1     Definition 2     Functional Requirements 3     Syntax
4     Semantics 5    Conformance Testing 6     Performance Assessment

1      Definition

A Data Type representing the arrangement of the Objects of a Scene that may include Objects and sub-scenes in a hierarchical fashion.

2      Functional Requirements

Scene Geometry may reference Objects and Scenes in a hierarchical fashion.

Scenes may be hierarchical, i.e., they may contain Objects and Scenes.

The following Table gives the Media Type-dependent Scene Geometries.

Scene Geometry name Acronym JSON
3DModel Scene Geometry OSD-3BS Link
Audio Scene Geometry OSD-ABS Link
Audio-Visual Scene Geometry OSD-MBS Link
LiDAR Scene Geometry OSD-LBS Link
Offline Map Scene Geometry OSD-OBS Link
RADAR Scene Geometry OSD-RBS Link
Speech Scene Geometry OSD-SBS Link
Ultrasound Scene Geometry OSD-UBS Link
Visual Basic Geometry OSD-VBS Link

3      Syntax

https://schemas.mpai.community/OSD/V1.3/data/SceneGeometry.json

4      Semantics

Label Size Description
Header N1 Bytes Scene Geometry Header
– Standard-SceneGeometry 9 Bytes The characters “OSD-SCG-V”
– Version N2 Bytes Major version – 1 or 2 characters
– Dot-separator 1 Byte The character “.”
– Subversion N3 Bytes Minor version – 1 or 2 characters
MInstanceID N4 Bytes Identifier of M-Instance.
SceneGeometryID N5 Bytes Identifier of Scene Geometry.
SceneGeometrySpaceTime N6 Bytes Space and Time of Scene Geometry.
ObjectCount N7 Bytes Number of Objects in Scene.
Objects[] N8 Bytes Set of Objects.
– ObjectID N9 Bytes Qualifiers of Object.
– ObjectSpaceTime N10 Bytes Space Time of Object.
SubSceneCount N11 Bytes Number of Sub-Scenes in Scene.
SubScenes[] N12 Bytes Set of Scenes.
– SubSceneID N13 Bytes ID of Sub-Scene.
– SubSceneSpaceTime N14 Bytes Space Time of Sub-Scene.
DescrMetadata N15 Bytes Descriptive Metadata

5     Conformance Testing

A Data instance Conforms with Scene Geometry (OSD-SCG) V1.3 if:

  1. The Data validates against the Visual Scene Geometry’s JSON Schema.
  2. All Data in the  Visual Scene Geometry’s JSON Schema
    1. Have the specified type
    2. Validate against their JSON Schemas
    3. Conform with their Data Qualifiers.

6     Performance Assessment