Installed at Viasat is both Harris’ D-series automation playout and its Landmark and Broadcast-Master systems for air-time sales and program scheduling.
Fear of the new
Many broadcasters in Europe have deployed digital asset management (DAM) systems for news production, transmission systems and program archives. The early DAM users were large networks or state broadcasters. The initial product offerings were expensive, enterprise-scale systems. Now there is greater choice, and prices are becoming more affordable. One of the key factors in cost reductions is the development and adoption of standards for metadata and content wrappers. Interoperability saves costs, and there is less need for customization with the attendant professional service fees.
Broadcasters have had a comfortable relationship with videotape since the first Ampex came into use. Like film, it is a physical asset. You can put in a box and stash it away on a library shelf. If you want to track it, you can add a bar code. If you need metadata, you can put a slip of paper in the box. If you want sophistication, you can link the bar code to a database.
As broadcasting moves from specialized equipment to using commodity hardware from the computer industry, we are seeing a migration from film and tape, and from live video, towards a file-based environment. Some areas of the production workflow have processed video as files for more than five years. Nonlinear editing and transmission playout systems both use disk-based storage. They have generally been accepted as offering lower prices and better performance than tape-based systems.
Figure 1. When ingested, assets are indexed and cataloged. Then the files are held on a storage network, where they can be browsed. The final step is publishing, where assets can be turned into revenue by distribution over many channels. Click here to see an enlarged diagram.
These two applications have been treated as islands. The input to the editing process is videotape, and the editing program is delivered to the playout center as videotape. The step from this, to a tapeless workflow, raises many issues outside the simple problems of moving media around.
With new camcorders offering recording to optical disks and solid-state storage, there are further pressures to find new ways to make programs that can realize cost-savings without sacrificing the flexibility that the creative programme makers demand.
There is a fear in many circles of losing the physical asset. Will a file get lost? What happens if a disk crashes? There is a good feeling about seeing a finished program sitting in the tape library.
If we step away from the world of television, we are happy to use files in the rest of our lives. Who goes shopping with a pouch full of coins? We use a charge card. Our money is trusted to the banks' computers. Look at music; young people are abandoning physical media. The vinyl disk and the CD have been replaced by the file download.
Figure 2. Digital processing islands in post-production, newsroom and master control. Click here to see an enlarged diagram.
Once you overcome the fear of moving from real to virtual content assets, there are other impediments. How do you manage the files? How do find a clip? How is it handled by the different production applications: the editing workstations, graphics and audio? The simple answer is to use DAM. But DAM raises other issues. One is return on investment (ROI); the other is interoperability and standards.
Early adopters of DAM have seen a direct benefit. With broadcast news, DAM gives desktop access to the news archive. For the broadcast publisher that has to feed multiple channels in multiple languages, DAM enables repurposing at affordable prices.
DAM can be a high-ticket item. This does not stem necessarily from the product itself, but from the professional services needed to integrate the DAM with the rest of the network or group of stations.
Videotape has been an incremental investment. There is the occasional purchase of a deck to replace a worn out unit or to cater for a new tape format.
Enterprise-wide DAM is a big capital investment. Because DAM is intimately linked to all parts of the business, the installation of the system will carry some risk. A successful deployment of DAM will demand buy-in from all the users and, most likely, a step change in working practices.
Interoperability
The advantage of using tape is that interoperability between departments is simple. As long as the sender and receiving department have the same format of tape deck, then the program can be interchanged.
Figure 3. A repurposing production cycle is replacing the traditional linear workflow of television production. Click here to see an enlarged diagram.
Without the adoption of standards, file interchange can be difficult. Acquisition may use DV compression. Editing may be uncompressed. Transmission may use MPEG-2. There are the issues of line/frame rates and interlace/progressive scanning, I-frame or long-GOP. It may be necessary to render a file as uncompressed real-time video and then re-encode it in a different format. This intermediate real-time video rather defeats the object of file-based workflows.
There are other systems that must interface with the asset management and share data. These include airtime sales, traffic, billing, planning and rights management. In principle, these systems can exchange metadata, but what metadata?
Many state broadcasters have invested in DAM to protect an archive of historic material. DAM offers much to the archivist. First, it is a good opportunity to digitize decaying media. This could be nitrate film, early color film with fading dyes, or early videotape formats such as quadruplex. Once an asset is digitized, it can, in theory, be copied to fresh media as the substrate nears the end of its life. It is perfectly possible to automate such file migration.
Archive
Once an archive has been rescued from slow decay, indexed and cataloged, it can be made available to the general public. Schools benefit from access to material shot at the time of the pupils' grandparents. The recent history of their locale can be viewed online. This ready availability of a historic film archive can be useful to the program researcher. It opens the door to lower cost documentary production by making material easy to browse, with broadcast-quality copies available with the ease of an Internet shopping portal.
Many archives that have adopted DAM have decided to save storage costs by keeping browse proxies online and the broadcast media offline in conventional tape libraries, either as data tape, or the original videotape. This compromise makes sense. For the purposes of education, streaming lower resolution files gives adequate access to the archive. For the program researcher, the material they need to cut into their program will represent a small fraction of the material that they browse. Although they will still have to order up dubs, the research process is much faster than conventional copying of masters to VHS for viewing.
Transmission playout is one area where DAM really scores. Material is often delivered as files, especially short items such as commercial spots and interstitials. The storage requirements are not large, as material is usually played a limited number of times, after which it can be purged from the servers.
Playout
The concept is based on the old tape robots that were the primary vehicle for commercial playout for about 20 years. The robots ran playlists from the scheduling system. Some could create automatic back-up reels to improve the reliability of the transmission operation. Using a DAM system, the system can be made much smarter. The browse copies mean that the staff in traffic and scheduling can see the video clips they are managing; they are no longer restricted to a list of program titles and house numbers for commercials. The media management that comes with DAM can move files around to suit the requirement of multichannel operations. One instance of a clip is sufficient for any number of channels; with tape, several copies could be necessary to allow the same commercial to be aired to many channels. This extends to the wide-area network found with regional television stations. DAM can control the delivery of clips to remote servers, a major logistic operation with tape or live video.
One of the issues that has held up the adoption of DAM by broadcasters was the lack of standards. Now that MXF is being introduced as a file wrapper, it is becoming much easier to move files around broadcast systems. New camcorder designs can deliver MXF content direct to the storage repository.
Standards
The Pro-MPEG Forum (with MXF) and the AAF Association are helping to standardize the handling of file-based audio-visual files and are encouraging their use.
DAM now has reached the maturity where it has much to offer broadcasters. It would be difficult to move to a file-based workflow without DAM in one of its guises. So the decision is not whether to purchase DAM, but whether to use enterprise-scale or to have an ad hoc roll-out with workgroup systems — the typical example being the editing department using shared storage as an island.
We will see far more DAM in the immediate future, once the advantages of streamlined and efficient workflows are understood.
David Austerberry is the editor of Broadcast Engineering's world edition, as well as a technical writer and consultant on video technologies. He is author of “Digital Asset Management: How to Realize the Value of Video and Image Libraries,” published by Focal Press.
