Abstract: A method of decoding a point cloud comprises: reconstructing a position of a point of the point cloud; determining a quantized attribute value for the point; deriving a quantization parameter (QP) bit depth offset for the point; deriving a QP range for the point based on the QP bit depth offset for the point; determining a quantization step size for the point based on the QP range for the point; and inverse quantizing the quantized attribute value for the point based on the quantization step size for the point.

Abstract: A device for encoding a point cloud comprises a memory configured to store point cloud data for the point cloud; and one or more processors configured to: determine a residual value associated with a current point of the point cloud, the residual value associated with the current point being a radius residual or an azimuth residual; determine a context for entropy encoding the residual value based on whether the current point is coded with intra prediction or inter prediction; and entropy encode the residual value using the determined context.

Abstract: A G-PCC coder may determine an occupancy of a reference child node in a reference node, wherein the reference node is in a reference frame of point cloud data used for inter prediction of a current node in a current frame of the point cloud data. The G-PCC coder may further determine a context for decoding a current occupancy bit of a current child node of the current node based on the occupancy of the reference child node, and arithmetic decode the current occupancy bit using the context.

Abstract: A device for encoding or decoding point cloud data may be configured to, responsive to determining to predict a current point in a current frame using an inter prediction mode: identify a reference frame; derive one or more motion compensated reference points from the reference frame; selectively resample points in the reference frame based on the one or more motion compensated reference points to generate a resampled reference frame; and inter predict the current point in the current frame based on the resampled reference frame.

Abstract: A device for decoding a point cloud includes a memory configured to store data representing the point cloud and one or more processors implemented in circuitry and configured to: decode a residual value; determine whether residual prediction is to be applied to a current point of the point cloud; in response to determining that residual prediction is to be applied to the current point of the point cloud: determine a residual predictor and add the residual predictor to the residual value to determine a final residual value; determine a predictor used to predict a current point of the point cloud; and use the predictor and the final residual value to determine a position of the current point.

Abstract: Provided are systems and methods for processing 360-degree video data. In various implementations, a spherical representation of a 360-degree video frame can be segmented into a top region, a bottom region, and a middle region. The middle region can be mapped into one or more rectangular areas of an output video frame. The top region can be mapped into a first rectangular area of the output video frame using a mapping that converts a square to a circle, such that pixels in the circular top region are expanded to fill the first rectangular region. The bottom region can be mapped into a second rectangular area of the output video frame such that pixels in the circular bottom region are expanded to fill the second rectangular region.

Abstract: An apparatus configured for point cloud compression may be configured to code a first syntax element indicating a number of bits used to encode one or more second syntax elements, wherein the one or more second syntax elements indicate one or more of an offset of a bounding box, an origin point of the bounding box, a size of the bounding box, or a number of unique segments. The apparatus may code the first syntax element using an exponential Golomb code. The apparatus may further code the one or more second syntax elements using a fixed length code based on the number of bits indicated by the first syntax element, and code the point cloud based on the decoded one or more second syntax elements.

Abstract: An example device for decoding point cloud data includes memory configured to store the point cloud data and one or more processors implemented in circuitry and coupled to the memory. The one or more processors are configured to determine dimensions of a region box and determine dimensions of a slice bounding box. The one or more processors are also configured to decode a slice of the point cloud data associated with the slice bounding box. The dimensions of the region box are constrained to not exceed the dimensions of the slice bounding box.

Abstract: An example device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: generate an intra-prediction block for a current block of video data using an angular intra-prediction mode, the angular intra-prediction mode being an upper-right angular intra-prediction mode or a lower-left angular intra-prediction mode; determine a prediction direction of the angular intra-prediction mode; for at least one sample of the intra-prediction block for the current block: calculate a gradient term for the at least one sample along the prediction direction; and combine a value of an intra-predicted sample of the intra-prediction block at a position of the at least one sample of the intra-prediction block with the gradient term to produce a value of the at least one sample of the intra-prediction block; and decode the current block using the intra-prediction block.

Abstract: Example devices and techniques are disclosed for incorporating temporal identification information in geometry point cloud compression syntax structures. An example device for decoding point cloud data includes memory configured to store the point cloud data and one or more processors implemented in circuitry and communicatively coupled to the memory. The one or more processors are configured to determine a value of a temporal identifier (ID) of a syntax structure and decode the point cloud data based on the value of the temporal ID. The temporal ID of the syntax structure identifies a temporal layer to which point cloud data associated with the syntax structure belongs.

Abstract: A device for decoding encoded point cloud data can be configured to, for a point of a point cloud, determine a first color value for a first color component based on a first predicted value and a first residual value; apply a scaling factor to the first residual value to determine a predicted second residual value, wherein the scaling factor has one or both of a non-integer value or an absolute value greater than one; for the point of the point cloud, receive a second residual value in the encoded point cloud data; determine a final second residual value based on the predicted second residual value and the received second residual value; and for the point of the point cloud, determine a second color value for a second color component based on a second predicted value and the final second residual value.

Abstract: Techniques are described for improving intra-subpartitioning (ISP) mode for splitting coding blocks into sub-blocks. In some cases, whether ISP mode is enabled for a coding block is based on size constraints pertaining to data units (e.g., VPDUs, transform blocks, among others). For instance, based on a size constraint related to a VPDU, the ISP mode can be disabled for coding blocks crossing VPDU boundaries. In some cases, whether to enable ISP mode may be based on comparison of the width and/or height of the coding block to size thresholds corresponding to one or more maximum transform block sizes. In some cases, where the ISP mode is enabled for a coding block, a value of a flag used for defining a type of split, horizontal or vertical, for the coding block, can be inferred based on the width and/or height of the coding block relative to one or more thresholds.

Abstract: A method comprises: for each of a plurality of dimensions: identifying a reference position for the dimension, the reference position for the dimension being a position in a reference frame for the respective dimension, and the reference frame for the respective dimension and a reference frame for at least one other dimension in the plurality of dimensions being different reference frames in a plurality of reference frames; identifying an inter predictor for the respective dimension, wherein a predictor has a coordinate value in the respective dimension corresponding to a coordinate value in the respective dimension of the inter predictor for the respective dimension; and encoding or decoding the current point based on the predictor.

Abstract: A video coder performs a Most-Probable Mode (MPM) derivation process that derives one or more MPMs for a current block that is not coded using affine linear weighted intra prediction (ALWIP). As part of performing the MPM derivation process, the video coder determines whether a neighboring block of the current block is an ALWIP-coded neighboring block. Based on the neighboring block being an ALWIP-coded neighboring block, the video coder determines that a value of an intra prediction mode of the neighboring block is a value indicating a planar mode. The video coder codes the current block based on one of the MPMs for the current block.

Abstract: A method of decoding point cloud data comprises: determining that the point cloud data is split into a plurality of largest prediction units (LPUs), wherein at least two of the LPUs have different sizes along different directions; performing inter prediction to determine predicted points for the LPUs; and reconstructing points within the LPUs based on the predicted points for the LPUs.

Abstract: A method of decoding video data includes generating a prediction block for a current block of the video data and decoding a residual block for the current block of the video data. The method includes combining the prediction block and the residual block to generate a reconstructed block of the video data and determining a variable M×N sample pattern based on a block size of the current block. The method includes estimating a local luma level for samples of the reconstructed block using the variable M×N sample pattern and applying, based on the estimated local luma level, a deblocking filter to the samples of the reconstructed block to generate filtered samples. The method includes generating final samples of the video data based on the filtered samples.

Abstract: A method of decoding video data includes determining, by one or more processors implemented in circuitry, a partition of the video data into a plurality of blocks. The partition of the video data applies a block size restriction to prevent a splitting of a block of the plurality of blocks that would result in a small block comprising a block width and a block height when the block height times the block width is less than a threshold. The method further includes generating, by the one or more processors, prediction information for the block and determining, by the one or more processors, a predicted block for the block based on the prediction information. The method further includes decoding, by the one or more processors, a residual block for the block and combining, by the one or more processors, the predicted block and the residual block to decode the block.

Abstract: An example device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: generate an intra-prediction block for a current block of video data using an angular intra-prediction mode, the angular intra-prediction mode being an upper-right angular intra-prediction mode or a lower-left angular intra-prediction mode; determine a prediction direction of the angular intra-prediction mode; for at least one sample of the intra-prediction block for the current block: calculate a gradient term for the at least one sample along the prediction direction; and combine a value of an intra-predicted sample of the intra-prediction block at a position of the at least one sample of the intra-prediction block with the gradient term to produce a value of the at least one sample of the intra-prediction block; and decode the current block using the intra-prediction block.

Abstract: An example device for processing point cloud data includes a memory configured to store the point cloud data and one or more processors implemented in circuitry and coupled to the memory. The one or more processors are configured to count a number of edges of a cube of point cloud data comprising a vertex. The one or more processors are configured to set a variable based on a total of the counting. The one or more processors are also configured to process the point cloud data based on the variable.

Abstract: An example device for coding (encoding or decoding) video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: determine a first number of neighboring blocks to a current block of the video data that are intra-predicted; determine a second number of the neighboring blocks that are inter-predicted; determine a first weight value to be applied to intra-prediction samples of an intra-prediction block for the current block; determine a second weight value to be applied to inter-prediction samples of an inter-prediction block for the current block; generate a prediction block for the current block as a weighted combination of the intra-prediction block to which the first weight value is applied and the inter-prediction block to which the second weight value is applied; and code the current block using the prediction block.