ISO/IEC 23008-2:2023

Overview

ISO/IEC 23008-2:2023 - published by ISO/IEC - specifies High Efficiency Video Coding (HEVC) as Part 2 of the multipart standard “Information technology - High efficiency coding and media delivery in heterogeneous environments.” The fifth edition (2023) defines bitstream formats, syntax and semantics, decoding and parsing processes, and normative annexes for profiles, tiers and levels, multi-layer, multiview, scalable and 3D extensions. This standard is the authoritative reference for implementing HEVC-compliant encoders, decoders and transport workflows.

Key topics and technical requirements

The standard covers comprehensive technical building blocks and normative requirements, including:

• Bitstream and picture formats: NAL unit formats, raw byte sequence payloads, byte alignment, and picture/CTU/CTB partitioning (tiles, slices, slice segments).
• Syntax and semantics: Tabular specification of syntax elements, profile/tier/level signaling, scaling lists, and supplemental enhancement information (SEI).
• Prediction and transform: Intra and inter prediction modes, quadtree/block partitioning, residual coding and transform processes.
• In-loop filtering: Deblocking filter and Sample Adaptive Offset (SAO) requirements for decoded-picture quality.
• Parsing and entropy coding: Exp-Golomb coding, CABAC parsing, binarization and arithmetic encoding/decoding processes.
• Decoding process: Detailed stepwise decoding, reference picture handling, picture order count and unavailable-reference derivations.
• Auxiliary functions: Sub-bitstream extraction, hypothetical reference decoder (HRD), byte-stream format, Video Usability Information (VUI) and SEI messages.
• Normative annexes: Profiles/tiers/levels, byte stream, multi-layer common specs, multiview HEVC, scalable HEVC and 3D HEVC.

Practical applications

ISO/IEC 23008-2:2023 is intended for real-world video technology implementations and media delivery systems:

• Video codec development: Reference for implementing compliant HEVC encoders and decoders (software or hardware).
• Streaming and OTT services: Ensures interoperable bitstreams for adaptive streaming, broadcasting and CDN workflows.
• Consumer electronics: Firmware and SoC developers for TVs, set-top boxes, mobile devices and cameras.
• Professional media: Broadcast, contribution links, and transcoding services that require standardized bitstream handling.
• Advanced use cases: Multiview/3D video, scalable / multi-layer encoding, VR/AR and immersive media delivery.

Who should use this standard

• Codec engineers and firmware developers
• Streaming platform architects and CDN engineers
• Broadcasters and content delivery integrators
• Test labs and conformance officers
• R&D teams in video compression and multimedia systems

Related standards

• Other parts of ISO/IEC 23008 (media delivery and system-related parts)
• Standards for container formats and streaming (e.g., ISO base media file format, DASH) - used together with HEVC bitstreams in delivery systems

Keywords: ISO/IEC 23008-2:2023, High Efficiency Video Coding, HEVC, bitstream, NAL unit, CABAC, profiles tiers levels, multiview, scalable, 3D, video codec standard.