Abstract There are two representations for Higher Order Ambisonics denoted HOA: spatial domain and coefficient domain. The in 5 vention provides a method and apparatus for decoding an HOA representation, said decoding comprising: de-multiplexing multiplexed vector of PCM encoded spatial domain signals and vector of PCM encoded and normalized coefficient domain sig nals; transforming the vector of PCM encoded spatial domain 10 signals to a corresponding vector of coefficient domain sig nals by multiplying the vector of PCM encoded spatial domain signals with a transform matrix; de-normalizing the vector of PCM encoded and normalized coefficient domain signals; combining the vector of coefficient domain signals and the 15 vector of de-normalized coefficient domain signals to deter mine a combined vector of HOA coefficient domain signals that can have a variable number of HOA coefficients. Fig.3 Encoder Decoder SpaCiMUX-HOA DE Coefficint 11 12 13 14 15 Fig. 1 Encoder 1/ Decoder d Separate d2 PCM °° Combine d' - H HOA xX H OA -+, Coefficients 26 d'2 Coig27 28 d'2 Coefficients 29 | 0d'2 d'2 d'1 To W1 PCM W1 HOA DE- w I To Spatial Coig MUX M MUX Coefficient Domain Coig|u Domain 21 22 23 24 25 Fig. 2 e Encoder Decoder D Searae DAdaptive D'2 C Adaptive D''2 Combine D HOA Norma- -PCoig'-o De-Norma- HOA Coefficients lization Coig lization Coefficients |30 36 347 d' 38 D2 39 D' D1 To PCM I HOA 5DE-W1 T Spatial oding MUX MUX Coefficient Domain Domain 31 32 33 34 35 Fig. 3
Method and apparatus for generating from a coefficient domain representation of HOA signals a mixed spatial/coefficient domain representation of said HOA signals