Patent ID: 11922957
Assignee: FRAUNHOFER GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 13:
14. An encoder for encoding a downmix matrix, the downmix matrix mapping a plurality of input channels of an audio content to a plurality of output channels, the input and output channels being associated with respective speakers at predetermined positions relative to a listener position, the encoder comprising:
a processor configured to encode the downmix matrix wherein encoding the downmix matrix comprises exploiting a symmetry of speaker pairs of the plurality of input channels and a symmetry of speaker pairs of the plurality of output channels,
wherein respective pairs of input and output channels in the downmix matrix have associated respective mixing gains for adapting a level by which a given input channel contributes to a given output channel,
wherein, for encoding the downmix matrix, the processor is configured to encode significance values, wherein respective significance values are assigned to pairs of symmetric speaker groups of the input channels and symmetric speaker groups of the output channels, wherein a significance value indicates if a mixing gain for one or more of the input channels is zero or not, and
wherein encoding the significance values is based on a template, the template having the same pairs of speaker groups of the input channels and speaker groups of the output channels as the downmix matrix, wherein respective template significance values are assigned to pairs of symmetric speaker groups of the input channels and symmetric speaker groups of the output channels of the template.