Understanding the role of Digital Production Partnership application specifications
DPP is an initiative formed by the UK’s public service broadcasters to help producers and broadcasters maximise the benefits of digital production. The partnership is funded by BBC, ITV and Channel 4, with representation from Channel 5, Sky, S4C and the independent sector on its working groups.
Bruce Devlin, Chief Technology Officer at AmberFin, believes there is still a big challenge in communicating the benefits of file-based production to broadcasters and facilities in ways where they grasp the tremendous opportunities on offer. However a new standard is helping UK organisations across the media landscape benefit from better integration across file-based workflows.
Without doubt, file-based production represents the future of the electronic media industry.
In the UK today around 70 percent of internal transactions within broadcasters and facilities are file-based. But a much lower figure – 10-15 percent – of inter-company media transactions are file-based. Even at the BBC, which is regarded by many as a pioneer in file-based production workflows, less than 24 percent of media transactions with other companies are file-based. The remainder utilise digital tape.
The challenge facing the broadcast industry in adopting file-based production centres on interchange format standards, or rather the ability to adopt one standard. The original purpose of the group that created the MXF (Media Exchange Format) specification was to make a file format for the media industry that addressed its needs in a way that would provide a work-horse for years to come without being the intellectual property of a single vendor.
Over a number of years, the number decreased from hundreds contributing requirements and great ideas to the pool in the early days, down to a mere 10-20 dedicated vendors at the end of the process, refining and developing the standard until it reached its goals.
At the end of 2004, SMPTE published the MXF standard, but no-one spotted that the end users had refocused their attention at the time of publication and the first batch of product was launched by the vendor community using the MXF toolbox in a way that favoured that particular vendor.
No-one is to blame for this – it is a natural consequence of trying to do something difficult in an open forum. Over the next few years, the MXF standard started to lose some of its appeal as interoperability problems prevented complex systems from “just working”.
Individuals within the Advanced Media Workflow Association (AMWA) pointed out that MXF would be better if the business problem solved with the MXF toolbox was more clearly identified. These people worked with forward thinking members of the end user community to create a range of application specifications. The application might be for direct-server playout, or versioning or interchange of mezzanines or exchange of advert metadata. These were (and still are) business problems with a technical solution called MXF. Not unsurprisingly, these problems were the same ones first put forward a decade ago when MXF was being designed.
The Digital Production Partnership (DPP) is perhaps the first of these Application Specifications to receive national scale adoption. It certainly won’t be the last. DPP provides a framework that enables the UK industry to come together and share best practice in digital production and help producers and broadcasters maximise the potential of the digital revolution. Also, it leads the standardisation of technical and metadata requirements within the UK, helping to ensure digital video content can be easily and cost-effectively distributed to audiences via multiple platforms.
An interchange format for the real world
In a world of extremely diverse media utilisation, it is impossible to create a “one shoe fits all” media format. The business requirements for archiving the production master of a new movie are different from the requirements for exchanging a metadata rich proxy across a business network. The best we can do is to have a hierarchy of standards that reduce the number of variants in an application. MXF is the toolbox standard. OP1a is the complexity constraint of the MXF toolbox. AS11 is the application constraint of the OP1a pattern. DPP is the shim (smallest specification) that defines how that application will be used in a given environment i.e. the UK Digital Production Partnership (DPP).
DPP is all about business. It provides solid foundations for future business growth and, importantly, it provides a level playing field for all the companies working within that sector. In a way, DPP provides a sheltered environment or ecosystem in which companies can interact with each other. The other option can be likened to the lawless Wild West where there is no protection and individual companies can make ill-judged decisions that cost them dearly.
Life with or without a DPP ecosystem
Often different departments within the same major broadcaster will adopt slightly different file standards and metadata making interoperability a big issue to them. As a result, today only about 70 percent of transactions within companies are file-based – the remainder employ tape. However, this is much higher than where external agencies are involved; here, only 10 – 15 percent of transactions are file-based. The problem is the lack of a common interchange format to enable these transactions. DPP is the first open public interchange format that is specifically designed to address this issue. DPP is intended to transform today’s 20 percent trickle into an 80 percent flood in the shortest time.
In a standardised DPP world, there would be a limited amount of pain and cost felt by everybody, but this would be shared equally amongst the organisations involved and it would be a limited cost, which is incurred only once. After this point, our industry has a fantastic common interchange format to help encourage partnerships and build businesses.
In the Wild West: In an unstandardised world, where different facilities have decided to use different tools and variants of MXF or other formats, the major cost becomes the lack of third-party interoperability. Each time content is exchanged between different facilities, a transcode or rewrap in that format is required. This means that all vendors in all the facilities will ultimately support all the file formats and metadata. The engineering required to implement and test takes time and costs money on an on-going basis.
In a world that has adopted DPP, media and metadata interoperability is not an issue since the format is built on a strong, detailed common interchange specification. In this homogeneous scenario the resources that would have been used in the interoperability engineering process can be used in more creative and productive ways, such as programme making.
In the Wild West: Programme making is a process where most broadcasters utilise external resources. In an unstandardised world, whenever a broadcaster or production facility receives a new file from an external facility, such as a post house, the question must be asked whether this file meets the requirements of their in-house standard. That evaluation process can lead to extra QC costs in addition to possible transcoding, conformance and metadata re-keying costs that need to be taken into account.
Easing the workflow
In a modern workflow the typical number of file encoding stages between camera and screen is around 10 which include transcodes, import / export in editors, lay back to tape stages, mezzanine encodings, distribution encodings, contribution encodings as well as the “last mile” Tx encodings.
If you have a single interchange format within your workflow then the number of transcode operations can be dramatically reduced – the end product will retain all its quality. The utilisation of DPP as a common interchange format simplifies the workflow and assures that quality levels are maintained throughout. Furthermore, a homogeneous codec environment enables effective QC irrespective of the number of process steps.
In the Wild West: Even within the largest broadcasters, not all production processes are performed in-house. Files will be sent to another department or to an external facility. If these third parties are not using the same interchange format in their operations then format conversion is required. In this scenario, quality degradation is inevitable. So, as previously explained, not only is the re-engineering process adding to time and cost but the end quality of your product quality is also put at jeopardy.
The vendor community is aware of this issue and recognises that DPP offers the solution in the UK. At a recent DPP Vendor Day event, there were 13 different vendors present. They had a shared goal – to make all their products to work together on the DPP platform. It may seem strange that transcode vendors, who in theory should profit from the Wild West, support the DPP initiative. This is because the underlying media ecosystem is not benefitting from the multiple formats that the Wild West has created. Multiple formats are fine when they produce a business benefit. When they produce a business drag then something needs to change.