Methods for encoding multichannel input signals and computer-readable invariant media

Abstract

The invention relates to a method (600) and an encoding block (100) for encoding a multi-channel input signal (101) comprising N different channels. The method (600) comprises steps, for the current frame of a sequence of frames, to determine (601) whether the current frame is active or inactive by using a voice and / or signal activity detector, and to determine (602) the down-level signal (103) based on the multi-channel input signal (101), wherein the down-level signal (103) comprises N or fewer channels. In addition, method (600) includes the step of determining (603) the gain metadata (105) including the set of parameters to be generated, based on the downsignal (103), the reconstructed multi-channel signal (111) includes N channels, where the gain metadata (105) is determined depending on whether the current frame is an active or inactive frame. Method (600) also includes the step of encoding (604) the gain metadata (105) into a bit stream. The invention also relates to a method (610) and a decoding block (150) for decoding bit streams and computer-readable bit media.