Encoding and decoding a set of signals
An encoding device ( 1 ) and method convert a set of signals (l, r) into a dominant signal (m) containing most signal energy, a residual signal (s) containing a remainder of the signal energy, and signal parameters (IID, ICC) associated with the conversion. The dominant signal (m) and selected parts of the residual signal (s) are encoded. Selecting parts of the residual signal involves a residual signal (s′) passing perceptually relevant parts of the residual signal (s), attenuating perceptually less relevant parts of the residual signal and suppressing least relevant parts of the residual signal. An associated decoding device ( 2 ) and method decode the encoded dominant signal and the encoded residual signal so as to produce a decoded dominant signal (m′ u ) and a decoded residual signal (s′ mod ) respectively. A synthetic residual signal (s′ Syn ) is derived from the decoded dominant signal (m′ u ) and is attenuated so as to produce an attenuated synthetic residual signal (S′ Syn,mod ). The attenuated synthetic residual signal (S syn,mod ) and the decoded residual signal (S′ mod ) are combined to produce a reconstructed residual signal (s′). The decoded dominant signal (m′) and the reconstructed residual signal (s′) are then converted into a set of output signals (l′, r′).
1. An encoding device for encoding a set of input signals, the device comprising:
conversion means for converting the set of input signals into a dominant signal containing most signal energy, a residual signal containing a remainder of the signal energy, and signal parameters associated with the conversion;
selection means for selecting parts of the residual signal; and
encoding means for encoding the dominant signal and the selected parts of the residual signal,
wherein the selection means substantially passes perceptually relevant parts of the residual signal, attenuates perceptually less relevant parts of the residual signal, and suppresses least relevant parts of the residual signal.
2. The encoding device as claimed in claim 1 , wherein the selection means includes a weighting function having at least three distinct weighting values.
3. The encoding device as claimed in claim 2 , wherein the weighting function is time and/or frequency dependent.
4. The encoding device as claimed in claim 1 , wherein said encoding device further comprises:
multiplexing means for multiplexing the encoded signals and the signal parameters into a combined output signal.
5. The encoding device as claimed in claim 1 , wherein said encoding device further comprises:
quantization means quantizing the signal parameters.
6. An audio system, comprising an encoding device as claimed in claim 1 .
7. A method of encoding a set of input signals, the method comprising the steps of:
converting the set of input signals into a dominant signal containing most signal energy, a residual signal containing a remainder of the signal energy, and signal parameters associated with the conversion;
selecting parts of the residual signal; and
encoding the dominant signal and the selected parts of the residual signal,
wherein the selecting step comprises the sub-steps of substantially passing perceptually relevant parts of the residual signal, attenuating perceptually less relevant parts of the residual signal, and suppressing least relevant parts of the residual signal.
8. The method as claimed in claim 7 , wherein the selecting step involves a weighting function having at least three distinct weighting values.
9. The method as claimed in claim 8 , wherein the weighting function is time and/or frequency dependent.
10. A non-transitory computer-readable medium containing a computer program for causing a computer, when executing said computer program, to carry out the encoding method as claimed in claim 7 .