Overview - What ISO/IEC 23001-4:2017 covers
ISO/IEC 23001-4:2017 specifies methods and general principles for representing codec configurations within the MPEG Reconfigurable Video Coding (RVC) framework. The standard focuses on describing a decoder configuration as two complementary parts: a Functional Unit Network Description (FND) and a Bitstream Syntax Description (BSD). It normatively defines the XML-based languages used in RVC: FNL (Functional Unit Network Language) for network topology and RVC‑BSDL (a pertinent subset/extension of BSDL from ISO/IEC 23001‑5) for bitstream parsing. The document also includes the normative specification of RVC‑CAL for FU behaviour and informative annexes on MP4 storage, RTP carriage and middleware relations.
Key technical topics and requirements
- Decoder Description (DD): A complete DD is composed of the FND (connectivity of FUs) and BSD (implicit parsing rules and tables) to fully specify an Abstract Decoder Model (ADM).
- FNL (Functional Unit Network Language): Normative XML dialect to describe networks of Functional Units (FUs) and their connections (ports, links).
- RVC‑BSDL (Bitstream Syntax Description): A subset/extension of ISO/IEC 23001‑5 BSDL tailored for RVC; used to describe bitstream syntax and parser behaviour.
- RVC‑CAL: Dataflow-oriented language for specifying FU behaviour; provided normatively to define I/O behaviour of FUs.
- Model instantiation: Procedures to build the ADM from the DD and the MPEG video tool library (ISO/IEC 23002‑4); the ADM is normative in behavior (I/O semantics).
- Normative/informative annexes: Annexes include FNL examples, RVC‑BSDL specification, RVC‑CAL details, MP4 storage (Annex G), RTP carriage (Annex H), bitstream parser guidance (Annex I), and middleware relation (Annex J).
Practical applications and who uses it
ISO/IEC 23001-4 is intended for:
- Codec architects and implementers building reconfigurable video decoders or tool libraries.
- MPEG tool library developers who supply Functional Units and VTL components.
- Multimedia system integrators who need to store or carry decoder configuration (e.g., in MP4 or RTP).
- Middleware and standards engineers integrating codec configuration with multimedia middleware (M3W).
Practical uses include describing and exchanging decoder configurations, instantiating normative ADMs for testing, enabling interoperable decoder implementations, and supporting bitstream parsing generation tools.
Related standards
- ISO/IEC 23001‑5 - Bitstream Syntax Description Language (BSDL)
- ISO/IEC 23002‑4 - MPEG video tool library (video coding tools)
- ISO/IEC 14496‑12 (MP4) - Base media file format (storage linkage)
- IETF RTP/SDP (for carriage/transport considerations)
Keywords: ISO/IEC 23001-4:2017, RVC, codec configuration representation, FNL, RVC‑BSDL, RVC‑CAL, bitstream syntax description, functional unit network, MPEG video tool library, decoder description.
Open preview (PDF)Information technology — MPEG systems technologies — Part 4: Codec configuration representation