KR-20260065856-A - Point cloud data transmission device, point cloud data transmission method, point cloud data reception device and point cloud data reception method

KR20260065856AKR 20260065856 AKR20260065856 AKR 20260065856AKR-20260065856-A

Abstract

A method and apparatus for decoding point cloud data are disclosed. A method for decoding point cloud data according to embodiments may include the steps of receiving geometry data, attribute data, and signaling information, decoding the geometry data based on the signaling information, and decoding the attribute data based on the signaling information.

Inventors

오현묵

Assignees

엘지전자 주식회사

Dates

Publication Date: 20260511
Application Date: 20240905
Priority Date: 20230905

Claims (15)

A step of receiving geometry data, attribute data, and signaling information; A step of decoding the geometry data based on the signaling information; and A point cloud data decoding method comprising the step of decoding attribute data based on the above signaling information.
In Article 1, The above geometry data is divided and included in data units of a layer group structure, and A point cloud data decoding method in which geometry data of the current data unit of the current layer group is decoded by referring to context information of the data unit of the upper layer group stored in memory.
In Article 2, The above memory is managed by data unit, and The memory referenced to decode the geometry data of the above-mentioned current data unit is divided into a context state storage area, a reference count information storage area, and a counter information storage area, and The above context state storage area stores context information of the data unit of the upper layer group, and The above reference count information storage area stores the number of data units referencing the data units of the upper layer group for each layer group constituting the layer group structure, and A point cloud data decoding method in which the above counter information storage area stores counter information that is updated whenever a data unit of the upper layer group is used for each layer group.
In claim 3, the step of decoding the geometry data A point cloud data decoding method that does not store the context information of the current data unit of the decoded current layer group in memory if there is no subsequent data unit referencing the context information of the current data unit.
In claim 3, the step of decoding the geometry data A point cloud data decoding method that does not store context information of the current data unit of the decoded current layer group in memory when the current layer group is the last layer group in the above layer group structure.
In claim 5, the step of decoding the geometry data A point cloud data decoding method that, in the above layer group structure, excludes layer groups for which decoding is skipped, and if the current layer group is the last layer group, does not store context information of the current data unit of the decoded current layer group in the memory.
In claim 3, the step of decoding the geometry data A point cloud data decoding method for determining the release of context information of a data unit of an upper layer group based on a value stored in a reference count information storage area of the memory and a value stored in a count information storage area.
In claim 2, the signaling information A point cloud data decoding method comprising information for identifying a data unit of the upper layer group referenced to decode geometry data of the current data unit.
In claim 2, the signaling information It includes information related to the number of reference data units per layer group stored in the reference count storage area of the above memory, and The above information is a point cloud data decoding method that is signaled by dividing it into layer groups.
A receiver that receives geometry data, attribute data, and signaling information; A geometry decoder that decodes the geometry data based on the signaling information; and A point cloud data decoding device comprising an attribute decoder that decodes the attribute data based on the above signaling information.
In Article 10, The above geometry data is divided and included in data units of a layer group structure, and The above geometry decoder is a point cloud data decoding device that decodes geometry data of a current data unit of a current layer group by referring to context information of a data unit of an upper layer group stored in memory.
In Article 10, The above memory is managed by data unit, and The memory referenced to decode the geometry data of the above-mentioned current data unit is divided into a context state storage area, a reference count information storage area, and a counter information storage area, and The above context state storage area stores context information of the data unit of the upper layer group, and The above reference count information storage area stores the number of data units referencing the data units of the upper layer group for each layer group constituting the layer group structure, and The above counter information storage area is a point cloud data decoding device that stores counter information that is updated whenever a data unit of the upper layer group is used for each layer group.
In claim 12, the geometry decoder is A point cloud data decoding method for determining the release of context information of a data unit of an upper layer group stored in a context state storage area based on a value stored in a reference count information storage area of the memory and a value stored in a count information storage area.
Step of encoding geometry data; Step of encoding attribute data; and A point cloud data encoding method comprising the step of transmitting the encoded geometry data, the encoded attribute data, and signaling information.
Geometry encoder that encodes geometry data; An attribute encoder that encodes attribute data; and A point cloud data encoding device comprising a transmission unit that transmits the encoded geometry data, the encoded attribute data, and signaling information.

Description

Point cloud data transmission device, point cloud data transmission method, point cloud data reception device and point cloud data reception method Point cloud data transmission device, point cloud data transmission method, point cloud data reception device and point cloud data reception method The embodiments relate to a method and apparatus for processing point cloud content. Point cloud content is content represented as a point cloud, which is a set of points belonging to a coordinate system that represents a three-dimensional space or volume. Point cloud content can represent three-dimensional media and is used to provide various services such as VR (Virtual Reality), AR (Augmented Reality), MR (Mixed Reality), XR (Extended Reality), and autonomous driving services. However, representing point cloud content requires tens of thousands to hundreds of thousands of point data points. Therefore, a method is required to efficiently process a vast amount of point data. In other words, there is a problem in that a large amount of throughput is required to transmit and receive point cloud data. Therefore, encoding for compression and decoding for decompression are performed during the process of transmitting and receiving point cloud data; however, due to the large size of the point cloud data, the computations are complex and time-consuming. Drawings are included to further understand the embodiments, and the drawings illustrate the embodiments along with descriptions related to the embodiments. FIG. 1 shows an example of a point cloud content provision system according to embodiments. FIG. 2 is a block diagram illustrating a point cloud content provision operation according to embodiments. FIG. 3 shows an example of a point cloud encoder according to embodiments. FIG. 4 shows examples of octree and occupancy codes according to embodiments. Figure 5 shows an example of a point configuration by LOD according to embodiments. Figure 6 shows an example of a point configuration by LOD according to embodiments. FIG. 7 shows an example of a point cloud decoder according to embodiments. FIG. 8 is an example of a transmission device according to embodiments. FIG. 9 is an example of a receiving device according to embodiments. FIG. 10 shows an example of a structure that can be linked with a point cloud data transmission/reception method/device according to embodiments. FIGS. 11 and FIGS. 12 are diagrams illustrating the encoding, transmission, and decoding processes of point cloud data according to embodiments. FIG. 13 is a diagram showing an example of a layer-based point cloud data configuration according to embodiments. FIG. 14 (a) shows the bitstream structure of geometry data according to embodiments, and FIG. 14 (b) shows the bitstream structure of attribute data according to embodiments. FIG. 15 is a diagram showing an example of the configuration of a bitstream for dividing and transmitting the bitstream into layers according to embodiments. FIG. 16 illustrates an example of a bitstream alignment method when a geometry bitstream and an attribute bitstream are multiplexed into a single bitstream according to embodiments. FIG. 17 illustrates another example of a bitstream alignment method when a geometry bitstream and an attribute bitstream are multiplexed into a single bitstream according to embodiments. FIGS. 18(a) to 18(c) are drawings showing examples of symmetric geometry-attribute selection according to embodiments. FIGS. 19(a) to 19(c) are drawings showing examples of asymmetric geometry-attribute selection according to embodiments. FIGS. 20(a) to 20(c) illustrate examples of methods for configuring slices containing point cloud data according to embodiments. FIGS. 21(a) and FIGS. 21(b) show a single slice and divided slice-based geometry tree structure according to embodiments. FIGS. 22(a) and FIGS. 22(b) show the layer group structure of a geometry coding tree and the aligned layer group structure of an attribute coding tree according to the embodiments. FIG. 23 shows a layer group and subgroup structure according to embodiments. FIG. 24 shows an example of context reference between layer groups according to embodiments. FIG. 25 shows an example of context reference between groups according to embodiments. FIG. 26 (a) to (c) shows examples of context buffer management according to embodiments. FIG. 27 (a) to (c) shows examples of context buffer management according to embodiments. FIG. 28 (a) to (c) shows examples of context buffer management according to embodiments. FIG. 29 (a) to (c) illustrates a context buffer release method according to embodiments. FIG. 30 illustrates a context buffer release method according to embodiments. FIG. 31 illustrates a context memory management method according to embodiments. FIG. 32 shows a bitstream containing point cloud data according to embodiments. FIG. 33 shows an example of a syntax structure of a sequence parameter set (SPS) of a bitstream according to embodim