| 摘要 |
The present document relates to audio decoding and/or audio transcoding. In particular, the present document relates to a scheme for efficiently decoding a number M of audio channels from a bitstream comprising a higher number N of audio channels. In this context a method and system for merging a first and a second source set of spectral band replication (SBR) parameters to a target set of SBR parameters is described. The first and second source set comprise a first and second frequency band partitioning, respectively, which are different from one another. The first source set comprises a first set of energy related values associated with frequency bands of the first frequency band partitioning. The second source set comprises a second set of energy related values associated with frequency bands of the second frequency band partitioning. The target set comprises a target energy related value associated with an elementary frequency band. The method comprises the steps of breaking up the first and the second frequency band partitioning into a joint grid comprising the elementary frequency band; assigning a first value of the first set of energy related values to the elementary frequency band; assigning a second value of the second set of energy related values to the elementary frequency band; and combining the first and second value to yield the target energy related value for the elementary frequency band. 301 scale factor bands 402 411 412 413 414 ch 0 -_ t 1 4 :423 44 401 Ch42l ch.1 S ,426i 1427 I 403 42 5 416 Fig. 4 415 417 201 scale tor bands - 302 ch. 53 C421--- 62 523 524 525 Fig. Sa |
