A small, centralised approach to automation can offer broadcasters an increased degree of flexibility and ease the path for future expansion in a changeable market, writes Rob Leishman, as broadcast engineers look to take on a future with moving targets.
With the switchover to digital transmission the new range of television and set top boxes (STB) rely on a lot of specialised computing and software technology, the only thing different from a PC architecture is the keyboard and mouse are replaced by a remote control. The future generation of viewers will treat the television screen as a display for multiple information sources as they do at present with their PC. Broadcasters need to ensure that the television channel being displayed as an application holds the viewers attention. They will have to use the large volumes of multi-format content they will handle in a sophisticated way.
To ensure that the viewer’s attention is captured and maintained conventional broadcast material will require a level of interaction or perhaps be offered in HD, providing additional value to the advertisers and sponsors. By failing to evolve, broadcasters will lose out to competitors that address these demands and offer a more compelling experience for viewers and advertisers alike.
For some small, start-ups or emerging broadcasters, accommodating these likely demands may seem like a daunting prospect. They need to match plans for growth with scalable, future-proof technology for the successful development of their station. However, the good news is – from an automation point of view – that bigger is not always a better way to manage these multiple technology challenges.
The key point when selecting any automation system is to choose one where the underlying design comes from a top-down approach. This means it is possible to configure and easily change workflow and there is the ability to logically link any type of device at a conceptual level. In other words, the system incorporates a range of templates to allow the addition of any new device like a server, mixer or router for example, at anytime. Tight real-time integration of a particular brand of device is incorporated in software modules that operate in real time, close to the external communication link.
A base design that encompasses top-down development techniques will therefore, work with any other device regardless of whether that is a media management, storage or archiving system for example.
Each type of device is represented by a standard framework or ‘Logical Device Template’ with its own unique data structure allowing the characteristics of the device to be stored, ensuring the top-down arrangement is essentially future-proof. Logical templates are assigned to each physical device and any upgrade to the template is automatically reflected down to the applications it interfaces with, making any necessary changes to peripheral equipment a simple process.
The logical device templates are configured into the required workflow and maintain information flow with a heavily optimised database providing real time information and control.
The Protocol Device for communicating with each specific brand of device is maintained separately and operates at or close to the external physical connection. Integration is simplified as no control logic is included at this level and as a result, the system can manage and control any current system or one that is yet to be created.
This set up also ensures that commands such as; ‘play a particular movie’ for example, are received at the device level, ready to be triggered on the frame boundary. To operate frame accurately in accordance with the broadcast schedule, the command either needs to include time stamping or, if there is latency, be transmitted to arrive at the device activating the required action a predefined number of frames beforehand. To achieve overall frame accurate broadcasts, the communication to all of the devices needs to be synchronised and to utilise a centralised architecture with a real time operating system. This allows each interface to operate in accordance with the high-level control algorithms rather than trying to get devices to work together by changing the timing of control signals to one device to work specifically with another device.
A centralised architecture provides single control reference to ensure that all facets of a multi-channel environment can be synchronised. The control reference must not only use a recognised time source to synchronise events but also ensures that any offset required to cater for the characteristics of each individual device attached is still relative to the control reference. The combination of high bandwidth and guaranteed low latency ensures that frame accuracy is provided consistently and independent of any changes in the characteristics of the broadcast environment itself.
In the past, large computer systems were required utilising a real time operating system (RTOS) such as OS9 to provide sufficient processing power and memory to accommodate the software needed to control a multi-channel system. Nowadays, new and faster CPU processor boards are available. These can be linked with additional processor boards acting as communication servers using an internal bus, which provides high bandwidth and guaranteed low latency for inter-processor communication.
Configured like this in a centralised architecture, the computer system no longer needs to be large.
A typical small centralised architecture would find the integrated broadcast automation software running on a master control processor while the communication servers communicate over LAN, Serial and GPI signals controlling the peripheral equipment over physical connections
The centralisation of all system resources such as recording, playout and duplication along with the immediate availability of associated meta-data and state information allows a high level of automation to be achieved in a multi-channel broadcast environment.
In the future, the viewer will have the tools to set the agenda and request media from the broadcaster acting as a giant media server. The centralised automation system is well positioned to service the existing business model providing scheduled playout and the future business model by becoming a gateway to the media server.
Increasingly compact automation systems are now available but with differing levels of functionality. In a centralised approach the software is easy to configure and support providing a flexible yet highly scalable solution to the demands of current and future automation, proving that bigger is not always better when it comes to broadcast automation.
Rob Leishman is marketing manager at Abit.
Compact is key
Playout specialist Abit offers a cost effective automation platform capable of supporting three transmission channels.
“Customers wanted an option to take advantage of the wide range of functionality and expertise Abit has developed, but without the need to control a large number of devices in a multi-channel architecture,” explains Richard Thomas, software development director, Abit. “Our solution gives them access to the full power of the application software in a much smaller non-redundant platform.
“The main benefit of this approach is that Abit will continue to develop and maintain a single source of software configured to run on its existing systems, which allows customers for the new compact system to take advantage of future product enhancements.”
The IT standards approach
The iTX software based transmission and production tool by Omnibus includes automation with a host of plug-ins available to expand the feature set. These include the addition of graphics, logos, vision effects, voiceover, live events and audio effects, claims the developer.
An integrated character generator allows the operator to create CGs or load and modify templated material. The system also supports open and closed subtitles and multiple audio tracks, according to Omnibus.
In addition to these features a drag and drop function simplifies the process transmission enabling a single operator to work on multiple channels if desired.
The iTX system uses only standard IT hardware.
OASYS (formerly On Air Systems)
Neat and tidy
The full OASYS software workflow is based on standard PCs, meaning it can be commissioned in days and requires minimal training and maintenance.
According to the manufacturer, the Player module offers a number of features as standard that mark it out among rival automated software-based playout systems. These include “on the fly” schedule creation and time-unlimited advance scheduling, trim, edit and transition effects, and a number of configurable error and alert options.
As expected Player is compatible with third-party systems including routers, MXF, storage and editing systems.