Patent ID: 9734832
Date: 2017-08-15
CPC Classifications: G10L,H04S

Claim:
1. An apparatus for upmixing a downmix audio signal describing one or more downmix audio channels into an upmixed audio signal describing a plurality of upmixed audio channels, the apparatus comprising: an upmixer configured to apply temporally variable upmix parameters to upmix the downmix audio signal, in order to acquire the upmixed audio signal, wherein the temporally variable upmix parameters comprise temporally variable smoothened phase values; a parameter determinator, wherein the parameter determinator is configured to acquire one or more temporally smoothened upmix parameters for usage by the upmixer on the basis of a quantized upmix parameter input information, wherein the parameter determinator is configured to combine a scaled version of a previous smoothened phase value with a scaled version of an input phase information using a phase change limitation algorithm, to determine a current smoothened phase value on the basis of the previous smoothened phase value and the input phase information.