Method and system for controlling directivity of an audio source in a virtual reality environment

1 . A method for rendering an audio signal of an audio source in a virtual reality rendering environment, the method comprising:

determining a distance of a source position of the audio source from a listening position of a listener within the virtual reality rendering environment;

determining based on the distance whether or not a directivity pattern of the audio source is to be taken into account for a listening situation of the listener within the virtual reality rendering environment;

rendering an audio signal of the audio source without taking into account the directivity pattern of the audio source, if it is determined that the directivity pattern of the audio source is not to be taken into account for the listening situation of the listener; and

rendering the audio signal of the audio source in dependence of the directivity pattern of the audio source, if it is determined that the directivity pattern is to be taken into account for the listening situation of the listener.

2 . The method of claim 1 , wherein the method comprises:

determining one or more parameters describing the listening situation; and

determining whether or not the directivity pattern of the audio source is to be taken into account based on the one or more parameters.

3 . The method of claim 2 , wherein the one or more parameters comprise:

the distance between the source position of the audio source and the listening position of the listener;

a frequency of the audio signal;

a time instant, at which the audio signal is to be rendered;

an orientation and/or a viewing direction and/or a trajectory of the listener with regards to the audio source within the virtual reality rendering environment;

a condition, notably a condition with regards to computational resources, of a renderer for rendering the audio signal; and/or

an action of the listener with regards to the virtual reality rendering environment.

4 . The method claim 1 , wherein the method comprises:

determining that the distance of the source position of the audio source from the listening position is smaller than a near field distance threshold; and

determining that the directivity pattern of the audio source is not to be taken into account; and/or

determining that the distance of the source position of the audio source from the listening position is greater than the near field distance threshold; and

determining that the directivity pattern of the audio source is to be taken into account.

5 . The method claim 1 , wherein the method comprises:

determining that the distance of the source position of the audio source from the listening position greater than a far field distance threshold; and

determining that the directivity pattern of the audio source is not to be taken into account; and/or

determining that the distance of the source position of the audio source from the listening position is smaller than the far field distance threshold; and

determining that the directivity pattern of the audio source is to be taken into account.

6 . The method of claim 1 , wherein

the near field threshold and/or the far field threshold depend on a directivity control function;

the directivity control function provides a control value as a function of the distance; and

the control value is indicative of an extent to which the directivity pattern is to be taken into account.

7 . The method claim 1 , wherein the method comprises:

determining a control value for the listening situation based on a directivity control function; wherein the directivity control function provides different control values for different listening situations; and

determining based on the control value whether or not the directivity pattern of the audio source is to be taken into account.

8 . The method of claim 7 , wherein the method comprises:

comparing the control value with a control threshold; and

determining based on the comparison, in particular depending on whether the control value is greater or smaller than the control threshold, whether or not the directivity pattern of the audio source is to be taken into account.

9 . The method of claim 8 , wherein

the directivity control function is configured to provide control values between a minimum value and a maximum value, wherein, the minimum value is 0 and/or the maximum value is 1;

the control threshold lies between the minimum value and the maximum value; and wherein

the method comprises:

determining that the directivity pattern of the audio source is not to be taken into account, if the control value for the listening situation is smaller than the control threshold; and/or

determining that the directivity pattern of the audio source is to be taken into account, if the control value for the listening situation is greater than the control threshold.

10 . The method of claim 9 , wherein the directivity control function is configured to provide control values which are below the control threshold in a listening situation, for which

the distance of the source position of the audio source from the listening position of the listener is smaller than a near field threshold; and/or

the distance of the source position of the audio source from the listening position of the listener is greater than a far field threshold.

11 . The method of claim 1 , wherein the method comprises:

determining a control value for the listening situation based on a directivity control function; wherein the directivity control function provides different control values for different listening situations; wherein the control value is indicative of an extent to which the directivity pattern is to be taken into account;

adjusting the directivity pattern of the audio source in dependence of the control value; and

rendering the audio signal of the audio source in dependence of the adjusted directivity pattern of the audio source.

12 . The method of claim 11 , wherein

adjusting the directivity pattern of the audio source comprises determining a weighted sum of the directivity pattern of the audio source with a uniform directivity pattern; and

a weight for determining the weighted sum depends on the control value.

13 . The method of claim 11 , wherein

the directivity pattern of the audio source is applicable to a reference listening situation, notably to a reference distance between the source position of the audio source and the listening position of the listener; and

the directivity control function is such that

the directivity pattern is not adjusted if the listening situation corresponds to the reference listening situation; and/or

an extent of adjustment of the directivity pattern increases with increasing deviation of the listening situation from the reference listening situation, in particular such that the directivity pattern progressively tends towards a uniform directivity pattern with increasing deviation of the listening situation from the reference listening situation.

14 . A method for rendering an audio signal of a first audio source to a listener within a virtual reality rendering environment, the method comprising,

determining a control value for a listening situation of the listener within the virtual reality rendering environment based on a directivity control function; wherein the directivity control function provides different control values for different listening situations; wherein the control value is a function of a distance between a position of the first audio source and a listening position of the listener and wherein the control value is indicative of an extent to which a directivity of an audio source is to be taken into account;

adjusting a directivity pattern of the first audio source in dependence of the control value; and

rendering the audio signal of the first audio source in dependence of the adjusted directivity pattern of the first audio source to the listener within the virtual reality rendering environment.

15 . A virtual reality audio renderer for rendering an audio signal of an audio source in a virtual reality rendering environment, wherein the audio renderer is configured to

determine a distance of a source position of the audio source from a listening position of a listener within the virtual reality rendering environment;

determine based on the distance whether or not a directivity pattern of the audio source is to be taken into account for a listening situation of the listener within the virtual reality rendering environment;

render an audio signal of the audio source without taking into account the directivity pattern of the audio source, if it is determined that the directivity pattern of the audio source is not to be taken into account for the listening situation of the listener; and

render the audio signal of the audio source in dependence of the directivity pattern of the audio source, if it is determined that the directivity pattern is to be taken into account for the listening situation of the listener.

16 . A virtual reality audio renderer for rendering an audio signal of a first audio source to a listener within a virtual reality rendering environment, wherein the audio renderer is configured to

determine a control value for a listening situation of the listener within the virtual reality rendering environment based on a directivity control function; wherein the directivity control function provides different control values for different listening situations; wherein the control value is a function of a distance between a listening position of the first audio source and a position of the listener and wherein the control value is indicative of an extent to which a directivity of an audio source is to be taken into account;

adjust a directivity pattern of the first audio source in dependence of the control value; and

render the audio signal of the first audio source in dependence of the adjusted directivity pattern of the first audio source to the listener within the virtual reality rendering environment.