ISO/IEC 15938-3:2002

Overview

ISO/IEC 15938-3:2002 is Part 3 of the ISO/IEC 15938 series (commonly known as MPEG-7) and defines the visual component of the Multimedia Content Description Interface. It standardizes a set of descriptors, description schemes (DS) and datatypes for describing visual features of multimedia content (still images, video and 3D models). Each tool in the document is specified by a DDL (Description Definition Language) syntax, a normative binary syntax, and precise semantic definitions to ensure interoperable metadata exchange.

Key topics

• Visual description tools organized by feature groups: basic structures and containers, color, texture, shape, motion, and localization.
• Descriptor structure: every descriptor/DS includes normative Syntax, Binary Syntax, and Semantic subclauses.
• Basic primitives: grid layout, temporal interpolation, spatial coordinates, multiple-view and time-series containers.
• Color tools: color space, quantization, dominant/scalable color, color layout, color structure, GoF/GoP color descriptors.
• Texture tools: homogeneous texture, texture browsing, edge histogram descriptors.
• Shape tools: region shape, contour shape, 3D shape descriptors.
• Motion tools: camera motion, motion trajectory, parametric motion, motion activity.
• Localization tools: region locator and spatio-temporal locator for precise content positioning.
• Annexes: normative basis functions for face recognition and binary representation of media-time tools; informative patent statements.

Applications

ISO/IEC 15938-3 provides standardized metadata building blocks for:

• Content-based image and video retrieval (visual search and indexing).
• Multimedia asset management and cataloging for archives and broadcasters.
• Automated analysis: feature extraction for indexing, summarization, and scene understanding.
• Interoperable exchange of visual metadata between tools, players, and delivery systems.
• Research and development in computer vision, multimedia retrieval and metadata tooling.

Who benefits: metadata engineers, multimedia software developers, video search platform designers, broadcasters, digital-asset managers, and standards implementers who need a formal, interoperable way to describe visual content.

Related standards

• ISO/IEC 15938 (MPEG-7) family:
  • Part 1: Systems
  • Part 2: Description Definition Language (DDL)
  • Part 4: Audio
  • Part 5: Multimedia description schemes
  • Part 6–8: Reference software, conformance testing, extraction/use guidelines

Keywords: ISO/IEC 15938-3, MPEG-7 Visual, multimedia metadata, visual descriptors, DDL, binary syntax, color descriptors, texture descriptors, motion descriptors, localization.