Determining the inter-channel time difference of a multi-channel audio signal

Abstract

There is provided a method and device for determining an inter-channel time difference of a multi-channel audio signal having at least two channels. A set of local maxima of a cross-correlation function involving at least two different channels of the multi-channel audio signal is determined (S) for positive and negative time-lags, where each local maximum is associated with a corresponding time-lag. From the set of local maxima, a local maximum for positive time-lags is selected as a so-called positive time-lag inter-channel correlation candidate and a local maximum for negative time-lags is selected as a so-called negative time-lag inter-channel correlation candidate (S). When the absolute value of a difference in amplitude between the inter-channel correlation candidates is smaller than a first threshold, it is evaluated whether there is an energy-dominant channel (S). When there is an energy-dominant-channel, the sign of the inter-channel time difference is identified and a current value of the inter-channel time difference is extracted based on either the time-lag corresponding to the positive time-lag inter-channel con-elation candidate or the time-lag corresponding to the negative time-lag inter-channel correlation candidate (S).