Method, apparatus, and system for sampling-based dynamic mesh compression are provided. The process may include determining one or more sample positions associated with an input mesh based on one or more sampling rates, and an occupancy status associated respectively with each of the one or more sample positions indicating whether each of the one or more sample positions is within boundaries of one or more polygons defined by the input mesh is determined. The process may include generating a sample-based occupancy map based on the occupancy status associated respectively with each of the one or more sample positions.

Method, apparatus, and system for sampling-based dynamic mesh compression are provided. The process may include determining one or more sample positions associated with an input mesh based on one or more sampling rates, and an occupancy status associated respectively with each of the one or more sample positions indicating whether each of the one or more sample positions is within boundaries of one or more polygons defined by the input mesh is determined. The process may include generating a sample-based occupancy map based on the occupancy status associated respectively with each of the one or more sample positions.

Devices and methods of intra prediction of a block of a picture are provided. In various embodiments, information indicating an Intra Sub-Partitions (ISP) split type can be obtained. A value of a filter flag can be set based on the ISP split type. For instance, the value of the filter flag can be set to 0 when the ISP split type does not indicate not to split a current block. A set of coefficients of an interpolation filter can then be selected according to the value of the filter flag. For instance, fG coefficients or fC coefficients can be selected based on the value of the filter flag. Still in those embodiment, the selected set of coefficients can be applied to reference samples. In some embodiments, the method removes mode dependency during selection of interpolation filter type. This could increase encoding or decoding efficiency.

Devices and methods of intra prediction of a block of a picture are provided. In various embodiments, information indicating an Intra Sub-Partitions (ISP) split type can be obtained. A value of a filter flag can be set based on the ISP split type. For instance, the value of the filter flag can be set to 0 when the ISP split type does not indicate not to split a current block. A set of coefficients of an interpolation filter can then be selected according to the value of the filter flag. For instance, fG coefficients or fC coefficients can be selected based on the value of the filter flag. Still in those embodiment, the selected set of coefficients can be applied to reference samples. In some embodiments, the method removes mode dependency during selection of interpolation filter type. This could increase encoding or decoding efficiency.

An image encoding/decoding method and apparatus are provided. An image decoding method performed by an image decoding apparatus may comprise determining prediction mode characteristic information based on a color format of a current block, determining a prediction mode type of a lower-layer block split from the current block based on the prediction mode characteristic information, obtaining the lower-layer block by splitting the current block based on the prediction mode type of the lower-layer block, and decoding the lower-layer block based on the prediction mode type of the lower-layer block. The prediction mode type of the lower-layer block comprises a first prediction mode type specifying that both an intra prediction mode and an inter prediction mode are available, a second prediction mode type specifying that only the intra prediction mode is available and a third prediction mode type specifying that only the inter prediction mode is available. Based on a first condition for the current block being satisfied, the prediction mode characteristic information has a first value, and the first condition comprises a case where a color format of the current block is a monochrome format or a 4:4:4 format. Based on the first condition for the current block being not satisfied, the prediction mode characteristic information has a second value or a third value based on at least one of a color format, split mode or size of the current block.

A picture may be divided into sub-pictures/slices/tiles. For example, the picture may be divided into sub-picture(s), and subpicture-related information may be used for coding. The sub-picture-related information may be generated by an encoding device and transmitted to a decoding device. According to embodiments of the present document, sub-picture-related information can be efficiently signaled.

This application provides a method for selecting a neighbor point of a current point in a point cloud. The method includes: determining, from point cloud data, a target region where the current point is located, the target region comprising a plurality of points; determining, for at least two decoded target points in the target region, a weight coefficient of each of the at least two target points, the at least two target points not comprising the current point; determining a weight of each of the at least two target points according to the weight coefficient and geometry information of each of the at least two target points and geometry information of the current point; and selecting at least one from the at least two target points according to the weight of each of the at least two target points as the neighbor point of the current point.

This application provides a method for selecting a neighbor point of a current point in a point cloud. The method includes: determining, from point cloud data, a target region where the current point is located, the target region comprising a plurality of points; determining, for at least two decoded target points in the target region, a weight coefficient of each of the at least two target points, the at least two target points not comprising the current point; determining a weight of each of the at least two target points according to the weight coefficient and geometry information of each of the at least two target points and geometry information of the current point; and selecting at least one from the at least two target points according to the weight of each of the at least two target points as the neighbor point of the current point.

The invention relates to a method and a device for decoding an image by means of a partition unit comprising an additional region. The method of decoding an image by means of a partition unit comprising an additional region comprises the steps of: partitioning, by reference to a syntax element acquired from a received bit stream, an encoded image, which is included in the bitstream, in at least one partition unit; define an additional region for at least one partition unit; and decoding the encoded image based on the partition unit for which the additional region is defined. The invention improves the image coding efficiency.

An example device includes one or more processors, and memory storing instructions that when executed by the processors, cause the processors to receive points that represent a point cloud in three-dimensional space, and generate a data structure representing the point cloud. Generating the data structure includes encoding a position of each point in each dimension as a sequence of bits according to a tree data structure; partitioning each of the sequences into two or more portions according to a scaling depth; determining that a subset of the points is spatially isolated from a remainder of the points; quantizing each of the portions associated with the subset of the points according to a first quantization step size; quantizing each of the portions associated with the remainder of the points according to a second quantization step size; and including the quantized portions in the data structure.