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Mix Magazine

This installment of The Bitstream column appeared in the July 2001 issue of Mix Magazine.

The Bitstream

This column discusses discusses the tribulations of audio project transfer…

Get Up Off’a That Thang

I’ve just returned from yet another NAB convention and, boy, am I sick of Vegas. I was shopping, among other things, for DAWs for one of my clients. This quest brought home the fact that there’s very little interoperability amongst vendor’s systems, except at the most basic level. What’s up with that?

This month, I’m taking aim at Our Illustrious Engineering Society, the DAW vendors and you, the Bubba that writes a check for gear that can’t play with the kids next door.

Now, before I go off, I’d like to thank the few vendors, such as Studio Audio & Video Ltd., that actually deliver what other dweebs promise. The SADiE boys have been the standard bearers of interoperability, handling disparate sound and EDL file formats effortlessly, something few other vendors can demonstrate. So, what about other vendor’s handling of project and session level file exchange? Hah! Few have a lock on that capability because, “Ye just can’t do it, laddie!”

OK, I’m being reactionary…(and exaggerating even). If you’ve followed my past rants, you know I like interoperability among heterogeneous products. It means you can buy just the right tool for your job. At present, it’s difficult or impossible to move complete projects from one DAW environment to another while retaining complex fades, plug–in state and other aspects of the process. Digital automation is to blame for this increasing lack of standards and only your loud and persistent screams of protest, as well as the ceremonial Withholding Of The Checkbook, will move vendors to adopt the meagre standards we have available.

What are these standards? You got two: AES31-3-1999 and MPEG-7. The AES31 standard began life way back in 1997 to provide “…a convention for expressing edit data in text form in a manner that enables simple and accurate computer parsing while retaining human readability.” Sounds familiar? AES31 is basically an improved version of the old CMX EDL interchange format, with such modern features as rudimentary nonlinear fade shape definitions and an assumption that BWAV on FAT32 is the de facto sound file format. You too can spend $40 for an illegible copy of the spec, if you’re highly motivated.

AES31 has support from iZ, Euphonics and Waveframe. The AES, as part of this unification effort, also has several initiatives slated for standardization. One is cross–compatibility between AES31 and AAF, including meetings at the aforementioned NAB. More on AAF later but the AES has more work ongoing:

• AES-X66, a file format for transferring digital audio data between systems of different type and manufacture

• AES-X68, a format for passing edited digital audio between systems of different type and manufacture that is based on object oriented computer techniques

• AES-X69, an interchange format for digital audio file transport

These projects are slated for completion in a one to three year time frame. Hello? How long have we suffered with OMF, the laughing stock of interchange “standards?”

We can thank Avid for providing OMF, a nonstandard “standard” that not even Avid itself fully supports. However with enough sweat, swearing, prayer beads, and a very cooperative video editing colleague, you can make an OMF work flow actually work! As an industry wag recently observed, “You know you’re in trouble when you have to write a program to unify a “standard” file type!” DSP Media has come to the rescue with just such a program. Their AVtransfer utility, the Rosetta Stone of project file translation, does all of the heavy lifting for OMF conversion and they plan to add many more formats as the product matures.

Back to AAF for a moment. Microsoft, along with Adobe, Matrox, Avid/Softimage, Pinnacle Systems/Truevision and Sonic Foundry proffered the Advanced Authoring Format (AAF) which provides file interchange for content creation and authoring tools. Me–too acceptance from Sonic Solutions and Sony means it’s sure to live in the hearts of corporate spin doctors for years to come while we continue to flail in want of a real solution. I dropped in on the AAF home page at the time of writing and found only a bunch of dead links, indicative of AAF’s true level of importance in the grand scheme of things.

Microsoft, as the founder of the Multimedia Task Force, hopes to promote the AAF format, along with ASF (Advanced Streaming Format), as an industry standard. In other words, they have an old format, AVI, that needs replacing so they’ve created yet another proposed standard “…tuned to the needs of the production community.” AAF is based largely on OMIF (Open Media Interchange Format), thus guaranteeing it’s lack of interoperability on any platform not controlled by the member interests. As mentioned earlier, the task force is promoting both ASF and AAF to standards bodies, including the SMPTE* and the AES.

And now, on to MPEG-7…Let’s start by quoting the MPEG-7 home page, “In October 1996, MPEG (Moving Picture Experts Group) started a new work item to provide a solution for the urging problem of generally recognized descriptions for audio-visual content, which extend the limited capabilities of proprietary solutions in identifying content that exist today. The new member of the MPEG family is called ‘Multimedia Content Description Interface,’ or in short MPEG-7.” MPEG-7 is concerned with creating a set of description schemes and descriptors alone with a language to specify those schemes and a framework for coding that description. In a word, metadata. Metadata describing multimedia content. MPEG-7 will attempt to standardize the interchange of data essence, as the SMPTE calls payload, by allowing disparate systems to grok each others data types. Who will benefit from this far reaching vision? Most everyone in electronic content creation, management and delivery, that’s who. But only if we follow recommended standards.

What’s the difference between the audio and video production communities? The audio guys are too complacent to follow recommended practices. Remember XLR pin assigns? Adhering to a standard makes for shorter work days for the operator and happy customers for the vendor. The SMPTE has created an Engineering Committee on Wrappers and Metadata. Their coding scheme and metadata dictionary have been submitted in MPEG-7 as a Description Scheme. This work, characteristic of SMPTE’s knack for bringing about industry consensus, is important today and especially tomorrow. Come on AES, apply some persuasion! I beseech all AES members and DAW manufacturers to get up off your good intentions and support and promote, not vendor–driven initiatives such as AAF, but open industry standards exemplified by AES31 and MPEG-7. Now where’s my bulletproof vest…

* — For more info on lobbying standards bodies, see the April 2000 Bitstream

Bio - OMas prefers the trenches to the hilltops when it comes to day–to–day work and the mountain tops to the valley when it’s time to play. This column was created while under the influence of OS X and McCoy Tyner’s new SACD recording with Stanley Clarke on Telarc.