Abstract: A point cloud encoding apparatus and a point cloud decoding apparatus are provided for effectively encoding and decoding point cloud data. The point cloud encoding apparatus is configured for obtaining auxiliary information of a union occupancy map corresponding to a point cloud group, where the point cloud group includes N frames of point clouds, N?2, and N is an integer; the union occupancy map is a union set of occupancy maps of N patches having a matching relationship in the N frames of point clouds; and the auxiliary information of the union occupancy map is used to determine auxiliary information of the N patches; and encoding a syntax element into a bitstream, where the syntax element includes the auxiliary information of the union occupancy map. The technical solutions provided in this application help reduce bitstream transmission overheads without affecting encoding and decoding performance.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for performing motion estimation. In some implementations, a method includes generating a segmentation of point cloud data based on continuity data of the point cloud data. A representation of the segmented point cloud data is projected onto sides of a three-dimensional bounding box. Patches are generated based on the projected representation of the segmented point cloud data. A first frame of the patches is generated. First and second auxiliary information is generated using the first frame and a reference frame. A first patch from the first frame is identified that matches a patch from the reference frame based on the first and second auxiliary information. A motion vector candidate is generated between the first and second patch based on a difference between the first and second auxiliary information. Motion compensation is performed using the motion vector candidate.

Abstract: A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a plurality of coded sequences of point cloud coding (PCC) frames, wherein the plurality of coded sequences of PCC frames represent a plurality of PCC attributes including geometry, texture, and one or more of reflectance, transparency, and normal. Each coded PCC frame is represented by one or more PCC network abstraction layer (NAL) units. The mechanism also includes parsing the bitstream to obtain an indication for each of the PCC NAL units that indicates whether each of the PCC NAL units belongs to a corresponding one of the PCC attributes, and to which of the PCC attributes the PCC NAL unit belongs when the PCC NAL unit belongs to the corresponding PCC attribute. The mechanism also includes decoding the bitstream based on the indications.

Abstract: A point cloud encoding method is provided to improve coding efficiency. The method includes: obtaining global matched patches in N frames of point clouds in a point cloud group; determining M union patch occupancy maps corresponding to M sets, where a union patch occupancy map corresponding to an mth set is a union set of occupancy maps of all global matched patches in the mth set; packing the M union patch occupancy maps to obtain a global occupancy map; packing each of the N frames of point clouds to obtain occupancy maps of the N frames of point clouds; and encoding the N frames of point clouds based on the occupancy maps of the N frames of point clouds.

Abstract: A video coding mechanism is disclosed. The mechanism includes receiving a bitstream comprising a plurality of coded sequences of point cloud coding (PCC) frames. The plurality of coded sequences of PCC frames represent a plurality of PCC attributes including geometry, texture, and one or more of reflectance, transparency, and normal. Each coded PCC frame is represented by one or more PCC network abstraction layer (NAL) units. The mechanism also includes parsing the bitstream to obtain, for each PCC attribute, an indication of one of a plurality of video codecs used to code the corresponding PCC attribute. The mechanism also includes decoding the bitstream based on the indicated video codecs for the PCC attributes.

Abstract: Embodiments of this application disclose a point cloud coding method and a coder. The method includes: obtaining description information of a bounding box size of a to-be-encoded point cloud and a normal axis of a to-be-encoded patch in the to-be-encoded point cloud, where the description information of the bounding box size of the to-be-encoded point cloud and the normal axis of the to-be-encoded patch are used to determine a tangent axis of the to-be-encoded patch and a bitangent axis of the to-be-encoded patch; and encoding a syntax element into a bitstream, where the syntax element includes an index of the normal axis of the to-be-encoded patch and information for indicating the description information of the bounding box size of the to-be-encoded point cloud, and the syntax element is used to indicate the tangent axis of the to-be-encoded patch and the bitangent axis of the to-be-encoded patch.

Abstract: A method and Video-Based Point Cloud Compression (V-PCC) decoder for synchronization of decoded frames before point cloud reconstruction is provided. A V-PCC bit-stream which includes encoded frames associated with a point cloud sequence is received. Sub-streams of the received V-PCC bit-stream are decoded by a group of video decoders of the V-PCC decoder to generate V-PCC components, such as an attribute component, a geometry component, an occupancy map component, and an atlas component. A release of the attribute component, the geometry component, the occupancy map component, and the atlas component to the reconstruction unit is delayed based on a first output delay, a second output delay, a third output delay, and a fourth output delay, respectively. The delayed release synchronizes the attribute component, the geometry component, the occupancy map component, and the atlas component with each other before the reconstruction unit reconstructs a point cloud based on the V-PCC components.

Abstract: An apparatus comprises a processor configured to obtain a point cloud, make a choice between octree encoding or quadtree encoding of a parent node, and encode the parent node into a bitstream based on the choice; and a transmitter coupled to the processor and configured to transmit the bitstream. An apparatus comprises a receiver configured to receive a bitstream; and a processor coupled to the receiver and configured to parse from the bitstream a first parameter indicating a depth of PCC, decode first nodes before the depth using octree decoding, parse from the bitstream a second parameter indicating a node coding mode for second nodes at and after the depth, and decode the second nodes based on the second parameter.

Abstract: Provided are a method and apparatus for encoding or decoding a 360-degree image. According to an image decoding method and apparatus according to an embodiment, an original 360-degree image is reconstructed by acquiring image data from a bitstream, decoding a projection image of a 360-degree image from the image data, converting the projection image into the 360-degree image, acquiring rotation information of the 360-degree image from the bitstream, and rotating the 360-degree image based on the rotation information.

Abstract: A method for obtaining a global matched patch is provided, including: obtaining patch sets of N frames of point clouds; performing a matching operation on one or more patches in a matched patch set of a reference frame of an ith frame in the N frames and one or more unmatched patches in a patch set of the ith frame, to obtain a matched patch set of the ith frame, where the matched patch set of the ith frame includes n patches; and determining M global matched patch sets based on matched patch sets of the N frames, where at least one of the M global matched patch sets is a set of patches that have a matching relationship across N1 frames, and the N1 frames represent at least a portion of the N frames. This method helps improve video coding efficiency.

Abstract: Provided is an image processing method including: generating an omnidirectional spherical image; determining information regarding a director's view that indicates some regions of the omnidirectional spherical image; generating a projection image by projecting the omnidirectional spherical image to a development view of a polyhedron; dividing, from the projection image, a director's view projection image corresponding to the director's view, based on the information regarding the director's view; reshaping the director's view projection image into a director's view rectangular image by moving a location of at least one of pixels of the director's view projection image; and generating a bitstream which the director's view rectangular image is encoded into.

Abstract: A method comprises obtaining a first weight for a first probability associated with a first probability update window; obtaining a second weight for a second probability associated with a second probability update window, wherein the first weight and the second weight are unequal; and coding, using the first weight and the second weight, a portion of a video.

Abstract: Provided is an image processing method including: generating an omnidirectional spherical image; determining information regarding a director's view that indicates some regions of the omnidirectional spherical image; generating a projection image by projecting the omnidirectional spherical image to a development view of a polyhedron; dividing, from the projection image, a director's view projection image corresponding to the director's view, based on the information regarding the director's view; reshaping the director's view projection image into a director's view rectangular image by moving a location of at least one of pixels of the director's view projection image; and generating a bitstream which the director's view rectangular image is encoded into.

Abstract: Provided are a method and apparatus for encoding or decoding a 360-degree image. An image decoding method and apparatus according to an embodiment include: obtaining image data from a bitstream; decoding a first region of a projection image corresponding to a non-clipping region of a 360-degree image from the image data; obtaining information about a clipping region of the 360-degree image from the bitstream; determining a second region of the projection image, based on the information about the clipping region; and converting the projection image including the first region and the second region into the 360-degree image.

Abstract: Provided are a method and apparatus for encoding or decoding a 360-degree image. According to an image decoding method and apparatus according to an embodiment, an original 360-degree image is reconstructed by acquiring image data from a bitstream, decoding a projection image of a 360-degree image from the image data, converting the projection image into the 360-degree image, acquiring rotation information of the 360-degree image from the bitstream, and rotating the 360-degree image based on the rotation information.