Overview
ISO/IEC 29341-20-10:2017 - Audio video transport service (AVTransport) - defines the UPnP Device Architecture Level 4 service for controlling the transport of audio and video streams. Compliant with UPnP Device Architecture v1.0, this standard specifies a common A/V transport control model and a set of state variables and actions to manage playback, seeking, playlists, synchronization and metadata retrieval for a wide range of media devices (disc, tape, solid‑state, tuners and streaming endpoints). Note: the service does not provide scheduled recording.
Key topics and technical requirements
- Service model and state variables: Defines transport-centric state variables such as TransportState, TransportStatus, AVTransportURI, CurrentTrackMetaData, RelativeTimePosition, LastChange, SyncOffset, and many A_ARG_TYPE data types used for arguments.
- Actions (control API): Standardized actions include SetAVTransportURI(), SetNextAVTransportURI(), GetMediaInfo(), GetTransportInfo(), GetPositionInfo(), Play(), Pause(), Stop(), Seek(), Next(), Previous(), SetPlayMode(), Record(), SyncPlay()/SyncStop()/SyncPause(), SetPlaylist and playlist management actions.
- Eventing and moderation: Event model for state updates, including the LastChange eventing mechanism to notify control points of state changes.
- XML service description & testing: Includes the XML description schema for service exposure and conformance tests.
- Protocol-specific guidance: Annexes describe protocol-specific behavior and implementation notes for HTTP streaming, RTSP/RTP/UDP, IEC61883, internal streaming and vendor-specific streaming.
- Theory of operation: Informative annex explains transport abstraction, playlist handling, multi-instance transports and CLOCKSYNC synchronized playback.
Practical applications and who uses it
- Device manufacturers: Implement AVTransport in smart TVs, networked Blu‑ray players, media players, set‑top boxes, networked speakers and AV receivers to provide consistent remote-control and playback behavior.
- Firmware & software developers: Integrate UPnP AV control stacks, implement transport actions/state variables, and ensure eventing/compliance.
- System integrators and home automation: Use AVTransport to orchestrate multi-room playback, synchronized playback (CLOCKSYNC), and playlist control across devices.
- Test engineers & QA: Validate UPnP AV compliance using the service’s test descriptions and XML service definitions.
- Streaming platform integrators: Map AVTransport semantics to HTTP/RTSP or vendor streaming protocols per the annex guidance.
Related standards
- UPnP Device Architecture v1.0 (base specification)
- UPnP AV services such as ConnectionManager (A/V connection setup) and ContentDirectory (media metadata)
- Other parts of the ISO/IEC 29341 series covering device and service definitions
Keywords: ISO/IEC 29341-20-10:2017, UPnP, AVTransport, audio video transport service, UPnP Device Architecture, AVTransportURI, streaming control, CLOCKSYNC, ContentDirectory, ConnectionManager.