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Core Object Model

Containers​

A Container MUST contain:

  • one or more Streams
  • MAY contain Events
  • MAY contain Metadata objects

ASCII diagram:

Container
 ├── Streams[]
 │     └── Samples[]
 ├── Events[]
 └── Metadata[]

Streams​

A Stream MUST:

  • declare exactly one Modality
  • contain ordered Samples
  • include a unique stream_id

ASCII visualization:

Stream (SkeletalPose)
  Sample 0 ── t=33.1ms
  Sample 1 ── t=50.3ms
  Sample 2 ── t=66.6ms

Samples​

Each Sample MUST include:

  • at least one timestamp
  • payload matching the Modality schema

Example:

{
  "timestamp": { "t_system": 38932922 },
  "joints": [...]
}

Events​

Events live at the Container level.

ASCII:

EventPoint("left-hand-grasp-start")
   timestamp → 103.2ms
   refs → [left_hand_pose_stream]

Cross-References​

All references MUST resolve strictly.

Timeline Policy​

No global timeline policy required.

Invariants​

  • Streams carry one modality.
  • Samples always have timestamps.
  • Events live at container-level.
  • All references resolve strictly.