Audio distribution system, an audio encoder, an audio decoder and methods of operation therefore

A method of encoding an audio signal comprising the steps of:

• receiving an input multi channel signal;
• generating a single channel signal and multi channel parameters for at least a first part of the input multi channel signal by parametric multi channel encoding;
• the multi channel parameters comprising multi channel information related to the single channel signal;
• generating multi channel intensity data in response to the input multi channel signal and the single channel signal;
• and
• generating encoded audio output data comprising the single channel signal, the intensity data and the multi channel parameters.

A multi channel audio decoder comprising:

• means for receiving (201) a single channel signal, parametrically encoded multi channel parameters comprising multi channel information related to the single channel signal and intensity encoded multi channel intensity data related to the single channel signal;
• an intensity decoder (203) for generating a first decoded signal from the single channel signal and the intensity data;
• and
• a parametric multi channel decoder (207) operable to generate a decoded multi channel output signal from the first decoded signal and the parametrically encoded multi channel parameters.

A multi channel audio decoder comprising:

• means for receiving (301) a single channel signal, parametrically encoded multi channel parameters comprising multi channel information related to the single channel signal and intensity encoded multi channel intensity data related to the single channel signal;
• an intensity decoder (303) for generating a first decoded signal from the single channel signal;
• and
• a parametric multi channel decoder (309) operable to generate a decoded multi channel output signal from the first decoded signal, the intensity data and the parametrically encoded multi channel parameters.

A method of multi channel audio decoding comprising the steps of:

• receiving a single channel signal, parametrically encoded multi channel parameters comprising multi channel information related to the single channel signal and intensity encoded multi channel intensity data related to the single channel signal;
• generating a first decoded signal from the single channel signal and the intensity data by intensity decoding;
• and
• generating a decoded multi channel output signal from the first decoded signal and the parametrically encoded multi channel parameters by parametric multi channel decoding.

A multi channel audio signal comprising:

• single channel signal data,
• intensity encoded multi channel intensity data related to the single channel signal, the multi channel intensity data being encoded in accordance with a first encoding protocol;
• and
• parametrically encoded multi channel parameters comprising multi channel information related to the single channel signal, the parametrically encoded multi channel parameters being encoded in accordance with a second encoding protocol different than the first encoding protocol.