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Definition Functional Requirements Syntax Semantics Conformance Testing Performance Assessment

1      Definition

Scene Descriptors are a Data Type including the Objects of a scene, their Sub-Scenes, and their arrangement in the Scene. Scene Descriptors may be hierarchical, i.e., they may contain Objects and Scene Descriptors.

2      Functional Requirements

A Scene Descriptors instance must include:

  1. The Scene Descriptors Header

  2. The ID of the Scene Descriptors instance.

  3. The ID of the Objects in the Scene.

  4. The ID of the Sub-Scenes in the Scene.

  5. The Space-Time information of the Objects and Sub-Scenes in the Scene.

A Scene Descriptors instance may include:

  1. The ID of a virtual Space (M-Instance) where it is or it is intended to be located.

  2. The ID of a U-Environment where it is or it is intended to be located.

  3. The Space-Time information of the Scene.

  4. Information about this Scene Descriptors instance.

  5. Descriptive Metadata.

3      Syntax

https://schemas.mpai.community/OSD/V1.5/data/lSceneDescriptors.json

4      Semantics

Label

Description

Header

Scene Descriptors Header – Standard “OSD-SCD-Vx.y”

MInstanceID

Identifier of the M-Instance.

UEnvironmentID

Identifier of the U-Environment.

3DModelSceneDescriptorsID

ID of this Scene Descriptors instance instance.

3DModelSceneDescriptorsTime

Space and Time of this Scene Descriptors instance.

3DModelObjectCount

Number of Objects in Scene.

3DModelSubSceneCount

Number of Sub-Scenes in Scene.

3DModelSceneDescriptorsSpaceTime

Space and Time of Scene Descriptors instance.

3DModelSceneObjects[]

Set of Data related to Objects in the Scene.

– Basic3DModelSceneObjectSpaceTime

Space and Time of Object in the Scene.

– Basic3DModelSceneObject

Basic Object in the Scene.

3DModelSubScenes[]

Set of Data related to Sub-Scenes in the Scene.

– Basic3DModelSubSceneSpaceTime

Space and Time of Object in the Scene.

DataXMData

Information on this Scene Descriptors instance.

DescrMetadata

Descriptive Metadata

5     Conformance Testing

A Data instance Conforms with Scene Descriptors (OSD-SCD) if:

  1. Its JSON Object validates against its JSON Schema.
  2. Any included  JSON Object validates against its JSON Schema.
  3. All Data in the JSON Object:
    1. Have the specified Data Types.
    2. Conform with the Qualifiers signaled in their JSON Schemas.

6     Performance Assessment