Taking MXF Interoperability to the Next Level
Dalet was one of the first vendors to get a product certified by AMWA for creating UK DPP delivery specification compliant files.By Dalet Editorial | 01/26/15
Next week, in a corner of the Bayerischer Rundfunk campus in Munich, Germany, likely without much fanfare, something fairly monumental will take place – the IRT MXF PlugFest.
Now in its ninth year, this event brings together vendors in the media and entertainment industry to facilitate MXF interoperability tests. Following each event, the IRT (Institute für Rundfunktechnik) publishes a report on the levels of overall interoperability, standard compliance, decoder robustness, and the common errors and interoperability issues. All of the previous eight reports make interesting reading (particularly if read in order), but none has been more greatly anticipated than the report due from this ninth PlugFest.
What then, you may ask, makes this year’s event so special that we would dedicate a whole blog post to a relatively small, vendor-only event in Bavaria?
The UK DPP (Digital Production Partnership) has been closely watched by a number of industry organizations and groups, particularly with regards to the file specification it has published, based on AMWA AS-11 for the delivery and interchange of media files. This specification aims to end the headache of media file interoperability at the point of delivery for broadcasters and media facilities across the UK and Ireland.
While the issue of file compatibility is not unique to the UK, unique challenges in the German-speaking media community have dictated a slightly different approach to the creation of a standardized interchange format.
The ARD group, the Association of Public Broadcasting Corporations in the Federal Republic of Germany, is made up of 10 member broadcasters, covering regional, national and international distribution, who have the capability to exchange media at almost any point in any workflow including news, production and archive. In July this year, together with ZDF (in English: the Second German Television), with support from other German-language public and private broadcasters, the ARD published two new MXF-based media file-format “profiles.”
At this point, you would be forgiven for asking, “Do we really need another specification/standard?”
In fact, the two profiles, named HDF01 and HDF02, are not too dissimilar to the AMWA Application Specifications AS-10 and AS-11. What makes the ARD-ZDF MXF-profiles different is that not only do they describe what the output of the MXF encoder should look like, but the tolerances and behavior of MXF decoders. For example, MXF files compliant with the profiles shall not have any ancillary date tracks (commonly used for the carriage of subtitles or transitory audio and aspect ratio metadata), but to ensure interoperability, it is required that decoders are tolerant of ancillary data tracks that may be present.
Specifying not only the encoder, but also decoder behavior will have a massive benefit to interoperability, particularly when deploying and testing systems. Many of the properties specified in the profiles are low-level elements that frequently cause interoperability problems that require lengthy discussions between multiple vendors, users and integrators to find resolution.
Constrained encoding profiles ensure that “problematic” files can quickly be analyzed and “non-compliant” elements identified, but without specifying additional decoder requirements, applying these constraints can introduce as many challenges as they remove with little or no consideration for legacy assets or flexibility to find quick, short-term resolutions to interoperability issues in workflow.
Dalet is proud to have been one of the very first vendors to have a product certified by AMWA for the creation of UK DPP delivery specification compliant files and is equally pleased to be going into the first IRT MXF PlugFest since the publication of the HDF01 and HDF02 ARD-ZDF MXF profiles, as one of the first few to fully support the new profiles.
The event next week will set the baseline for a new era in media file interoperability and, while reading the historic MXF PlugFest reports is interesting, I personally cannot wait to see what I expect to be the biggest change yet, between the report for next week’s ninth and 2015’s 10th event.