| 摘要 |
An audio processing system (100) for spatial synthesis comprises an upmix stage (110) receiving a decoded m-channel downmix signal (X) and outputting, based thereon, an n-channel upmix signal (Y), wherein 2≦̸m<n. The upmix stage comprises a downmix modifying processor (120), which receives the m-channel downmix signal and outputting a modified downmix signal (d1, d2) obtained by cross mixing and non-linear processing of the downmix signal, and further comprises a first mixing matrix (130) receiving the downmix signal and the modified downmix signal, forming an n-channel linear combination of the downmix signal channels and modified downmix signal channels only and outputting this as the n-channel upmix signal. In an embodiment, the first mixing matrix accepts one or more mixing parameters (g, α1, . . . ) controlling at least one gain in the linear combination performed by the first mixing matrix. The gains are polynomials of degree ≦̸2. |
