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 method of encoding a point cloud includes determining that residual values for all components except one component of an attribute of a point in the point cloud are equal to zero; based on the determination that the residual values for all components except the one component of the attribute are equal to zero, determining a value for the one component that is equal to a magnitude of a residual value of the one component of the attribute minus an offset; encoding the value of the one component; and signaling the encoded value in a bitstream.

Abstract: Decoding an encoded data signal representing a multi-view video sequence representing an omnidirectional video and having a first view and a second view. The decoding includes reading from the signal parameters to obtain a homographic matrix, representing transformation of a plane of the second view into a plane of the second view. An image of the second view has an active zone including pixels which, when projected via the homographic matrix onto an image of the first view, are included in the image of the first view. An image of the second view is decoded by generating a reference image having pixel values determined from previously reconstructed pixels of an image of the first view and the homographic matrix and, for a block of the image of the second view, the reference image generated is included in the list of reference images when the block belongs to the active zone.

Abstract: A method of encoding at least one image divided into blocks, implementing: encoding a first syntax element associated with a characteristic of the at least one image; encoding, for a current block to be encoded associated with at least one encoding parameter, the data of the current block; if the first syntax element is encoded according to a first predefined value representing the characteristic of the image, a second syntax element representing the value of the at least one encoding parameter is encoded only if the current block belongs to a predefined zone of the image; if the first syntax element is encoded according to a second predefined value representing the characteristic of the image, the second syntax element is encoded, whether or not the current block belongs to the predefined zone.

Abstract: A device comprises one or more processors configured to: obtain a value for a first laser, the value for the first laser indicating a number of probes in an azimuth direction of the first laser; decode a syntax element for a second laser, wherein the syntax element for the second laser indicates a difference between the value for the first laser and a value for the second laser, the value for the second laser indicating a number of probes in the azimuth direction of the second laser; determine the value for the second laser indicating the number of probes in the azimuth direction of the second laser based on the first value and the indication of the difference between the value for the first laser and the value for the second laser; and decode a point based on the number of probes in the azimuth direction of the second laser.

Abstract: An example device for decoding point cloud data includes: a memory configured to store point cloud data; and one or more processors implemented in circuitry and configured to: decode a frame of the point cloud data including a plurality of points, each of the points being associated with position values defining a respective position of the point; determine a global scaling factor for the frame; and scale the position values of each of the points by the global scaling factor. The scaling may be clipped to prevent the points exceeding the boundaries of a corresponding bounding box including respective points.

Abstract: A method comprises obtaining a first laser angle; obtaining a second laser angle; obtaining a laser angle difference for a third laser angle; determining a predicted value based on the first laser angle and the second laser angle; and determining the third laser angle based on the predicted value and the laser angle difference for the third laser angle.

Abstract: In some examples, a method of decoding a point cloud includes determining a first slice QP value for a first component of an attribute in a slice of point cloud data. The method also includes decoding a first delta QP value for the first component of the attribute for a region in the slice and determining a first region QP value for the first component of the attribute in the region from the first slice QP value and from the first delta QP value. The method further includes decoding a second delta QP value for the second component of the attribute for the region and determining a second region QP value for the second component of the attribute in the region from the second delta QP value. The method includes decoding the point cloud data based on the first and second region QP values.

Abstract: A method of decoding point cloud data comprises obtaining a bitstream that includes an arithmetically encoded syntax element indicating a vertical plane position of a planar mode of a node; and decoding the vertical plane position of the planar mode in the node, wherein decoding the vertical plane position of the planar mode comprises: determining a laser index of a laser candidate in a set of laser candidates, wherein the determined laser index indicates a laser beam that intersects the node; determining a context index based on whether the laser beam is above a first distance threshold, between the first distance threshold and a second distance threshold, between the second distance threshold and a third distance threshold, or below the third distance threshold; and arithmetically decoding the vertical plane position of the planar mode using a context indicated by the determined context index.

Abstract: In some examples, a method of decoding a point cloud includes decoding an initial QP value from an attribute parameter set. The method also includes determining a first QP value for a first component of an attribute of point cloud data from the initial QP value. The method further includes determining a QP offset value for a second component of the attribute of the point cloud data and determining a second QP value for the second component of the attribute from the first QP value and from the QP offset value. The method includes decoding the point cloud data based on the first QP value and further based on the second QP value.

Abstract: A method of decoding point cloud data comprises obtaining a bitstream that includes an arithmetically encoded syntax element indicating a vertical point position offset within a node of a tree that represents 3-dimensional positions of points in a point cloud represented by the point cloud data; and decoding the vertical point position offset, wherein decoding the vertical point position offset comprises: determining a laser index of a laser candidate in a set of laser candidates, wherein the determined laser index indicates a laser beam that intersects the node; determining a context index based on whether the laser beam is above a first distance threshold, between the first distance threshold and a second distance threshold, between the second distance threshold and a third distance threshold, or below the third distance threshold; and arithmetically decoding a bin of the vertical point position offset using a context indicated by the determined context index.

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 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: A method for decoding point cloud data comprises, based on a comparison of a maximum difference value and a threshold, applying an inverse function to a set of one or more jointly coded values to recover (i) residual values for attribute values of a current point of point cloud data and (ii) a predictor index that indicates a predictor in a predictor list, wherein predictors in the predictor list are based on attribute values of one or more neighbor points; determining predicted attribute values based on the predictor index; and reconstructing the attribute values of the current point based on the residual values and the predicted attribute values.

Abstract: A video decoder can be configured to determine that a new scaling list for a set of scaling lists is to be predicted from a reference scaling list, wherein the new scaling list corresponds to a new scaling matrix; receive a syntax element that identifies an ID number corresponding to a scaling list of the set of scaling lists that is to be used as the reference scaling list; determine that the set of scaling lists does not include a scaling list with the ID number; and in response to determining that the set of scaling lists does not include the scaling list with the ID number, determine the new scaling matrix based on a set of default values.

Abstract: A video decoder can be configured to receive a syntax element indicating whether chroma scaling matrices are signaled for the video data; in response to determining that chroma scaling matrices are signaled for the video data, determine a chroma scaling matrix for a block of video data; determine a block of chroma transform coefficients for the block of video data; dequantize a first chroma transform coefficient of the block of chroma transform coefficients using a first scaling value from the chroma scaling matrix; dequantize a second chroma transform coefficient of the block of chroma transform coefficients using a second scaling value from the chroma quantization matrix; and determine a chroma residual block for the block of video data based on the first dequantized chroma transform coefficients and the second dequantized chroma transform coefficient.

Abstract: A method for decoding a data stream representative of an image sequence. At least one current block of a current image in the image sequence is encoded using a predictor block of a reference image, the predictor block being identified in the reference image via location information. An information item enabling the reference image to be identified from a set of reference images is obtained. When the reference image satisfies a predetermined criterion, the location information of the predictor block is decoded using a first decoding mode, otherwise the location information of the predictor block is decoded using a second decoding mode, the first and second decoding modes including at least a different decoding parameter. The current block is then reconstructed from the predictor block.

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: An example device for coding a point cloud includes a memory configured to store the point cloud and one or more processors communicatively coupled to the memory. The one or more processors are configured to determine a value of a numerator syntax element, the value of the numerator syntax element being indicative of a numerator of a scale factor of the point cloud. The one or more processors are configured to determine a value of a denominator syntax element, the value of the denominator syntax element being indicative of a denominator of the scale factor of the point cloud. The one or more processors are configured to process the point cloud at least in part based on the scale factor of the point cloud.

Abstract: A method of encoding video data includes determining a first rate-distortion value associated with encoding a first chroma block of a coding unit of the video data with a first transform type, determining a second rate-distortion value associated with encoding the first chroma block of the coding unit of the video data with a second transform type, determining that the first transform type provides better rate-distortion than second transform type based on the first rate-distortion value and the second rate-distortion value, based on the determination that the first transform type provides better rate-distortion, determining a third rate-distortion value associated with encoding the coding unit with joint coding of chroma residuals (JCCR) with the first transform type, and avoiding determining a fourth rate-distortion value associated with encoding the coding unit with JCCR with the second transform type, and encoding the coding unit with JCCR with the first transform type.