Overview
ISO/IEC 14496-15:2024 defines how video streams that are structured as Network Abstraction Layer (NAL) units are stored in the ISO Base Media File Format (ISOBMFF). It standardizes sample entries, track structure and metadata for NAL-based codecs such as AVC (ISO/IEC 14496-10) and HEVC (ISO/IEC 23008-2), and includes Annex E mapping for use of sample-entry parameters as the "codecs" MIME parameter per IETF RFC 6381. This seventh-edition International Standard provides the storage semantics needed to carry NAL-unit structured video reliably in MP4/ISOBMFF files.
Key topics and technical requirements
- Sample and configuration definitions: canonical ordering, sample formats and decoder configuration records required to reconstruct access units from stored samples.
- Video track structure: detailed rules for representing NAL-unit streams as ISOBMFF tracks (including AVC, SVC, MVC/MVD variants).
- NAL unit mapping and parameter sets: storage and referencing of parameter sets and NAL unit map entries to support decoder initialization and seeking.
- Timing and composition: handling of decoding time (DTS) and composition time (CTS) and sync/ shadow-sync samples for random access.
- SEI and metadata boxes: definition and syntax for storing SEI messages, SEI manifest, and related signalling within sample entries.
- Sample groups and region/ layering data: support for rectangular region groups, layer information, alternative extraction grouping and picture-region replacement.
- MIME codec signalling: Annex E specifies parameters/sub-parameters for using the sample-entry data in the "codecs" MIME parameter (RFC 6381) for interoperable delivery and identification.
Practical applications
- Packaging and file-based delivery of AVC/HEVC video in MP4/ISOBMFF containers for streaming, download and archival.
- Implementation guidance for packagers, muxers and media creation tools that assemble NAL-based elementary streams into ISOBMFF files.
- Player and decoder vendors: deterministic rules for decoder initialization, seeking and sample extraction from NAL-unit structured tracks.
- Workflow interoperability: ensures consistent handling of parameter sets, SEI metadata and codec signalling across tools and services.
Who should use this standard
- Media packagers, streaming-platform engineers and OTT service providers
- Codec and player implementers (AVC/HEVC toolchains)
- Transcoder and muxer developers, content creators and media archivists
- Standards bodies and system integrators working with ISOBMFF-based delivery
Related standards
- ISO/IEC 14496-10 (AVC/H.264) - codec specification referenced for AVC streams
- ISO/IEC 23008-2 (HEVC/H.265) - codec specification referenced for HEVC streams
- IETF RFC 6381 - MIME type and "codecs" parameter mapping (addressed in Annex E)
Keywords: ISO/IEC 14496-15:2024, NAL unit, ISO base media file format, ISOBMFF, AVC, HEVC, codecs parameter, RFC 6381, SEI, sample entry, video packaging.