal having M audio channels to obtain a decoded frequency domain representation of the M audio channels, wherein the decoded frequency domain representation of the M audio channels includes a plurality of frequency bands, and each frequency band includes one or more spectral components; reconstructing, in a surround decoder, a frequency domain representation of the N audio channels from the decoded frequency domain representation of the M audio channels, down-mixing information used to generate the downmixed audio signal and the decoded surround data; synthesizing, with one or more synthesis filterbanks, the frequency domain representation of the N audio channels to create a time domain representation of the N audio channels; and outputting the time domain representation of the N audio channels; wherein M is one or more, M is less than N, and the audio decoder is implemented at least in part with hardware.