Playback automation - TvTechnology

Playback automation

Choosing the right playback automation system for your application can be a scary job, knowing that you and your entire operation will have to live with
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Choosing the right playback automation system for your application can be a scary job, knowing that you and your entire operation will have to live with the decisions you make for a long, long time. It's a sobering experience.

Today, the on-air playback automation system forms the nucleus of every television station. In addition to direct on-air playback, it interfaces with many supporting departments, such as traffic automation, newsroom automation, weather computers and graphics. As with any large-scale project, the key to successful implementation is to divide this large project into smaller, bite-sized projects.

Essential components of any broadcast automation playback system include the server(s), the automation software, prep station(s) or ingest technology, and device control. The digital transition approaches the final phase in February 2009; however, many stations still rely on master control digital islands to route network HD to their transmitter, while bypassing an otherwise all-analog plant.

Broadcasters with these digital islands can pay substantially more to implement an automation system than an all-digital facility might. The required A/D signal conversion equipment, device controllers, monitors, machine controls for tape decks, satellite dish, pan-and-tilt controls and tallies for analog control rooms add significantly to the total project cost.

Let's work through a process to build an automation system for your station. We'll start by asking some basic questions. First, what do you expect this system to accomplish for your station operation? The answers to this question are not technical; rather, they are operational.

Is the goal to reduce headcount? Is it to decrease the number of playout errors? Do you want to handle more channels with current staff? The answers will influence the system's features.

Space and bit rate

Server selection and sizing is based on at least two key aspects. How much content do you need to store, and what bit rate will be used? Both of these issues apply to SD and HD material. Obviously, HD material requires both a higher bit rate and therefore more server space.

Begin by calculating how much content you will need to store on the server at any given time. Determine the number of hours needed per week and then for a month. This represents the nearline storage required to house all active program content that may be needed for online playout. Don't forget to allow for seasonal changes. You'll need more space in December than you will in May.

Then add a fudge factor to that total, usually 1.5 times the calculated amount. The fudge factor will absorb unforeseen program changes, additional program streams and seasonal commercial volume variations.

The RAID drives that combine to form the total memory and function as one large disk should be configured two-thirds active one-third parody. In a RAID 6 configuration, four RAID drives would be active, and two would be parody drives. Memory may be increased later, usually in 400- or 500- hour increments.

DTV standards do not specify the scanning format to be used by broadcasters; it is as much a business decision as it is a technical one. In effect, any scanning format may be used (720p, 1080i, 1080p), provided the total transmitted digital bit rate — a multiplex of video, audio and ancillary data — is equal to 19.38Mb/s. Standard-definition commercial content is usually processed at 10Mb/s. This bit rate will accommodate most content ranging from SD programs and commercials to news clips.

Select an appropriate bit rate and format to be ingested to the servers. This will determine how much memory or storage real estate will be required per minute of SD video. Do the math, and size the main server memory capacity accordingly. The average mid-sized television market may order 10TB (134 hours of SD), or about five days of program content.

High definition has a completely different pedigree. While the minimum HD bit rate is 20Mb/s, some facilities, such as PBS, use 45Mb/s for post production, even though the final program video stream is only 19.38Mb/s. Some networks rely on a variable bit rate, but that is a subject for another time.

Storage

Engineers often overbuy storage. Recently, IBM issued a white paper that addressed the toxic terabyte, which is the inclination to create a vast wasteland of excess server memory or data dumps. Users sometimes find it easier to just keep dumping content into a server than to properly manage the amount of nearline and online storage.

If 10TB were needed today, wouldn't 20TB be twice as good? Maybe not, and here's why: Storage costs continue to drop. Buying 20TB of storage now may cost more than buying 10TB now and another 10TB in 12 or 18 months. Over that time, improvements will be made in the storage platform, and drive costs could drop.

Also, and often not considered, the station will be paying for additional power consumption and cooling requirements for that extra 10TB of storage that's not being used. The one caveat might be if the vendor might go away, or stop supporting a particular type of storage module. If you think that's a possibility, then perhaps you need to reconsider the vendor.

Servers can ingest or output both SD and HD, separately or simultaneously. With HD at 20Mb/s and SD at 10Mb/s, the server capacity requirements are highly dependent on the amount of HD content used. However, the real cost of the HD/SD mix on any program stream actually lies in the external equipment — the conversion, encoding, switching and routing process necessary to achieve a smooth transition between formats.

Required number of ports

The number of input and output channels required is unique to each station, but this is no place to skimp. When choosing the number of I/O ports, be sure to allow for expansion. Include additional ports for services you may not currently be providing. This might include channels for HD direct feeds to cable system head-ends, ingest sources for news clips, satellite program feeds and commercials. Then, after you've totaled all the needed channels, add two more. Trust me, you'll need them.

What about audio? Unless your requirements are unique, six channels for 5.1 surround audio should suffice. However, keep in mind that some audiophiles are pushing for 7.1, so it may be wise to allow for growth.

Choosing software

A critical consideration is ensuring that all of the station equipment under automation control can talk to each other through the automation system. Each device must operate and understand the automation system control commands. Also, proper interfacing with the traffic department software is essential.

Be absolutely certain that the traffic software and the automation software are sufficiently compatible to support the transfer of daily playlists. It's also wise to be sure that your traffic playlists are backed up in master control via a USB thumb drive or other mobile media.

In addition to just routing the program content to air, an automation system must also control bug and graphic insertions for branding and special effects such as breaking news and weather. Simultaneously, the system will control the offline router switching and machine control to perform scheduled recordings. This means proper interfaces will be needed for your satellite dishes, tape machines and ingest server.

Automation systems typically support live playlist insertion as part of their standard offering. Scheduled live local weather updates or newscasts are simply part of the daily playlist from the traffic department. This means the live sources must finish on time because, ready or not, the automation system is going to switch.

This is seldom a good solution. Therefore, your selected automation system should permit manual override, ripple any of the time effects down the playlist and then adjust the following events.

Live events such as breaking news or storm/weather updates must be accommodated. Be sure your automation system can provide easy, clean manual break-ins and even more important, smooth rejoins. Don't expect a master control operator to be able to calculate program and commercial lengths and then manually adjust timings to get back on schedule for the next network join.

An important feature of any playback automation is the ability to provide an accurate as-run log. This log tracks exactly what transpires throughout the day. When problems develop, it can also produce a discrepancy report.

The report will reveal every action taken by both the automation system and an operator. Such information becomes a useful tool when troubleshooting exactly what went wrong. In addition, the report is an impartial and automatic record, eliminating operator claims and counter claims of what happened.

Backup

Some networks and large operations insist on backing up their operation with a second automation system. This budget-busting, mirrored operation may reduce sleepless nights for engineering management, but it's really unnecessary. However, there are some things you should consider when planning for emergencies.

Be sure your system has provisions for running the playlist from a second control point. This could be a media prep or ingest workstation, but at least one non-MCR location. Also, the automation software should reside in more than one location within the system. Access should be protected by appropriate conditional-access passwords to prevent unauthorized changes or activation.

With careful planning, it's simply not necessary to build two complete systems. Such a solution is expensive, requires constant maintenance and checking and is as likely to fail as the primary system. Today's automation systems are highly reliable. A properly configured transition to manual operation capability is a cost-effective option.

Archiving tasks

Some stations decide to install a smaller air playout server and a larger second archival server, where the system will operate in a data push-pull manner from nearline (archive) to online. The archive server could be 8TB or 16TB, depending on your needs and budget. The 8TB system will cost about $35,000, and one twice that size may cost about $50,000.

Before you reject building an archive system, ask your news director if he or she is willing to just throw away all those old tapes in the library. Probably not. Then consider that archiving anything on videotape is risky. Plus, maybe the only person who knows what's in that library retired two years ago.

A long-term archive must be on an offline medium that is reliable, searchable and stores content on a stable medium, perhaps on DVD, optical or holographic disks or data tape. Anything being stored on videotape should be moved to an acceptable archive format while there's still time — and the technology to playback the content.

A unique solution

There is no cookie-cutter template for the ideal automation system. Vendors should walk you through how their products will handle each of your desired tasks. Are their solutions inclusive? Do they occur automatically? Do they fit within your workflow?

Here are some key points to remember:

  • Do not overbuy storage. Storage costs continue to decline, so wait to expand.
  • Buy enough size so you can expand.
  • Be certain the operating system is compatible with your operation. Can you tie a Mac OS to a Windows OS to a Linus OS? Yes, but why risk it?
  • The system should be controllable from more than one location.
  • Stay with reputable manufacturers; you get what you pay for.
  • Ask the vendors for a list of current customers, and then call them. Compare how those stations operate to your workflow. Compare apples to apples. You won't be able to get a good comparison to your needs if you're a commercial station and the vendor suggests you call a noncommercial station.
  • Ask about support after the sale. Does the vendor provide 24/7 phone support? Ask how software upgrades are handled. Think about your experience at installing service packs on your own PC. Now, imagine doing something similar on your station's automation system. Need help?

Purchasing a station playback automation system isn't for the faint of heart. However, break down the desired tasks into a list. Compare your needs with several vendors' products. And ask lots of questions.

Leo Demers is a broadcast consultant.