SC-07-01 meeting, Budapest, 2012-04

Report of the meeting of the SC-07-01 Working group on Audio Metadata held in Budapest, Hungary, 2012-04-27.

The meeting was convened by chair C. Chambers.

The agenda and the report of the previous meeting, held on 2011-10-22 were accepted as written.

Projects assigned to this group but not mentioned here had no action requested or required - see for details.

Open Projects:

AES57-R Review of AES57-2011, AES standard for audio object structures for preservation and restoration
The revision of AES57 was discussed with reference to details received very late in the period just prior to the publishing of AES57 which included the addition of "layertype" for layer on optical disk "datatype". This addition could be added for tape as well to provide a way to handle the description of leader tape when needed.

Revision will be carried forward to the next meeting in order to allow any further items to be included, in particular from those proposing to implement the standard in the near future.

AES60-R Review of AES60-2011, AES standard for audio metadata - Core audio metadata.
It was agreed to hold this review until the next meeting where version 1.4 of EBU Tech 2393 is expected to have been published. It was also agreed that worked examples of common uses of AES60 would be developed with a view to publishing these as AES information documents.

Development Projects:

AES-X071 Liaison with SMPTE Registration authority.
No specific items were raised at this meeting beyond noting the considerable effort of J.P. Evain from the EBU, in registering Tech 2393 with the SMPTE's metadata dictionary. This will result in AES60 not having to go through this process.

AES-X098C Administrative metadata for audio objects - Process history schema
scope: To collect information on all metadata issues pertaining to digital audio objects and all aspects of the digital documentation of digital audio objects. This scope includes field structures to describe and provide access to the audio content contained in digital files. It includes transfer, preservation and restoration information.

The latest update on the working-group document site was produced following the discussions and comments received at the previous meeting in New York. This latest draft was looked through with the only comment being that there seemed to be a very large number of content and clause levels. It was agreed that this would be studied to establish if there was any workable method of reducing these without degrading the content relationships. D. Ackerman reported he will have a finished draft complete by the next meeting.

AES-X144 Metadata Review
Scope: To study and report on the methods and techniques for attaching and implementing metadata through all aspects of interfacing real-time and file-transfer audio, including, where related to audio, other metadata related to other media. The scope includes metadata for professional recording, sound reinforcement, production, broadcasting and transmission as well as exchange of metadata and associated audio among different organizations. It includes the development of techniques, such as UML, to aid the description of the relationships and flow of metadata requirements in an open and recognised way.

The addition of loudness metadata to existing standards was discussed. In particular, the most suitable location for such data when items a placed into archives. It was agreed that its inclusion in the Broadcast Wave Format (BWF) structure should be sufficient. However, it was suggested that such data could also be included in AES60 if absolutely necessary.

No other items were raised under this project.

AES-X155 AES standard for audio metadata - Production recording metadata set (iXML)
The policy on the text case of the original Institute of Professional Sound XML input document, which was all in upper case, was agreed. As XML is case sensitive, contrary to the input document assertion, it was agreed that the schema would be written in lower case with all the attribute names in uppercase to cater for existing implementations of iXML and ensure compatibility. This can be seen clearly in the PDF print of the schema in the working-group document site as file iXML_schema_printv2b_120428.pdf.

T. Vaervagen has produced a draft schema for AES-X155 and the chairman had produced a second version of this following some erroneous text insertions that had somehow found their way into the file. This version is on the FTP site along with a grid printout that was shown at the meeting as a PDF file. Tormod has agreed to put the finishing touches to this schema and resubmit this to the groups document area as soon as possible.

It was agreed that a secretarial draft will be produced during the summer so this could be posted in good time before the San Francisco meeting in October with a target of getting this to CFC by the end of the year. From previous meetings it was noted that the clause on speed was confusing and Annex E should have further examples added to clarify the differences from those in clause 5.31.


There were no liaison issues.

New Projects:

There were no new projects.

New business:

There was no new business.

The next meeting will be scheduled in conjunction with the AES 133rd Convention in San Francisco, CA, US, October, 2012.

AES - Audio Engineering Society