SC-02-08 meeting, online, 2020-05

Report of the meeting of the SC-02-08 Working Group on audio file transfer and exchange of the SC-02 Subcommittee on Digital Audio, held online, 2020-05-26.

The meeting was convened remotely by Piotr Majdak.

The formal notice on patent policy was read.

The agenda and the report of the previous meeting, held in New York, NY, USA 2019-10-17 were approved as written.

In attendence were P Majdak, F Zotter, U Henry, P Treleaven, R Kessler, S Norcross, J Ahrens, J De Muynke, M Noisternig, A Farina, S Kramer, B McCoy, B Olson, R Cabot.

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

Open Projects

AES31-3-R Review of AES31-3-2008 (r2013), AES standard for network and file transfer of audio - Audio-file transfer and exchange - Part 3: Simple project interchange. including maintenance of annex F.
The amendment to AES31-3 was discussed. This includes a revised annex F that specifies a SMPTE Universal Label to be used in clause "ADL version header" to identify an audio decision list (ADL).

We received a Node in the metadata dictionary for 'File exchange metadata defined in AES standards'. This means that further file-exchange labels can be generated more easily in the future. The group discussed the idea that if the AES issues multiple unique labels under the AES Class 13 registration in different documents that we should provide a dictionary of the issued labels and post it on the AES Standards web site.

AES69-R Review of AES69-2015: AES standard for file exchange - Spatial acoustic data file format
The document needs to be revised this year. The chair had requested submissions for inclusion. He explained the collected issues:

There is a need to store headphone related data. The SimpleHeadphoneIR conventions are stable and already in-use conventions for headphone IR measurement data. It is planned to add this as an Annex.

There is a need to store information on filter transfer functions expressed as second order sections. The chair described a proposed and already in-use data type for filter representation which they plan to include in another annex.

There is a need for an extension that handles spatially continuous directivity representations (as opposed to ones which are described at specific directions.)

There is a need for methods to describe free-field directivity as when characterizing instruments and singers. It is important to avoid overlap with the ddirectivity representation above.

There is also a need for multi-perspective data that can handle multiple source and listener positions.


AES-X236 - IEC 62942 liaison, Broadcast Wave Format file
AES31-2 was published as an IEC standard for broadcast wave format file, with addition of optional UBXT chunk to carry international character sets.

New Business
The group agreed to meet biweekly, starting with 9th June 2020.

New projects

No new projects were proposed.

The next meeting will be held in Vienna, Austria 2020-05, in conjunction with the AES 148th convention.

AES - Audio Engineering Society