Patent ID: 8290783
Filing Date: 2012-10-16
Classification: G10L

Abstract:
1. An apparatus for mixing a first frame of a first input data stream and a second frame of a second input data stream to acquire an output frame of an output data stream, wherein the first frame comprises first spectral data describing a lower part of a first spectrum of a first audio signal up to a first cross-over frequency and first spectral band replication data describing a higher part of the first spectrum starting from the first cross-over frequency, wherein the second frame comprises second spectral data describing a lower part of a second spectrum of a second audio signal up to a second cross-over frequency and second SBR-data describing a higher part of the second spectrum starting from the second cross-over frequency, wherein the first and second SBR-data describe the respective higher parts of the first and second spectrum by way of energy-related values in time/frequency grid resolutions and wherein the first cross-over frequency is different from the second cross-over frequency, the apparatus comprising: a processing unit adapted to generate the output frame, the output frame comprising output spectral data describing a lower part of an output spectrum up to an output cross-over frequency and the output frame further comprising output SBR-data describing a higher part of the output spectrum above the output cross-over frequency by way of energy-related values in an output time/frequency grid resolution, wherein the processing unit is adapted such that the output spectral data corresponding to the frequencies below a minimum value of the first cross-over frequency, the second cross-over frequency and the output cross-over frequency is generated in a spectral domain based on the first and second spectral data; wherein the processing unit is further adapted such that the output SBR-data corresponding to the frequencies above a maximum value of the first cross-over frequency, the second cross-over frequency and the output cross-over frequency is processed in a SBR-domain based on the first and second SBR-data; and wherein the processing unit is further adapted such that for a frequency region between the minimum value and the maximum value, at least one SBR-value from at least one of a first and second spectral data is estimated and a corresponding SBR-value of the output SBR-data is generated, based on at least the estimated SBR-value.