Abstract: The embodiments relate to a method and a technical equipment for implementing the method. The method comprises (210) creating a scene structure for a three-dimensional media content, wherein the scene structure comprises three-dimensional data for objects of the three-dimensional media content; (220) determining dependency information for the objects, which dependency information indicates an external factor on which an object is dependent on; (230) storing a scene description defining the objects and their dependency information into a bitstream structure; (240) and transferring a generated scene description to a renderer.

Abstract: An example embodiment relates to a method comprising: receiving (700), by a client device, information about a scene associated with a 3D presentation for initiating viewport rendering by an application, wherein said scene is hosted by a server as one or more encoded 2D patches, said 2D patches being projections of the 3D representation of the scene; providing (702) the server with information for selecting 2D patches required to reconstruct at least one segment of the 3D scene as visible in a given viewport; obtaining (704), from the server, one or more video bitstreams generated based on the selected 2D patches and related metadata for extracting said 2D patches from said one or more video bitstreams; and rendering (706), by the client device, the given viewport as a sub-segment of the 3D representation of the scene based on said one or more 2D patches and the related metadata.

Abstract: The embodiments relate to methods for encoding and decoding, and technical equipment for the same. The method for encoding includes obtaining two or more representations of volumetric media content, each of the two or more representations of volumetric media content including multiple media component bitstreams; identifying a relationship between the two or more representations; generating a description file containing a media component description for each media component bitstream; group descriptions grouping the media component descriptions for each media component bitstream; grouping information descriptions providing information on the identified relationship between group descriptions representing representations. The description file is provided to a receiver.

Abstract: An apparatus performs an encoding process including: obtaining a mesh representation of a 3D object; segmenting the mesh representation into 2D projections; reconstructing a 3D mesh from the segmented 2D projections by stitching reconstructed patches, the patches being submeshes of the reconstructed 3D mesh, the stitching performing border fusion based at least on curvature of the patches, to derive parameters for the stitching; and encoding the segmented 2D projections into a bitstream. The apparatus signals the parameters in or along with the bitstream and transmits. An apparatus performing decoding receives the bitstream and signaled parameters, reconstructs a 3D mesh from the segmented 2D projections, and stitches reconstructed submeshes created during the reconstruction together at least as patches, the stitching using the signaled parameters to fuse together pairs of vertices for borders of corresponding patches. The apparatus outputs a modified 3D mesh based at least on the stitching.

Abstract: An apparatus comprising circuitry configured to: receive as input a three-dimensional mesh represented as at least one geometry patch of an atlas and at least one texture patch of the atlas; create an occupancy map that indicates which pixels of the at least one geometry patch and the at least one texture patch are occupied having a valid value; wherein the occupancy map is configured to be used to reconstruct the mesh; enter lossy mode; apply, while in lossy mode, an adaptive smoothing filter algorithm to the occupancy map to discard at least one edge of the occupancy map, and to reduce a bitrate for transmission of the occupancy map; store, while in lossy mode, the adaptively smoothed occupancy map and at least one occupancy filter threshold; and encode the adaptively smoothed occupancy map and the at least one occupancy filter threshold into a bitstream.

Abstract: An apparatus obtains a mesh representation of a 3D object, and performs an encoding process: segmenting the 3D object into 2D projections; encoding the segmented 2D projections into a bitstream; reconstructing a 3D mesh from the segmented and encoded 2D projections; deriving an error vector, describing a shift between 3D data, from patches reconstructed from corresponding encoded patches of the bitstream, and original data in the mesh representation. The patches are submeshes of the reconstructed 3D mesh. The apparatus signals and transmits the error vector in or along with the bitstream. A decoder apparatus receives these and performs a decoding process to form decoded 2D projections of the mesh representation, reconstructs a 3D mesh from decoded 2D projections, applies the patch correction vector elements from the error vector in the decoding process or the reconstructing, produces a modified 3D mesh, as an output mesh and outputs the output mesh.

Abstract: An apparatus comprising circuitry configured to: obtain a three-dimensional model comprising at least one patch, at least one geometry component, at least one occupancy component, and zero or more texture components; subsample the at least one geometry component of the at least one patch of a three-dimensional object at occupied positions using a subsampling criterion; define respective search windows around the respective occupied positions; select respective salient points relative to the respective occupied positions within the respective search windows; triangulate the salient points to approximate a shape of the three-dimensional object; detect zero or more triangles that overlap with at least one unoccupied pixel; split the zero or more triangles that overlap with at least one unoccupied pixel until no triangle overlaps with the unoccupied pixels; and add zero or more additional triangles close to a border of the three-dimensional object to generate a resulting mesh signaled to a decoder.

Abstract: An apparatus comprising circuitry configured to: receive scalability information, the scalability information comprising a number of at least one layer of a three-dimensional object, and at least one sampling rate for the layer; subsample a geometry component of a patch of the three-dimensional object at occupied positions, based on the sampling rate for the layer; define respective search windows around the respective occupied positions; select respective salient points relative to the respective occupied positions within the respective search windows; triangulate the salient points to approximate a shape of a three-dimensional object; detect zero or more triangles that overlap with at least one unoccupied pixel; split the zero or more triangles that overlap with at least one unoccupied pixel until no triangle overlaps with the unoccupied pixels; and add zero or more additional triangles close to a border of the three-dimensional object to generate a resulting mesh for the layer.

Abstract: The embodiments relate to a method for encoding including receiving a sequence of volumetric video frames including a volumetric visual object being defined with a mesh of interconnected vertices; selecting one or more reference frames from the sequence of volumetric video frames for a group of pictures; clustering a mesh of the one or more reference frames into patches, each patch being associated with a corresponding bounding volume; creating matching patches in frames dependent on the reference frame; estimating scaling and rotation parameters for each individual patch in the dependent frame; applying the estimated scaling and rotation parameters to bounding volume of a patch of the dependent frames; packing the patches to an atlas bitstream of a volumetric video stream and including into a bitstream the estimated rotation parameter alongside the bounding volume of a patch. The embodiments also relate to a method for decoding, and corresponding equipment.

Abstract: An example embodiment relates to a method comprising: receiving (700), by a client device, information about a scene associated with a 3D presentation for initiating viewport rendering by an application, wherein said scene is hosted by a server as one or more encoded 2D patches, said 2D patches being projections of the 3D representation of the scene; providing (702) the server with information for selecting 2D patches required to reconstruct at least one segment of the 3D scene as visible in a given viewport; obtaining (704), from the server, one or more video bitstreams generated based on the selected 2D patches and related metadata for extracting said 2D patches from said one or more video bitstreams; and rendering (706), by the client device, the given viewport as a sub-segment of the 3D representation of the scene based on said one or more 2D patches and the related metadata.

Abstract: An apparatus may be configured to: transmit, to a client, an indication of one or more request-response overload capabilities; receive, from the client, at least one request for a plurality of media segments based, at least partially, on the indication of the one or more request-response overload capabilities; and transmit, to the client, at least one response comprising the plurality of media segments. The apparatus may be, for example, a media server, an HTTP overload handler, an edge server, a DANE, etc.

Abstract: An apparatus may be configured to: transmit, to a client, an indication of one or more request-response overload capabilities; receive, from the client, at least one request for a plurality of media segments based, at least partially, on the indication of the one or more request-response overload capabilities; and transmit, to the client, at least one response comprising the plurality of media segments. The apparatus may be, for example, a media server, an HTTP overload handler, an edge server, a DANE, etc.

Abstract: Various embodiments provide an apparatus, a method, and a computer program product. The apparatus includes at least one processor; and at least one non-transitory memory including computer program code; wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to perform: define or utilize file format syntax elements to indicate samples comprising at least one of: one or more description documents, wherein the one or more description documents comprise 3 dimensional information; or one or more updates to at least one description document of the one or more description documents; and define or utilize the file format syntax elements to indicate a relationship between samples containing the one or more description document and update information to the samples.

Abstract: A method comprising: authoring a plurality of sets of media tracks comprising at least a first set of media tracks and a second set of media tracks into a media file format, wherein a subset of tracks of the first set comprises alternate data for each other and a subset of tracks of the second set comprises alternate data for each other; and including, in or along a bitstream comprising a media file including or inferring said media tracks, an indication that said subset of tracks of the first set are alternatives to each other and said subset of tracks of the second set are alternatives to each other upon playback of the media tracks.

Abstract: An apparatus includes at least one processor; and at least one memory including computer program code; wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: obtain a scene comprising three-dimensional information in the form of point clouds, three-dimensional meshes, two-dimensional projections of three-dimensional information, light sources, animations or any other form considered as a representation or description of three-dimensional content; extract lighting information from the obtained scene; process the extracted lighting information into at least one explicit lighting parameter and/or at least one pre-processed lighting map; and encode the scene with the at least one pre-processed lighting map and/or the at least one lighting parameter in a file format or as a visual volumetric video-based coding bitstream.