Apparatus, methods, and computer programs for encoding spatial metadata

1. An apparatus comprising processing circuitry; and memory circuitry including computer program code, the memory circuitry and the computer program code configured to, with the processing circuitry, cause the apparatus to:

obtain spatial metadata associated with spatial audio content;

obtain a configuration parameter comprising, at least, an indication of an input source format of the spatial audio content;

use, at least, the configuration parameter to select a method of compression of, at least in part, the spatial metadata associated with the spatial audio content; and

provide the selected method of compression for processing.

2. An apparatus as claimed in claim 1 , wherein using the configuration parameter to select the method of compression comprises causing the apparatus to use the configuration parameter to select a codebook to compress the spatial metadata associated with the spatial audio content.

3. An apparatus as claimed in claim 1 , wherein using the configuration parameter to select the method of compression comprises causing the apparatus to use the configuration parameter to enable a codebook for compressing the spatial metadata, to be created, wherein the selected method of compression comprises, at least, the codebook.

4. An apparatus as claimed in claim 2 , wherein providing the selected method of compression for processing comprises causing the apparatus to use the selected codebook to encode the spatial metadata.

5. An apparatus as claimed in claim 1 , wherein the indication of the input source format comprises an indication of at least one of:

at least one configuration of microphones used to capture the spatial audio content,

at least one configuration of channels used to represent the spatial audio content,

at least one type of device used to capture the spatial audio content, or

whether a source of the spatial audio content contains elevation.

6. An apparatus as claimed in claim 1 , wherein the spatial metadata comprises data indicative of spatial parameters of the spatial audio content.

7. An apparatus as claimed in claim 1 , wherein the apparatus is configured to select the method of compression independently of the spatial audio content, wherein the selected method of compression comprises a method of compression defined based, at least partially, on at least one characteristic of the input source format of the spatial audio content.

8. An apparatus as claimed in claim 1 , wherein the apparatus is configured to cause obtaining of the spatial audio content.

9. An apparatus as claimed in claim 8 , wherein the apparatus is configured to obtain the configuration parameter with the spatial audio content.

10. An apparatus as claimed in claim 8 , wherein the apparatus is configured to obtain the configuration parameter separately from the spatial audio content.

11. An apparatus as claimed in claim 1 , wherein the apparatus is configured to cause transmitting of a compressed version of the spatial metadata to a decoding device.

12. A method comprising:

obtaining spatial metadata associated with spatial audio content;

obtaining a configuration parameter comprising, at least, an indication of an input source format of the spatial audio content;

using, at least, the configuration parameter to select a method of compression of, at least in part, the spatial metadata associated with the spatial audio content; and

providing the selected method of compression for processing.

13. A method as claimed in claim 12 , wherein the using of the configuration parameter to select the method of compression comprises using the configuration parameter to select a codebook to compress the spatial metadata associated with the spatial audio content.

14. An apparatus comprising processing circuitry; and memory circuitry including computer program code, the memory circuitry and the computer program code configured to, with the processing circuitry, cause the apparatus to:

receive, from an encoding device, spatial audio content;

receive, from the encoding device, compressed spatial metadata associated with the spatial audio content;

receive, from the encoding device, information indicative of a method used to compress, at least in part, spatial metadata associated with the spatial audio content, wherein the information indicative of the method comprises information indicative of a method selected based on a configuration parameter comprising, at least, an indication of an input source format of the spatial audio content; and

provide the information indicative of the method for processing.

15. An apparatus as claimed in claim 14 , wherein the information indicative of the method used to compress the spatial metadata comprises the configuration parameter.

16. An apparatus as claimed in claim 14 , wherein the information indicative of the method used to compress the spatial metadata comprises an indication of a codebook that was selected using the configuration parameter.

17. An apparatus as claimed in claim 14 , further comprising one or more transceivers, wherein receiving the spatial audio content comprises causing the apparatus to:

receive, with the one or more transceivers from the encoding device, the spatial audio content,

wherein receiving the compressed spatial metadata comprises causing the apparatus to:

receive, with the one or more transceivers from the encoding device, the compressed spatial metadata.

18. A method comprising:

receiving, from an encoding device, spatial audio content;

receiving, from the encoding device, compressed spatial metadata associated with the spatial audio content;

receiving, from the encoding device, information indicative of a method used to compress, at least in part, spatial metadata associated with the spatial audio content, wherein the information indicative of the method comprises information indicative of a method selected based on a configuration parameter comprising, at least, an indication of an input source format of the spatial audio content; and

providing the information indicative of the method for processing.

19. A method as claimed in claim 18 , wherein the information indicative of the method used to compress the spatial metadata comprises the configuration parameter.

20. A method as claimed in claim 18 , wherein the information indicative of the method used to compress the spatial metadata comprises an indication of a codebook that was selected using the configuration parameter.