Audio processing

An apparatus for processing an input audio signal in accordance with spatial metadata so as to play back a spatial audio signal in a device in dependence of at least one sound reproduction characteristic of the device, the apparatus comprising at least one processor and at least one memory including computer program code, when executed by the at least one processor, cause the apparatus to:

• obtain said input audio signal;
• obtain said spatial metadata, separate from obtaining said input audio signal, wherein said input audio signal and said spatial metadata convey a spatial audio image;
• obtain said at least one sound reproduction characteristic of the device;
• derive a first target covariance matrix based on said spatial metadata, wherein the first target covariance matrix represents sounds included in a first portion of the spatial audio image and comprises sound directions within a front region of the spatial audio image;
• derive a second target covariance matrix based on said spatial metadata and the at least one sound reproduction characteristic of the device, wherein the second target covariance matrix represents sounds included in a second portion of the spatial audio image, wherein the second portion comprises sound directions that are not included in the first portion;
• and
• render the spatial audio signal based on the input audio signal and in dependence of the first and second target covariance matrices.