Rendering of audio objects using discontinuous rendering-matrix updates

An audio information processing apparatus for processing audio information that includes object data, wherein the audio information processing apparatus comprises one or more processors configured to:

• receive one or more signals that convey the object data representing aural content and spatial metadata for each of one or more audio objects, wherein the spatial metadata contains data representing a location in space relative to a reference position in a playback system;
• process the object data and configuration information to calculate rendering matrix coefficients for use in rendering signals in the playback system, wherein the configuration information describes a configuration of acoustic transducers in a set of acoustic transducers for the playback system;
• calculate a measure of update performance from the calculated rendering matrix coefficients and the object data according to psychoacoustic principles relating to the audibility of artifacts created by changes to rendering matrix coefficients, and deriving matrix update parameters from the measure of update performance;
• generate updated matrix coefficient values in response to the rendering matrix coefficients and the matrix update parameters;
• update the rendering matrix coefficients in response to the updated matrix coefficient values;
• and
• either
• assemble an encoded representation of the object data and the rendering matrix coefficients into an encoded output signal,
• or
• apply the rendering matrix to the object data representing the aural content of audio objects to generate audio output signals representing the aural content of rendered audio objects for respective audio channels.

A non-transitory medium recording a program of instructions that is executable by a device to perform a method for processing audio information that includes object data, wherein the method comprises:

• receiving one or more signals that convey the object data representing aural content and spatial metadata for each of one or more audio objects, wherein the spatial metadata contains data representing a location in space relative to a reference position in a playback system;
• processing the object data and configuration information to calculate rendering matrix coefficients for use in rendering signals in the playback system, wherein the configuration information describes a configuration of acoustic transducers in a set of acoustic transducers for the playback system;
• calculating a measure of update performance from the calculated rendering matrix coefficients and the object data according to psychoacoustic principles relating to the audibility of artifacts created by changes to rendering matrix coefficients, and deriving matrix update parameters from the measure of update performance;
• generating updated matrix coefficient values in response to the rendering matrix coefficients and the matrix update parameters;
• updating the rendering matrix coefficients in response to the updated matrix coefficient values;
• and
• either
• assembling an encoded representation of the object data and the rendering matrix coefficients into an encoded output signal,
• or
• applying the rendering matrix to the object data representing the aural content of audio objects to generate audio output signals representing the aural content of rendered audio objects for respective audio channels.