A member of the public touring a TV network could be forgiven thinking that its main product was tape cassettes. Each office has piles of tapes, and people are pushing carts full of tapes down long corridors. The real business of television, making pictures, is hidden away in small islands: online edit suites, master control and the newsroom.
IT has transformed the conventional office. The dictating machine and the typing pool have been replaced with the word processor. The internal memorandum delivered by an internal postal system has been replaced by e-mail. This revolution has been somewhat ironically called the paperless office. Television's move to IT has been similarly dubbed tapeless production.
These simple labels conceal the real benefits of the adoption of IT. The advantages lie in more efficient use of production resources rather than the elimination of paper or videotape.
Table 1. Typical compression in the program chain. Click here to see an enlarged diagram.
IT-based television uses commodity IT hardware and software for operations that traditionally use custom video hardware. This delivers great cost-savings, but also it allows the advantages of IT systems to be leveraged. These include networks, shared storage and databases. Aside from infrastructure, IT-based systems also promise improved integration between the creative processes and the many back-office applications, from planning and rights through to sales and accounts. Potentially, this offers improved business intelligence not only for production, but also for subscriber management systems and audience interaction to provide demographic information and improve advertising revenues.
Why IT-based television?
Traditional television broadcasters are beginning to see competition from other sectors such as telecommunications. Questions hang over interstitial advertising as the primary revenue for television. As audiences adopt the PVR rather than live transmissions for viewing, the ability to skip commercials is threatening old business models. This changing media landscape will force broadcasters to look for more efficient ways to produce and distribute programs.
- Lower cost processing platforms.
- Collaborative storage environment.
- IP-networks for distribution and delivery.
It sounds easy, but the use of IT equipment to handle video throughout the production process has only recently become viable. To be competitive with conventional equipment, high-speed processing and low-cost disk storage was needed.
The latest dual-processor workstations are very good for SD video, but computationally intensive processes such as effects and encoding still benefit from hardware acceleration, especially for HD.
Advances in IT hardware
High-performance RAID storage now can be had for less than E2 per GB. That is about one minute of uncompressed SD video. Tens of terabytes of storage are now commonplace in quite modest-size TV companies. The other requirement was a high-speed network, now largely satisfied with gigabit Ethernet (GbE).
Television production has been a linear process. Content was passed from one department to the next in the chain. Parallel operations were limited to graphics and sound design. The audio tracks were laid off and then laid back to the video after editing and mixing. Nonlinear editing introduced the possibility of collaborative working with the same material, something not possible with tape. The enabler was a shared storage system that would allow several editors to work concurrently on the same set of clips.
The concept of shared storage is now commonplace within the islands of editing, news and multichannel playout, but it has not been generally available to the rest of the production operation.
Building a high-performance yet affordable video storage network still presents several challenges. Editing networks typically support as many as 50 seats. A TV network may need to scale to hundreds of seats. With this demand comes several problems. Special file systems are required to meet the performance demands; connections have to handle high bandwidths.
Until recently, video storage networks have used high-performance connections such as Fibre Channel. Conventional 10/100 Base-T Ethernet networks did not have the capacity for video signals. That is changing with switched GbE, but the move from SD to HD has raised the bar.
Video compression has always eased the demands on storage and networks. Just as videotape formats use compression to achieve sensible tape consumption, broadcast processes can use appropriate compression.
HD production increases demands four-fold. The larger files and higher data rates of HD have negated the advances in storage system performance that stem from improved disk and network technology. But for most broadcast applications, all that is required is a viewing copy or proxy. It is only the operations of editing and finishing that require the full resolution files.
Shared storage is only required where users need to collaborate. Elsewhere a storage network will meet demands. To transfer media across the network, standards are needed to ensure interoperability. The most promising formats for the broadcaster are AAF and MXF.
MXF files do not solve all the issues of file interchange across IT networks. Within the wrappers can be several operational patterns (OP) for different codecs such as MPEG, DV and JPEG 2000. To fully support a free movement of files, transcoding engines are required. System design should ensure that concatenation of codecs does not create unacceptable artifacts in the main broadcast media workflow.
IT-based production raises the question: What format to use for the archive? Tape-based production can store original camera tapes, plus the finished program master. In a tapeless production chain, what should be archived and in what format? Should it be compressed or uncompressed, long-GOP or I-frame coded? The answer will lie in the value of the material balanced against the cost of storage.
Behind the production processes that create the finished program lie many management services such as resource scheduling, work orders and planning. Integrating the back-office has often proved costly. Expensive professional services have been required to create highly custom interfaces between different applications, whether rights management, planning or finance. The upgrade of one application often requires further work to restore the operation of the data interface. The initial cost, and the difficulties of support, has deterred broadcasters from integrating management applications.
Integrating the back-office
The advantages of back-office integration can be seen in many other industries, so how can broadcasters find a cost-effective way forward? One technology that has been vaunted as the answer is the service-oriented architecture (SOA) using Web services.
This is starting to be used in areas such as playout for interfaces between automation and the back-office. Using a standardized architecture (such as SOA), the development costs of interfaces can be dramatically reduced. The developers can concentrate on what data is to be interchanged, rather than how.
Web services are not the complete answer, but they can simplify the development of loosely coupled interfaces between applications.
Traditional production uses physical perimeter security to prevent theft of media. In an IT-based content production system, not only is the content archive open to attack by cyber thieves, but also confidential business information is exposed to the network. Web services represent a special problem; carried by HTTP, they can traverse firewalls with ease.
There are many established methods for building secure networks, but security is an expensive overhead and has to be factored into the move to IT-based production.
IT-based broadcasting systems promise to improve efficiencies by easing collaboration and improving the flow of management information. The challenges in its implementation are both human and technical. The global nature of entertainment, along with the diverse channels available for delivery, demand a shift from the old craft approach of program production to the all-encompassing content factory serving television, the Web and mobile devices.
IT-based production has many facets, from the adoption of file-based workflows through to a fully integrated back-office. As IT products become lower cost and higher performance, plus simpler to implement as a system, the reasons to adopt an IT-based production process will become compelling.