The Fjelstad interview says FC inside
the professional video studios.
Here are some things that relate to this.....
The tools that allow the studios to search
for just the right picture will
help make the shift to digital video
and FC will haul it.
Wouldn't you like to do a search on
the web like this........
A company may have miles of video tape, but if you don't know what's on it or how to find what you need, it's almost worthless. These media asset-management tools will help you put your video house in order.
newmedia.com
The video studios are at a critical point. FC to the rescue?
Where is that FC-ATM interface?
This area has no legacy, will have a big need for SAN,
and could catapult FC into the limelight.
techweb.cmp.com
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In building a complete DTV chain, including image capture, program production and transmission, "we are just scratching the surface now," cautioned consultant Weiss, who also serves as co-chairman of a joint task force formed by the Society of Motion Picture and Television Engineers (SMPTE) and the European Broadcast Union. "We need to figure out where holes exist, which connectivity [between what boxes] is still a dotted line, and how we can make it a solid line."............................
Missing from the current crop of specifications is a broad array of issues. They include connectivity between networks and their affiliates, interfaces between TV stations and their DTV transmitters, a master and control scheme for a variety of systems within a TV station, a monitoring system to test the integrity of signals at various phases in the DTV program production and transmission chain, and a standard way of routing compressed bit streams inside a digital TV studio.
The complexity of replicating the entire TV production infrastructure in the digital domain "will shape and affect the nature of DTV rollout," said Michael Gold, senior research engineer at SRI Consulting (Menlo Park, Calif.). The transition to digital involves undefined steps, such as how to pass through network feeds to affiliates; how to do local insertions; and how to locally produce video. "Local DTV production will be an end game," said Gold.
The two-day meeting was broken into separate sessions that explored the interfaces required at various segments of DTV studios. They include video and audio signals, data and accompanying metadata, control, timing and monitoring. "We went through as many interfaces as we could," said Weiss.
The outcome of the debate over standard interfaces could have far-reaching implications for digital broadcasting and for decisions networks and their affiliates must make in planning their DTV plant architecture.
For example, the ATSC standard specifies 18 different video-transmission formats for final distribution of DTV programs between TV stations and receivers. But no industry standards exist that specify bit rates and modulations of network feeds between studios and affiliates.
As a result, each network is building proprietary specifications for its signal-transmission systems and receivers. According to its vice president of engineering, Robert Seidel, CBS may send its digital HDTV programs to its affiliates at 45 Mbits/second using DS3 links via a 36-MHz satellite transponder. Meanwhile, other networks may decide to send their affiliates a 19-Mbit/s digital video stream, pre-compressed according to the ATSC transmission standard, as their pass-through network feed.
As a result, one network's proprietary receiver may not be able to receive certain DTV programs syndicated by another network.
Another critical interface still missing from the ATSC standard is how to route compressed or uncompressed signals within a DTV plant. The ATSC "has not specified how to move MPEG streams around in a studio," said Al Kovalick, strategist for technology and standards at Hewlett-Packard Co. (Palo Alto, Calif.).Where is that Vixel-HWP announcement
Some stations, like CBS, may opt for routing uncompressed digital high-definition video at 1.5 Gbits/s using Sonet to maintain the best-quality video for production. Others may use, for intermediate distribution and storage, a low-level mezzanine compression - ranging from about 60 Mbits/s to a low of 38.78 Mbits/s. The lack of industry consensus on low-level mezzanine compression makes it difficult to connect different servers and routers in a DTV facility, Kovalick said. The issue is under study by SMPTE.
Digital audio is even less well-defined. Many broadcast engineers agree that Dolby Digital was never intended for post-production applications within a studio. "It is so highly compressed . . . it's just not robust enough for that kind of application," said Philip Livingston, director/general manager of digital systems at Panasonic Broadcast & Digital Systems Co. (Secaucus, N.J.). Dolby and others are examining "how much headroom should be allowed if the audio needs to go through a concatenation of compression and decompression," said Sarnoff's Smith.
Interface issues in the command-and-control segment are another largely unresolved area. Still unknown is how, within a studio, to send instructions to control 10 to 20 streams going through sophisticated encoders and statistical multiplexers. Today, each encoder and multiplexer comes with a separate terminal to control its proprietary interfaces. With no standard interface, the worst-case scenario is that different device drivers must be developed for every encoder system.
"Monitoring and testing the integrity of signals that are moved around inside a studio" is another interface issue, said Smith. Ideally, where monitoring systems are needed should be determined first so that signal-quality spec conformity can be ensured at each point in the DTV plant. "The issue is more to do [with] whether such testing equipment exists today and who [is] building them," Smith said.
Some engineers attending last week's meeting expected "a major showdown" with ATSC. They had predicted that crucial last-minute modifications to the ATSC specifications - including the table of 18 video formats-might be offered...............................
They don't have much time to settle these issues, so they need stuff off the shelf.
With so much to be decided settling on FC would allow them to focus on some of the thorny issues. Any thoughts out there?
NAB should be interesting. |
