Method and device for processing spatialized audio signals

A method for processing a spatialized multichannel audio signal that comprises a first spatialized audio signal and a second spatialized audio signal, wherein

• the first spatialized audio signal has been spatialized by a first lateral spatializer of a multichannel audio spatializer,
• the second spatialized audio signal has been spatialized by a second lateral spatializer of the multichannel audio spatializer, and
• the first spatialized audio signal differs from the second spatialized audio signal,
• the method comprising:
• by a first equalizer having a first equalizer transfer function receiving and filtering the first spatialized audio signal based on a first set of equalizer coefficients to provide a first equalized audio signal;
• and
• by a second equalizer having a second equalizer transfer function receiving and filtering the second spatialized audio signal based on a second set of equalizer coefficients to provide a second equalized audio signal, wherein:
• the first equalizer at least partly compensates for undesired coloration in the first spatialized audio signal in a mono-source scenario wherein the first spatialized audio signal equals the second spatialized audio signal;
• and
• the second equalizer at least partly compensates for undesired coloration in the second spatialized audio signal in a mono-source scenario wherein the first spatialized audio signal equals the second spatialized audio signal;
• by an equalizer controller:
• obtaining a representation of a first mono-source transfer function characterizing the first lateral spatializer and a representation of a second mono-source transfer function characterizing the second lateral spatializer;
• determining the first set of equalizer coefficients based on the representation of the first mono-source transfer function and a representation of a first predefined target transfer function,
• wherein determining the first set of equalizer coefficients comprises inverting a representation of the first mono-source transfer function;
• and
• determining the second set of equalizer coefficients based on the representation of the second mono-source transfer function and a representation of a second predefined target transfer function,
• wherein determining the second set of equalizer coefficients comprises inverting a representation of the second mono-source transfer function.

An audio device comprising:

• a processor for processing a spatialized multichannel audio signal, the spatialized multichannel audio signal comprising:
• a first spatialized audio signal and a second spatialized audio signal, wherein
• the first spatialized audio signal has been spatialized by a first lateral spatializer of a multichannel audio spatializer,
• the second spatialized audio signal has been spatialized by a second lateral spatializer of the multichannel audio spatializer, and
• the first spatialized audio signal differs from the second spatialized audio signal, the processor comprising:
• a first equalizer having a first equalizer transfer function configured to receive and filter the first spatialized audio signal based on a first set of equalizer coefficients to provide a first equalized audio signal;
• a second equalizer having a second equalizer transfer function configured to receive and filter the second spatialized audio signal based on a second set of equalizer coefficients to provide a second equalized audio signal, wherein:
• the first equalizer is configured to at least partly compensate for undesired coloration in the first spatialized audio signal in a mono-source scenario wherein the first spatialized audio signal equals the second spatialized audio signal;
• and
• the second equalizer is configured to at least partly compensate for undesired coloration in the second spatialized audio signal in a mono-source scenario wherein the first spatialized audio signal equals the second spatialized audio signal;
• an equalizer controller configured to:
• obtain a representation of a first mono-source transfer function characterizing the first lateral spatializer and a representation of a second mono-source transfer function characterizing the second lateral spatializer,
• determine the first set of equalizer coefficients based on the representation of the first mono-source transfer function and a representation of a first predefined target transfer function;
• and
• determine the second set of equalizer coefficients based on the representation of the second mono-source transfer function and a representation of a second predefined target transfer function,
• determine the first set of equalizer coefficients such that the product of the first mono-source transfer function and the first equalizer transfer function at least within a working frequency range aligns with the first predefined target transfer function, and
• determine the second set of equalizer coefficients such that the product of the second mono-source transfer function and the second equalizer transfer function at least within the working frequency range aligns with the second predefined target transfer function.