ISO/IEC 15938-1:2002/Amd 2:2006 PDF

Overview

ISO/IEC 15938-1:2002/Amd 2:2006 - Information technology - Multimedia content description interface - Part 1: Systems - Amendment 2: Fast access extension - extends the Part 1 Systems specification to add an optional indexing layer for BiM-encoded multimedia description streams. The amendment defines index concepts, data structures and decoder initialization elements that enable fast, random access to Binary MPEG-7 (BiM) fragments (FUU’s) by querying for XML nodes and related node values.

Key topics and technical requirements

• Index architecture: Index is split into a Path Index (locates relevant Value Index) and a Value Index (maps indexed values to BiM stream references). Value Indexes can be partitioned into Value Sub-index structures to support large data sets.
• Index components and formats: Defines terms such as Index Access Unit, index stream, IndexDecoderInit, index access unit header, BiM stream reference (local/remote), data repository reference, and node reference.
• Query model: Supports multi-criteria queries using a PathIndexKey (context path plus relative paths to related nodes). Allows equality and range-based searches and combinations of multiple conditions.
• Indexing strategies:
  • Multi-value indexing (composite value or hierarchical single-value) - optimized for compact index size and minimal comparisons.
  • Multi-stage indexing - segments index stream for caching and constrained client resources; facilitates staged acquisition and search.
• Decoder/initialization: Requires acquiring the BiM DecoderInit and the IndexDecoderInit before querying an index stream; introduces flags and a ContextPathTable mechanism (ContextPathTableFlag, ContextPathCode_Length, etc.).
• Addressing: Adds a fixed length context path option (ContextPathTable) for simplified node addressing where limited node addressing suffices.
• Data structures: Supports BTree-like structures, position codes, and defined encodings for path and value keys.

Applications and who uses this standard

• Device manufacturers and terminal implementers who need efficient selective retrieval of multimedia metadata fragments from BiM streams.
• Content providers and streaming services offering fine-grained metadata access (e.g., locate media fragments by attribute values).
• Middleware and indexing engine developers implementing client-side caching, staged index acquisition, and multi-criteria search over multimedia descriptions.
• System architects designing delivery layers that must balance index size, access latency, and client resource constraints.

Related standards

• Part of the ISO/IEC 15938 series (the multimedia content description interface family). Implementers should consult other Parts of ISO/IEC 15938 and the main Part 1 Systems text for complete BiM stream and DecoderInit definitions.

Keywords: ISO/IEC 15938-1:2002/Amd 2:2006, Fast access extension, indexing, BiM stream, PathIndexKey, Value Index, Index Access Unit, IndexDecoderInit, multimedia metadata indexing.