SC-03-07 meeting, San Francisco, 2004-10

Report of the meeting of SC-03-07 working group (formerly SC-06-06) on Audio Metadata of the SC-03 subcommittee on Network and File Transfer of Audio held in San Francisco, CA., US., 2004-10-28.

The meeting was convened by chair C. Chambers

The agenda and the report of the previous meeting held in Berlin, Germany 2004-05-08 were accepted as written.

Development projects.

AES-X114: Metadata review.
This project's key purpose is to review metadata work across the AES and other professional bodies.

It was reported that the SMPTE metadata dictionary document has been offered to the IEC. This provides a reference to the detailed dictionary maintained by the SMPTE. A discussion on how the AES would feed any additional items into the SMPTE dictionary. It was agreed that it would be of great benefit if the AES could set up a process for a formal method to allow any additional AES dictionary requirements to be added as ad when required. The group will study this further but it was noted that the SMPTE registry web site has a class 13 registered for public use that possibly the AES could use to register its requirements with the SMPTE dictionary.

The work of task group AES-X111 (UMID insertion into the AES3 stream) being carried out within working group SC-02-02. This task group has completed its work and its output documents is close to completion. From a metadata point of view, this work will produce a key link between live audio streams and the metadata associated with these streams until such metadata is "wrapped" with the audio in file based structures like BWAV, AAF or MXF.

The discussions held within the SC-02-02 mail reflector were summarised by the chair. These centred around the need to be able to embed different types of identifier depending on the business use of that stream. As an example, does the identifier need to uniquely identify the audio content such as a contribution from a concert or does the identifier need to identify a stream to air where the content changes? In these two examples a different identifier seems appropriate such as a UMID in the first instants and a UUID in the second. In the second instants it would be the UUID plus the schedule data that could be used to uniquely identify the content against time. The AES-X111 proposal is being modified to allow the use of a number of different identifying schemes.

The chair asked for suggestions for any additional ID schemes that could be included in the AES-X111 work such as the TV Anytime "Content Reference Identifier" (CRID) for example.

Shigeru Aoki presented some of the issues surrounding identifiers in the TV Anytime project.

Version 8 of the SMPTE dictionary (as an XL document) is available at: This link was also sent out on the e-mail reflector at the time of this meeting. The chair recommended that members of the group look through the audio sections of this for discussion at our next meeting.

The meeting then went on to discuss the work going on in the EBU to describe "middleware" and its use in system integration. The meting was shown a draft version of the report that will be published by the EBU early in 2005. The chair described the format of the report and the work that has been done to develop this and a discussion started on the issues raised. It is hoped the full EBU report will be available to the AES well before the next meeting of this group. (Post meeting: This report was published February 2005 and is freely available in two parts as Tech 3300 and Tech 3300s from: Please download this and use within your organisations as needed.)

AES-X134: Core audio metadata XML definitions.
The goal of this task group is to produce a number of metadata "sub sets" for specific tasks, and map these sets to the administrator and audio schemas being produced in SC-03-06 that could be considered as defining the metadata "super-set".

A task group meeting was held in Berlin. There were two schemas presented to the meeting, one from NRK, Norway and one from Tokyo FM Broadcasting. Shigeru Aoki agreed to talk to NRK to agree how this work could be progressed.

ITU study group 6 has had an update on current work on metadata definitions that has been produced by Japan. The documents from this update will be submitted to the FTP site when they are available following the ITU meeting next week.

The meeting agreed that AES-X134 should concentrate on the use of XML documents and schemas to develop and define professional audio metadata sub-sets and mapped to current administrator metadata. This work should not reinvent the administrator metadata already produced in SC-03-06 but should identify and add those items considered to be required for professional audio exchange that do not currently exist. The question of how any document produced by this group was to be published was discussed? I was suggested that the AES should produce a glossary of terms (attributes) as well as set up a web server schema reference site (at a fixed URI) where any AES schema can be validated on the web.

It was suggested that it would be possible to set up a fixed URI and a number of examples of glossaries will be studied with a view to implement an AES method for publishing XML schemas.

AES-XP138: IFPI Liaison.
Nothing further to report.


There is a liaison in SC-06-01 with the SMPTE registration authority, which the standards secretary felt should be assigned to SC-03-06 or SC-03-07. To be decided.

New Projects

There were no new projects

New Business

There was no new business.

The next meeting will be scheduled in Barcelona in conjunction with the AES 118th Convention in Barcelona, Spain, 2005-05.

AES - Audio Engineering Society