Transmission device of point cloud data and method performed by transmission device, and reception device of point cloud data and method performed by reception device

A reception device of point cloud data, the reception device comprising:

• a memory;
• and
• at least one processor,
• wherein the at least one processor is configured to:
• obtain geometry-based point cloud compression (G-PCC) file including the point cloud data, and
• wherein the G-PCC file includes information on a sample group in which samples in the G-PCC file are grouped based on one or more temporal levels, and
• wherein the G-PCC file further includes information on the temporal levels,
• extract one or more samples belonging to a target temporal level from the samples in the G-PCC file based on the information on the sample group and the information on the temporal levels,
• wherein the information on the temporal levels comprises number information indicating a number of temporal levels and temporal level identification information for identifying the temporal levels.

A transmission device of point cloud data, the transmission device comprising:

• a memory;
• and
• at least one processor,
• wherein the at least one processor is configured to:
• generate information on a sample group in which geometry-based point cloud compression (G-PCC) samples are grouped based on one or more temporal levels, and
• generate a G-PCC file including the information on the sample group, the information on the temporal levels and the point cloud data,
• wherein the information on the temporal levels comprises number information indicating a number of temporal levels and temporal level identification information for identifying the temporal levels.