Part of the spectrum of two or more input signals is encoded using
conventional coding techniques, while encoding the rest of the spectrum
using binaural cue coding (BCC). In BCC coding, spectral components of
the input signals are downmixed and BCC parameters (e.g., inter-channel
level and/or time differences) are generated. In a stereo implementation,
after converting the left and right channels to the frequency domain,
pairs of left- and right-channel spectral components are downmixed to
mono. The mono components are then converted back to the time domain,
along with those left- and right-channel spectral components that were
not downmixed, to form hybrid stereo signals, which can then be encoded
using conventional coding techniques. For playback, the encoded bitstream
is decoded using conventional decoding techniques. BCC synthesis
techniques may then apply the BCC parameters to synthesize an auditory
scene based on the mono components as well as the unmixed stereo
components.