Abstract: A method of encoding input signals (l, r) to generate encoded data (100) is provided. The method involves processing the input signals (l, r) to determine first parameters (?1,?2) describing relative phase difference and temporal difference between the signals (l, r), and applying these first parameters (?1, ?2) to process the input signals to generate intermediate signals. The method involves processing the intermediate signals to determine second parameters (?; IID,?) describing angular rotation of the first intermediate signals to generate a dominant signal (m) and a residual signal (s), the dominant signal (m) having a magnitude or energy greater than that of the residual signal (s). These second parameters are applicable to process the intermediate signals to generate the dominant (m) and residual (s) signals.

Abstract: The present invention relates to a method of encoding and decoding an audio signal. The invention further relates to an arrangement for encoding and decoding an audio signal. The invention further relates to a computer-readable medium comprising a data record indicative of an audio signal and a device for communicating an audio signal having been encoded according to the present invention. By the method of encoding, a double description of the signal is obtained, where the encoding comprises two encoding steps, a first standard encoding and an additional second encoding. The second encoding is able to give a coarse description of the signal, such that a stochastic realization can be made and appropriate parts can be added to the decoded signal from the first decoding. The required description of the second encoder in order to make the realization of a stochastic signal possible requires a relatively low bit rate, while other double/multiple descriptions require a much higher bit rate.

Abstract: An audio signal having at least two channels can be efficiently down-mixed into a downmix signal and a residual signal, when the down-mixing rule used depends on a spatial parameter that is derived from the audio signal and that is post-processed by a limiter to apply a certain limit to the derived spatial parameter with the aim of avoiding instabilities during the up-mixing or down-mixing process. By having a down-mixing rule that dynamically depends on parameters describing an interrelation between the audio channels, one can assure that the energy within the down-mixed residual signal is as minimal as possible, which is advantageous in the view of coding efficiency. By post processing the spatial parameter with a limiter prior to using it in the down-mixing, one can avoid instabilities in the down- or up-mixing, which otherwise could result in a disturbance of the spatial perception of the encoded or decoded audio signal.