Effective DAM system
The adoption of digital asset management (DAM) by broadcasters has had a long gestation period, with many potential users failing to see a sound case for the investment. The problem is that original DAM products often came from a background of document management or image libraries and did not match broadcasters' needs.
Much has changed in the last five years. The biggest change has been the move from videotape-based to file-based post production and playout. By leveraging commodity IT infrastructure, more cost savings can be had than by the old linear tape methodology.
Videotape is a physical asset and can be managed by using traditional library methods, with numbered shelves and bar codes to track check in and check out. When content is handled as data, the assets become ephemeral or virtual. The management of these files or digital assets requires a DAM system that is designed specifically for broadcast requirements.
DAM and broadcast meet
Many of the early products used for broadcast were enterprise-scale, with associated costs. Broadcasters already attempting to absorb the cost of the move to HD and multichannel operation across multiple delivery formats could not see the ROI on the multimillion dollar systems. However, the multiple channel and format business can be made more efficient by using DAM, so many broadcasters are revisiting the financial case.
There are some issues with using enterprise DAM systems. They are deployed to handle the service side of a business, such as brand assets, documents and image libraries. In the TV industry, DAM has to handle the final product. That product comprises large files, only equaled in sectors like oil and gas exploration.
Conventional enterprise DAM is not designed to index and manage the storage of these large files without third-party add-ons. A DAM system alone may meet the needs of a program or news archive, but most broadcasting applications need allied workflow management.
Early adopters of DAM had large videotape repositories that they wanted to mine as a means to sell library assets or to manage a news archive. With the addition of a video indexing system, an enterprise DAM system could be adapted to fit the purpose. The advent of file-based workflows and multichannel delivery has led to a demand for more cost-effective and videocentric DAM systems.
Creating more programming for less money is impossible using the traditional processes of videotape. The scale of manual handling, real-time copying and constant QC checks required by tape has led broadcasters to adopt the methodology of IT systems in the search for cost savings.
Recently it has become apparent that workflow management and optimization are just as important as DAM in the migration to more efficient broadcast processes. Just as the office has moved on from document management and e-mail to adopt collaborative products such as Microsoft SharePoint, broadcasters have realized that efficient use of human resources is just as important as the program assets in creating a streamlined business.
What does a broadcaster want from DAM?
Some companies may want a system to manage an archive for internal use or the sale of stock footage. Some may need a system to manage content from acquisition to air. Others may need to repurpose for new media outlets such as IPTV or Web streaming. All these applications share a common trait but will need different application modules to support additional services.
Not all products include the necessary features. To provide the full functionality, they need integration with third-party applications. The core of DAM is comprised of several modules to ingest, catalog, search, store and publish content. (See Figure 1 .)
As cameras migrate from videotape as the primary storage media, acquisition from solid-state memory presents an immediate application for DAM. The media has become a temporary cache, to be copied to a file repository so that the memory can be reused. There is no longer a handy box to keep the dope sheet with the tape. There is no label to scribble notes on.
The adoption of digital media, however, creates new opportunities. For example, a production assistant could use a PDA to add notes as metadata to a linked file. Registering assets may only be necessary to encode a browse copy with a reference to the original source media, much as offline editing is used with camera negative.
The DAM catalog comprises folders arranged in a schema to suit the needs of the broadcaster, along with a means of indexing the catalog to aid search and retrieval. Video and audio content does not readily provide the information for text searching, so the system must rely on the input of additional metadata by production staff members. This can be difficult, because it requires weaning personnel off the sticky note toward more formal keyboard entry.
For most users, the search portal is the main interface with DAM. This is used to find material, either via catalog or using a search. Results are typically displayed as a lightbox, with the facility to play a browse (low-resolution) instance of the asset.
The search portal can be used with NLEs, ideally to drag and drop clips from across the GUI into the timeline. Finished edits can be registered to the DAM from the same interface.
Unlike document management, the design of video storage systems is complex. At a reasonable cost, the system should be able to serve large files at high data rates. Systems over 50TB may well need special high-performance file systems, as office systems like NTFS and CIFS may not meet the requirements. A typical system may have four hierarchical layers: SCSI or Fibre Channel drives for editing full-resolution video, SATA or Serial Attached SCSI (SAS) for lower cost nearline spinning disks, an automated tape library for Super Advanced Intelligent Tape (SAIT) or LTO data tapes, and a low-cost deep archive of tapes on shelves.
These storage layers all need management that ensures what is needed is served in a timely manner. Conventional hierarchical storage management (HSM) is rarely suited to applications like playout, where large files may need to be recalled from tape rapidly. The HSM needs to be aware of the playlist to prioritize restoration to disk, which is a key function for a product developed especially for the broadcast industry, rather than for enterprise IT.
Early DAM had simple publishing requirements, usually involving running out a file to Digital Betacam. Multiple delivery channels have made publishing more complex. A file may be needed as 1080i or 720p in MPEG-4 AVC, SD in MPEG-2 or 320 × 240 in a mobile codec. There have always been different frame rate requirements for 25fps and 30fps, with 24fps a new alternative.
It has become mandatory for DAM to include either an integral or third-party transcoding engine through Web services. Such engines also need control from the workflow to schedule jobs.
Aside for the core functions, DAM will also include security and interfaces to messaging systems. Security provides a layer to control access to content, to authenticate users, and to group and assign roles to those users. A given role may be allowed a subset of functionality and limits to write access. Access can also be managed on a project basis.
The essential extra features include NLE integration, links to program and artists' rights management, resource scheduling (human and hardware), transcoding and workflow automation. If DAM is used alongside playout, then links will be required to program, planning, traffic, sales and playout automation.
Once implemented, DAM is a great enabler. Review and approval requires little more than a Web portal. Program sales can be enhanced by exposing the archive to potential customers, and repurposing channels, such as for IPTV, becomes far more cost-effective.
It's not just audio and video
DAM has always stored metadata to aid searching and the production processes. Television production can carry large amounts of textual data from production notes through to scripts. As a product enters the post phase, it acquires graphics, such as Photoshop, animation and 3-D files. The asset management system must be able to handle all the common formats used in broadcast, which is not a short list.
Early systems encoded content at ingest as proxy at a low bite rate for browsing and an offline resolution for cuts-only editing. The content was simultaneously encoded at broadcast resolution as the primary digital asset.
As broadcasters optimize their systems, they want I-frame coding to support editing and long-GOP for long-term storage to make efficient use of their archives. Transcoding can also be used in content publishing applications as broadcasters deliver to a wider variety of devices like iPods and mobile TV receivers. This has led to a demand for transcoding engines as well as encoders. This part of the system design should be considered carefully to avoid the artifacts associated with concatenation when performing several transcodes.
Few productions are entirely file-based. Film, videotapes, audiotapes and optical disks may all be used in the production process. These physical assets need to be integrated into a DAM system so they can be searched and retrieved in the same way as online digital assets. Traditional library software with bar codes provides the functionality, so a link via Web service should provide easy integration. Proxy viewing, however, assumes that the physical content has previously been digitized and indexed.
It's important to note that the distinction between media asset management (MAM) and DAM is blurred. Many products offer considerable overlap or even total support of physical and digital assets.
Implementation and change management
The most important question to ask when selecting asset management is, “Will it be the right system for my business?” It is not unheard of for businesses to be on their third vendor after products fail to live up to promises. Such issues can be avoided by running pilots, as the best way to become familiar with a system is to use it in earnest.
DAM touches all parts of a business. Therefore, selecting the right product is essential to the efficient operation of the business. A wrong decision will affect the bottom line and alienate staff.
There are four principle costs when deploying DAM:
- the product cost;
- the fees for the professional services to implement the DAM;
- the ongoing maintenance costs; and
- the staff time needed to implement the inevitable workflow changes when switching to file-based production.
The fourth cost is most difficult to measure. It is essential to employ proper change management to avoid unexpected costs. Change management should ensure the proper acceptance of DAM with attendant operational efficiencies that should lead to cost savings.
Digital asset management has progressed in the last few years to become a fully featured infrastructure for file-based production and broadcasting. Early products were little more than a fancy file manager. The current round of products has evolved to meet the real needs of broadcasters by adding to the basic toolbox. The integration of workflow management and control of video storage, alongside the release of more cost-effective products, means that asset management has become essential for broadcasters who want to lower costs, yet deliver more.
As more broadcasters use DAM, product costs will drop. This can only accelerate its acceptance.
The second edition of David Austerberry's book “Digital Asset Management”can be ordered directly from the publisher atwww.focalpress.com. The book is available from several booksellers.
Get the TV Tech Newsletter
The professional video industry's #1 source for news, trends and product and tech information. Sign up below.