Partial access metadata for video-based point cloud compression data

1. A decoding device for generating partial access metadata for video-based point cloud compression, the decoding device comprising:

a communication interface configured to receive a compressed bitstream and metadata related to the compressed bitstream;

a processor operably coupled to the communication interface, wherein the processor is configured to:

identify, in the metadata, region information that indicates a region of a point cloud based on a user perspective;

locate a track of the compressed bitstream that corresponds to the region information;

identify, in the track, objects corresponding to the region of the point cloud; and

decode for display of an object, included in the objects identified in the track, that is visible from the user perspective.

2. The decoding device of claim 1 , wherein:

the compressed bitstream includes a supplemental enhancement information (SEI) message, and

the objects corresponding to the region of the point cloud are defined in the SEI message based on a number of the objects, a length of an object identifier, and a value of object identifiers.

3. The decoding device of claim 2 , wherein the number of the objects indicates a total number of objects in the region, the length of the object identifier indicates a length of a respective object identifier, and the value of object identifiers indicates an identifier of a respective object.

4. The decoding device of claim 2 , wherein the processor is configured to determine whether the object is visible from the user perspective based on a three-dimensional region corresponding to a location present in or bordering the region in line with the user perspective.

5. The decoding device of claim 1 , wherein the processor is further configured to:

identify, in the metadata, dynamic region information that indicates an updated track corresponding to the region information;

identify a new object in the updated track that is visible from the user perspective; and

decode the new object for display.

6. The decoding device of claim 1 , wherein the processor is further configured to:

identify, in the metadata, dynamic region information that indicates an updated track corresponding to the region information;

identify, in the track, a deleted object corresponding an object currently displayed; and

remove the deleted object from display.

7. The decoding device of claim 6 , wherein:

the compressed bitstream includes a supplemental enhancement information (SEI) message, and

the deleted object is defined in the SEI message based on a number of canceled objects, a length of an object identifier, and a value of object identifiers.

8. A method for point cloud decoding, the method comprising:

receiving, using a communication interface, a compressed bitstream and metadata related to the compressed bitstream;

identifying, using a processor operably coupled to the communication interface, region information in the metadata that indicates a region of a point cloud based on a user perspective;

locating a track of the compressed bitstream that corresponds to the region information;

identifying, in the track, objects corresponding to the region of the point cloud; and

decoding for display of an object, included in the objects identified in the track, that is visible from the user perspective.

9. The method of claim 8 , wherein:

the compressed bitstream includes a supplemental enhancement information (SEI) message, and

the objects corresponding to the region of the point cloud are defined in the SEI message based on a number of the objects, a length of an object identifier, and a value of object identifiers.

10. The method of claim 9 , wherein the number of the objects indicates a total number of objects in the region, the length of the object identifier indicates a length of a respective object identifier, and the value of object identifiers indicates an identifier of a respective object.

11. The method of claim 9 , further comprising:

determining whether the object is visible from the user perspective based on a three-dimensional region corresponding to a location present in or bordering the region in line with the user perspective.

12. The method of claim 8 , further comprising:

identifying, in the metadata, dynamic region information that indicates an updated track corresponding to the region information;

identifying a new object in the updated track that is visible from the user perspective; and

decoding the new object for display.

13. The method of claim 8 , further comprising:

identifying, in the metadata, dynamic region information that indicates an updated track corresponding to the region information;

identifying, in the track, a deleted object corresponding an object currently displayed; and

removing the deleted object from display.

14. The method of claim 13 , wherein:

the compressed bitstream includes a supplemental enhancement information (SEI) message, and

the deleted object is defined in the SEI message based on a number of canceled objects, a length of an object identifier, and a value of object identifiers.

15. A non-transitory computer readable medium embodying a computer program, the computer program comprising computer readable program code that, when executed by a processor of an electronic device, causes the electronic device to:

receive a compressed bitstream and metadata related to the compressed bitstream;

identify, in the metadata, region information that indicates a region of a point cloud based on a user perspective;

locate a track of the compressed bitstream that corresponds to the region information;

identify, in the track, objects corresponding to the region of the point cloud; and

decode for display of an object, included in the objects identified in the track, that is visible from the user perspective.

16. The non-transitory computer readable medium of claim 15 , wherein:

the compressed bitstream includes a supplemental enhancement information (SEI) message, and

the objects corresponding to the region of the point cloud are defined in the SEI message based on a number of the objects, a length of an object identifier, and a value of object identifiers.

17. The non-transitory computer readable medium of claim 16 , wherein the number of the objects indicates a total number of objects in the region, the length of the object identifier indicates a length of a respective object identifier, and the value of object identifiers indicates an identifier of a respective object.

18. The non-transitory computer readable medium of claim 16 , wherein the computer readable program code that, when executed by the processor of the electronic device, further causes the electronic device to:

determine whether the object is visible from the user perspective based on a three-dimensional region corresponding to a location present in or bordering the region in line with the user perspective.

19. The non-transitory computer readable medium of claim 15 , wherein the computer readable program code that, when executed by the processor of the electronic device, further causes the electronic device to:

identify, in the metadata, dynamic region information that indicates an updated track corresponding to the region information;

identify a new object in the updated track that is visible from the user perspective; and

decode the new object for display.

20. The non-transitory computer readable medium of claim 15 , wherein the computer readable program code that, when executed by the processor of the electronic device, further causes the electronic device to:

identify, in the metadata, dynamic region information that indicates an updated track corresponding to the region information;

identify, in the track, a deleted object corresponding an object currently displayed; and

remove the deleted object from display.