Guidelines: Embedded Metadata in Broadcast WAVE Files
Audio-Visual Working Group
Embedded metadata can travel with a digital object during its life cycle and often exists in synergy with metadata in an organization's databases or other information technology systems. Embedded metadata enables people in and outside an organization to work more efficiently, provides valuable data to the systems that preserve digital content, and can assist in disaster recovery. In addition to these guidelines for WAVE files, FADGI offers two embedding guidelines for still images: for minimal descriptive metadata and for the TIFF header. Meanwhile, regarding WAVE file embedding, the Working Group has developed the BWF MetaEdit tool to support users.
Specification: Current and Earlier Versions
These guidelines pertain to metadata to be embedded in Broadcast WAVE files. They emphasize the importance of identifying the responsible organization and providing one or more item identifiers, as well a providing other guidance. The guidelines recommend an implementation of the bext chunk standardized by the European Broadcast Union (EBU) in EBU-TECH 3285: Specification of the Broadcast Wave Format Version 2 (2011) and of the INFO-list chunk defined in the Microsoft-IBM RIFF specification (1991).
Broadcast WAVE Metadata Embedding Guidelines, Version 2 (PDF, 343 KB)
Approved by Working Group - April 23, 2012.
Broadcast WAVE Metadata Embedding Guidelines, Version 1 (PDF, 274 KB)
Approved by Working Group on September 15, 2009, and superceded by version 2 on April 23, 2012.
Three background documents provide an explanatory context for the guidelines and describe the constraints imposed by existing WAVE metadata structures. The documents discuss a variety of metadata chunks in WAVE files: the bext and INFO-list chunks covered by the guidelines, as well as the format chunk with its technical metadata, and the aXML and iXML chunks. The introductory document describes the loudness metadata introduced in version 2 of the EBU Broadcast WAVE standard and the Working Group's provisional implementation of an ad hoc MD5 chunk for checksum (hash value) data. The third document provides information about the types of identifiers used in some federal agencies.
- Introductory Discussion (PDF, 295 KB) for the proposed audio metadata embedding guidelines (revised 2012)
- Consultant’s report on embedding options (PDF, 319 KB) in digital audio files (2009)
- Identifiers: Types and Characteristics (PDF, 42 KB) relevant to digital content entities, including audio files (2011)
BWF MetaEdit: About the tool
BWF MetaEdit (at SourceForge) is a free, open source tool that supports embedding, validating, and exporting of metadata in Broadcast WAVE Format (BWF) files, including support for the Federal Agencies guideline presented above. BWF MetaEdit was developed by the Federal Agencies Digitization Guidelines Initiative, supported by AudioVisual Preservation Solutions. The newest version of BWF MetaEdit (1.2.0) conforms the tool to version 2 of EBU-TECH 3285: Specification of the Broadcast Wave Format (May 2011).
Features include the ability to:
- Import, edit, embed, and export specified metadata elements in WAVE audio files
- Export technical metadata from Format Chunks and minimal metadata from bext and INFO chunks as comma-separated values and/or XML, across a set of files or from individual files
- Evaluate, verify and embed MD5 checksums, as applied to the WAVE file's data chunk (audio bitstream only) into a non-standardized, ad hoc "MD5 chunk."
- Enforce the guideline (above) developed by the Federal Agencies Audio-Visual Working Group, as well as specifications from the European Broadcasting Union (EBU), Microsoft, and IBM
- Report certain errors in the construction of WAVE files
- Choose from Command line and GUI, for Windows/PC, Macintosh OS, Linux; see list of options at SourceForge
BWF MetaEdit: User's Guide and Link to SourceForge
- BWF MetaEdit help resource, which serves as a user's guide.
- BWF MetaEdit application at SourceForge.
Provide Comments on the Specification or Tool
Use the online form to submit your comments.
Last Updated: 01/09/2013