A system comprises an encoder configured to compress attribute information and/or spatial information for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. The encoder is configured to convert a point cloud into an image based representation. The encoder packs patch images into an image frame and fills empty spaces in the image frame with a padding. The encoder is also configured to determine quantized minimum depths and/or maximum depths patch images in the image frames, wherein depth information is signaled relative to the quantized minimum depth.

A three-dimensional data encoding method includes: dividing three-dimensional points included in point cloud data into processing units each of which includes one or more of the three-dimensional points; and encoding attribute information of a current three-dimensional point included in a current processing unit, by reference to an encoded processing unit, to generate a bitstream.

A point cloud decoding method comprises: parsing a bitstream of a point cloud to obtain reconstructed information of position information of a target point in the point cloud; obtaining predicted values of attribute information of the target point according to the reconstruction information of the position information of the target point; parsing the bitstream to obtain residual values of the attribute information of the target point; obtaining initial reconstructed values of the attribute information of the target point according to the predicted values and the residual values of the attribute information of the target point; filtering the initial reconstructed values of the attribute information of the target point by using a Kalman filtering algorithm, to obtain final reconstructed values of the attribute information of the target point; and obtaining a decoded point cloud according to the final reconstructed values of the attribute information of the target point.

A method for level partition of a point cloud includes: decoding a point cloud bitstream, the point cloud bitstream including geometry information and attribute information of the point cloud; determining a maximum permissible value of a first syntax element in the point cloud bitstream; parsing the point cloud bitstream to determine a value of the first syntax element according to the maximum permissible value; determining, according to the value of the first syntax element, a number of levels of detail (LODs) in a process of decoding the attribute information; and decoding the attribute information according to the number of the LODs and the geometry information, to determine a reconstructed point cloud of the point cloud.

Point cloud coding methods, an encoder, and a decoder are provided. The method includes the following. Morton codes for a point cloud are obtained according to geometry information of the point cloud after geometry decoding is completed and the geometry information is reconstructed. The point cloud is determined as an input point cloud of an iteration. Morton codes for an input point cloud of an i-th iteration are right shifted by K bits according to a number of points in the input point cloud of the i-th iteration, where K is a positive integer. A point is selected from points with a same value of Morton codes after right shifted by K bits. An i-th level of detail (LOD) layer is formed with the point selected. Color information is decoded according to the LOD layer.

Methods, apparatus, systems and articles of manufacture for video coding using object metadata are disclosed. An example apparatus includes an object separator to separate input views into layers associated with respective objects to generate object layers for geometry data and texture data of the input views, a pruner to project the first object layer of a first basic view of the at least one basic views against the first object layer of a first additional view of the at least one additional views to generate a first pruned view and a first pruning mask, a patch packer to tag a patch with an object identifier of the first object, the patch corresponding to the first pruning mask, and an atlas generator to generate at least one atlas to include in encoded video data, the atlas including the patch.

A three-dimensional data encoding method includes: adding a first information item to a bitstream, the first information item indicating whether a duplicated point is available, the duplicated point representing, using a single node, position information items of two or more three-dimensional points having a same position information item in a prediction tree showing a reference relation in predictive encoding; and adding second information items to the bitstream when the first information item indicates that the duplicated point is available, the second information items each corresponding to a different one of nodes included in the prediction tree, and indicating a total number of one or more three-dimensional points included in the different one of the nodes.

A three-dimensional data encoding method includes: obtaining an attribute information item of a three-dimensional point; executing an encoding process that executes a transform process on a numerical value indicated by the attribute information item and encodes the attribute information item or that encodes the attribute information item without executing the transform process, the transform process performing at least one of scaling or offset, the scaling performing at least one of a multiplication and division operation or a shift operation, the offset performing an addition and subtraction operation; and generating a bitstream including the attribute information item encoded and a transform identification information item indicating whether the transform process has been executed.

A three-dimensional data encoding method includes: calculating a prediction residual that is a difference between information of a three-dimensional point included in point cloud data and a predicted value; and generates a bitstream including first information with respect to the prediction residual, second information indicating a bit count of the first information, and third information indicating a bit count of the second information.

Methods and devices for coding point clouds using direct coding mode to code coordinates of a point within a sub-volume associated with a current node instead of a pattern of occupancy for child nodes. Eligibility for use of direct coding is based on occupancy data from another node. If eligible, then a flag is represented in the bitstream to signal whether direct coding is applied to points in the sub-volume or not.