Point cloud data transmission device, point cloud data transmission method, point cloud data reception device, and point cloud data reception method

1. A method of transmitting point cloud data, the method comprising:

encoding geometry data of the point cloud data;

encoding attribute data of the point cloud data based on the geometry data; and

transmitting the encoded geometry data, the encoded attribute data, and signaling data,

wherein the encoded geometry data is included in a plurality of slices,

wherein the signaling data includes flag information for indicating whether or not a context of a current slice is referenced by at least one other slice and slice identification information for identifying the current slice, and

wherein the context of the current slice is not stored in a buffer of a receiving system for at least one other slice based on the flag information indicating that the context of the current slice is not referenced by the at least one other slice.

2. The method of claim 1 ,

wherein the context of the current slice is stored in the buffer of the receiving system for decoding the at least one other slice based on the flag information indicating that the context of the current slice is referenced by the at least one other slice.

3. The method of claim 1 ,

wherein the signaling data further includes information identifying a number of times the context of the current slice is referenced based on the context of the current slice being referenced by the at least one other slice.

4. An apparatus for transmitting point cloud data, the apparatus comprising:

a geometry encoder configured to encode geometry data of the point cloud data;

an attribute encoder configured to encode attribute data of the point cloud data based on the geometry data; and

a transmitter configured to transmit the encoded geometry data, the encoded attribute data, and signaling data,

wherein the encoded geometry data is included in a plurality of slices,

wherein the signaling data includes flag information for indicating whether or not a context of a current slice is referenced by at least one other slice and slice identification information for identifying the current slice, and

wherein the context of the current slice is not stored in a buffer of a receiving system for at least one other slice based on the flag information indicating that the context of the current slice is not referenced by the at least one other slice.

5. The apparatus of claim 4 ,

wherein the context of the current slice is stored in the buffer of the receiving system for decoding the at least one other slice based on the flag information indicating that the context of the current slice is referenced by the at least one other slice.

6. The apparatus of claim 4 , wherein the signaling data further includes information identifying a number of times the context of the current slice is referenced based on the context of the current slice being referenced by the at least one other slice.

7. A method of receiving point cloud data, the method comprising:

receiving geometry data, attribute data, and signaling data;

decoding the geometry data based on the signaling data;

decoding the attribute data based on the signaling data and the decoded geometry data; and

rendering the point cloud data based on the signaling data, the decoded geometry data, and the decoded attribute data,

wherein the geometry data is included in a plurality of slices,

wherein the signaling data includes flag information for indicating whether or not a context of a current slice is referenced by at least one other slice and slice identification information for identifying the current slice, and

wherein, based on the flag information indicating that the context of the current slice is not referenced by the at least one other slice, the context of the current slice is not stored in a buffer for at least one other slice.

8. The method of claim 7 ,

wherein the signaling data further includes information identifying a number of times the context of the current slice is referenced based on the context of the current slice being referenced by the at least one other slice.

9. The method of claim 7 , wherein, based on the flag information indicating that the context of the current slice is referenced by the at least one other slice the context of the current slice is stored in the buffer for decoding the at least one other slice.

10. An apparatus for receiving point cloud data, the apparatus comprising:

a receiver configured to receive geometry data, attribute data, and signaling data;

a geometry decoder configured to decode the geometry data based on the signaling data;

an attribute decoder configured to decode the attribute data based on the signaling data and the decoded geometry data; and

a renderer configured to render the point cloud data based on the signaling data, the decoded geometry data, and the decoded attribute data,

wherein the geometry data is included in a plurality of slices,

wherein the signaling data includes flag information for indicating whether or not a context of a current slice is referenced by at least one other slice and slice identification information for identifying the current slice, and

wherein, based on the flag information indicating that the context of the current slice is not referenced by the at least one other slice, the context of the current slice is not stored in a buffer for at least one other slice.

11. The apparatus of claim 10 ,

wherein the signaling data further includes information identifying a number of times the context of the current slice is referenced based on the context of the current slice being referenced by the at least one other slice.

12. The apparatus of claim 10 ,

wherein, based on the flag information indicating that the context of the current slice is referenced by the at least one other slice, the context of the current slice is stored in the buffer for decoding the at least one other slice.