As countries in Europe and Asia plan new HD services, experience can be gained from experience in the United States. There, the availability of HD programming has continually increased since the first national HD broadcasts in the fall of 1998. Beginning with WRAL-TV in 2000, growing numbers of local broadcasters are producing nightly HD news programs. Nationally, Voom offers a dedicated channel, HDNews, 24/7, and CNN has also gone HD. NBC Nightly News began its national HD broadcast in March 2007.
However, production of news programming and the upgrading of newsrooms to HD capabilities have been somewhat late arrivals to the transition to DTV. Recent industry counts from the United States report less than 10 percent of the more than 1500 terrestrial broadcasters are producing their news in HD. A similar pattern is emerging in Europe with initial HD services being sports and movie channels.
In order to remain competitive, broadcasters that have not done so are finding that they have no choice but to produce their daily news programs in HD. This is especially true for local broadcasters because news operations make considerable contributions to a broadcaster's bottom line. If another station in the DMA has gone HD, there is no choice but to follow suit.
Once a commitment has been made, two migration paths to an HD newsroom are possible. The first is an upgrade of an existing facility; the other is a green-field design and installation. Each has its pros and cons. The choice is dependent on how much (if any) of the existing infrastructure is HD-ready.
Upgrades require staying on the air and necessitate scheduling equipment installation and commissioning around production and broadcast schedules. Because newsrooms never sleep, this is not an easy problem to solve. However, if the facility has converted to digital and installed HD-capable distribution equipment, ingest and playout servers, some of the existing infrastructure can be used, resulting in less of a financial outlay.
On the other hand, a green-field design offers the advantage of being free from the constraints of daily production, and equipment can be installed and commissioned on an uninterrupted, realistic project timeline. However, new equipment must be procured and, therefore, the undertaking will cost more than an upgrade of an existing facility.
WETA-TV, the Public Broadcast Station (PBS) located just outside Washington, D.C., has just completed an HD upgrade. WETA was one of the first stations in the United States to broadcast in HD in 1999 and, in 2006, was the first to broadcast simultaneous HD and three SD channels on a 24/7 basis.
The upgrade, a significant milestone for PBS, enables the HD production of “The NewsHour with Jim Lehrer” and serves as a representative example of what equipment is necessary regardless of which upgrade path is taken.
The project included a new HD video control room; a new digital audio control room with 5.1 surround sound; six new HD studio cameras; three upgraded HD edit suites; an expanded video storage system; four HD field camera systems; two HD studio decks; video servers, storage and archive equipment; expanded HD routers; a rear projection multi-image display wall; and QC/QA workstations.
This is a long equipment list and represents a considerable financial investment. There is only one opportunity to get it right. An HD upgrade is a tricky undertaking. Much of the equipment is evolving; new features are offered frequently by manufacturers.
A serious challenge in any upgrade may be getting all the diverse equipment to work properly and communicate as a system. Let's face it: An in-house engineering staff, particularly at a local station, has probably never designed from scratch or converted an HD infrastructure. Development of functional system block diagrams by in-house staff, who are intimately familiar with the newsroom workflow, is about as far as an in-house engineering department may feel comfortable to venture.
Beyond this point lies the great unknown; the devil is most certainly in the details of an HD infrastructure. This is when the use of a knowledgeable system design and integration company will prove invaluable. Unforeseen problems can be avoided, or resolved before they ever appear. In a complex undertaking, there is no substitute for experience.
Consider the source
News operations face a particularly difficult aesthetic challenge compared to dramatic programming and studio programming. Excruciatingly true for HD is the unavoidable fact that program quality is dependent on the source. Set design, lighting and make-up must stand up to the viewer scrutiny allowed by HD resolution. Fortunately, most stations are meeting the challenge, and talent actually looks better than ever before when make-up is properly applied for HD. HD-friendly sets are routinely designed by theatrical design and lighting integrators.
HD ENG contribution feeds over Broadcast Auxiliary Services or via commercial carriers are emerging technologies. Why take chances? Content delivery service providers can get HD feeds in from the field and out to affiliates reliably.
A major challenge with HD news production is the fact that source content may be in a plethora of audio and video formats, all of which must be properly format-converted, transcoded or transrated for production and distribution. Video can arrive in 1080i, 720p, 480i, NTSC, IMX, P2, HDCAM, HDV and many other formats, while audio can be analog, digital, mono, stereo, 5.1 or others. It cannot be assumed that all feeds will be in a 16:9 aspect ratio. User-generated content from citizen-journalists makes matters worse. Whatever the source formats, they will have to be converted to the house production standard.
Intelligent leveraging of the inherent characteristics of source material may be possible. For example, consider windowing an SD source rather than upconverting to full screen HD or using a stereo source as left and right channels and supplementing the center and surround audio.
News segments often use historical footage in legacy formats. This poses a serious challenge when converting to HD news production. Money spent on equipment needed to convert legacy material for HD broadcasts may be more expensive than the depreciated value of the device.
It may be significantly more cost-effective to digitize and ingest content that has a high probability of use prior to its being needed for a segment. Or should equipment be kept on hand and operational for ad-hoc conversion as needed for a breaking story? An experienced systems integrator has probably faced these questions before and can discuss the merits of each approach based on your production workflows.
Graphics packages may now need to support two aspect ratios. Although existing graphics that were produced for SD may initially be used for HD broadcasts, at some time in the future, new graphics will need to be produced in HD.
WETA delivers its HD broadcast in a letter-box format for its SD viewers. This alleviates the need to consider framing content for a 4:3 center cut as NBC does. CNN tries to leverage the best of both worlds by creative integration of graphics and windowing that is visually appealing in both 16:9 and 4:3 aspect ratios. Regardless of the technique, the infrastructure must be designed for the frenzied newsroom production environment. Conversion steps must be minimized.
Audio requires special consideration. Even if a production has “gone digital,” it is still probably only producing stereo audio for SD resolution video. Dolby Digital encoding will be needed for program release. A decision must be made as to how audio should be formatted and distributed during production. Discrete and embedded audio require different distribution and processing techniques-.
Because viewers now have high-quality audio systems in their homes, consistent audio presentation is imperative across live studio and remote segments, preproduced clips and commercials. Changes in level and quality from segment to segment that were not previously noticeable are now glaringly obvious and annoying.
Differences in source volume levels can be a large problem in HD audio presentation. Appropriate Dolby metadata must be generated and included in the audio bit stream. This will require an upgrade in audio equipment and the added attention of audio production personnel. Monitoring becomes critical. (See the December 2007 Broadcast Engineering article “Dialnorm: A good idea gone bad?” for further background on the use of dialnorm in broadcast environments. The article is available at http://broadcastengineering.com/audio-/dialnorm_good_idea/index.html.)
Because many newsrooms have already migrated to a tapeless, file-based production workflow, one important consideration when converting the newsroom to HD is the increased requirement for network bandwidth and storage capacity. Regardless of the house compression format, HD data rates are considerably higher than SD. Expect to double or triple storage capacity and the network backbone bandwidth. The challenge is to develop a production workflow and infrastructure that maximizes quality and minimizes HD content data rates while staying within budget constraints.
Large HD files require greater bandwidth than SD files when sent over IT networks. A network that works fine during normal production may fail under the strain of a breaking news story, when double or triple the number of newsroom personnel are trying to access the content. This is when a failure or glitch will have the largest effect on production. Production delays could allow a rival to break the story first.
It's necessary to upgrade video servers to HD capability and significantly increase disk storage. Network bandwidth should be for HD file-based production. Deciding on a network and storage topology is also important. A key decision is whether to store content in a federated storage area network (SAN) with local proxy editing or employ local editing of full-resolution video as the preferred workflow.
Maybe the answer is both. An experienced systems design and integration firm can present viable system implementation options based on its experience. It can work with your in-house IT department to ensure the broadcast and production networks are properly integrated with the business and corporate network and applications. At this time of transition, knowledge of the particular needs of broadcast IT can be transferred to nonbroadcast technologists.
Physical considerations cannot be overlooked. New HD systems are more compact but are power hungry. This may strain the existing power and cooling infrastructure. It is also important to avoid placing racks and consoles against walls and in tight confines. Not only will they rapidly overheat, but access to the equipment will be difficult.
Signal distribution of HD-SDI at 1.5Gb/s requires significantly more care than SDI at 270Mb/s. Cable types and lengths become critical. Fiber will be needed for long connection paths. Observing bend radius specifications and proper splicing and termination is imperative. A lot of time can be lost tracking down marginally performing equipment only to find that the cabling is faulty. Compromised digital signal systems — HD in particular — have the disturbing characteristic of looking great right up until the point that they crash because of errors induced by poor cabling.
Many older pieces of equipment will not pass embedded Dolby or vertical interval time code (VITC) and other forms of ancillary data. This will affect the need to support both 608 and 709 closed captions. A broadcast facility will require an appropriate conversion system to support the HD workflow and the purchase of conversion equipment.
Monitoring systems must support Dolby and non-Dolby audio, as well as SD and HD video. Dolby E and AC-3 will have to be decoded at the test stations. This means purchasing upgrades or new systems and possibly additional interface devices.
The HD value proposition
Obviously, there is no one-size-fits-all solution for an HD newsroom upgrade. Each station has particular needs and workflows that must be carefully analyzed. Every station has budget limitations. Partnering with an experienced design and integration company enables the broadcaster to focus on the HD newsroom workflow. Converting to HD news production will probably be more expensive than the optimistic figures generally put forth. Consider whether these numbers are based on the current cost of SD versus HD equipment, or on the prices of SD equipment from years ago and now adjusted for inflation.
Your staff will have to learn how to use the new equipment and the nuances of producing in HD. Be sure to allow for adequate training and rehearsal time. HD workflows may be different, and the production staff will need to adjust its practices.
An infrastructure must perform flawlessly. For this reason alone, the use of an outside partner in the design and implementation process should be carefully considered.
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