PARAMETRIC STEREO ENCODING/DECODING HAVING DOWNMIX OPTIMISATION

摘要

The present invention relates to a method for parametric encoding of a stereo digital audio signal comprising a step of encoding (312) a mono signal produced by downmixing (307) applied to the stereo signal and encoding spatialisation information (315, 316) of the stereo signal. Said method is characterised in that downmixing comprises calculating (330), using the frequency coefficient, the amplitude of the mono signal according to the amplitudes of the channels of the stereo signal, and determining (331), for a predetermined set of frequency coefficients, the phase of the mono signal by calculating the phase of the signal by means of the channels of the stereo signal. The transmission of spatialisation information is also suitable, according to the invention, for said downmixing. The invention also relates to the relevant decoding method, and to the encoder and decoder implementing said respective methods.