More microwave mayhem?
Earlier this month, consultant and industry veteran Tore Nordahl released a new report analyzing the issues stations will face as they initiate HD ENG operations over the coming years.
His 98-page report, “HD ENG News Technology for TV Stations,” offers insight on HD ENG camcorders, compression and point-to-point microwave technology that must be considered while planning for HD news acquisition from the field.
This month, HDTU turns to Nordahl for perspective on HD ENG operations.
HD Technology Update: Only a handful of TV stations currently acquire HD footage from the field for their newscasts. The conventional wisdom is that HD ENG is too expensive. Yet you recently published your “HD ENG News Technology for TV Stations” report. Does that indicate the equation is changing and HD ENG operations are becoming practical and affordable?
Tore Nordahl: Yes, with qualifications. From a competitive position in a market, the television station that can initiate HD news is very likely to grab a larger share of viewers who are part of the newer installed base of households with HD sets. If you look at it — and say if you don’t go HD news within a couple of years — the probability is you will lose market share. If you do go HD, you will probably gain market share. What remains is answering the question: When is the right time for TV stations to make the investment for HD ENG. We believe it is sooner rather than later.
One of the reasons for the report is to discuss and analyze what is a reasonable cost for an HD ENG camcorder. What do we need as far as size of CCD or CMOS to make high-quality images for HD? What cost efficient technology is available to the HD camcorder manufacturers? What can they (manufacturers) do if pressured by the market? If everyone says: ‘I’m happy to buy a $40,000 HD ENG camcorder,’ that’s what the market will get. But if buyers are a little more selective and put more pressure on the manufacturer for a more cost-efficient product, you will see those.
If you compare the major ENG investment for SD 10 years ago when moving into digital ENG at that time, you might actually see the HD ENG investment in 2006 and beyond will be less due to a significant drop in digital video cost vs. performance.
Get the TV Tech Newsletter
The professional video industry's #1 source for news, trends and product and tech information. Sign up below.
HDTU: Will the HDV format play a part in local HD ENG?
TN: I’ve certainly seen some very good pictures captured and played back by HDV camcorders. HDV technology is suitable for early HD ENG testing, but not for long term HD ENG operations. You have to look at two specific areas. The size of the CCD or CMOS imagers — and I still think a 1/3in CCD image is not sufficient for the typical ENG operation from a sensitivity point of view.
The second area is the compression being used. Sony is using MPEG 2 15-frame GOP (group of pictures) and JVC is using an MPEG-2 six-frame GOP system. This is an important area to analyze in ENG, which is live. You would like to reduce the total delay from the point of capture, where the shooter is out with the reporter, through the return path to the studio by reducing the delay in the encoding and decoding phase. With 15-frame GOP MPEG 2, you are looking at a delay in the encoding and decoding that may not be acceptable to some ENG operations. If you look at the six-frame GOP from JVC, you have a lesser delay but still a significant delay.
I think what the report does is to look at the compression schemes and ask what we as an industry have done in the past. WRAL (in Raleigh-Durham, NC) got into full HD — virtually full HD news operation in 2001 — with Panasonic DVCPRO HD. Panasonic DVCPRO HD’s intraframe compression offers real-time encoding without significant delay. Intraframe is what we want, not GOP.
The total bit rate of DVCPRO HD and Sony’s HDCAM is over 100Mb/s in the compressed state, and going back to a truly live ENG situation, there is not enough microwave bandwidth available in any band to transmit this back to the station.
If you look at digital modulation schemes for microwave you find you can have reliable connections up to 60Mb/s, which would require up to a 25MHz channel bandwidth. With the 2GHz BAS relocation, that bandwidth is being reduced to 12MHz. The only available bandwidth to support a 25MHz channel for 60Mb/s transmission is at 7GHz and 13GHz. We believe HD ENG needs to happen in the 7GHz band.
Both the Sony HDCAM and the Panasonic DVCPRO-HD compression schemes are very good, but, frankly, both are old and we can now do much better. With the newer compression technologies, like the intraframe wavelet scheme being employed by the new Motion JPEG2000, which has been adopted by the Hollywood movie studios for digital cinema, you can achieve a picture quality equivalent to DVCPRO-HD and HDCAM at about 50Mb/s to 60Mb/s.
HDTU: So what you are saying is that the commission-mandated 2GHz relocation plan and all of the effort being made to replace microwave transmitters and receivers and pack ENG transmissions into the 2GHz band with 12MHz channels ultimately will be unsuitable for sustaining the HD quality stations will want from the field — even with new generation compression approaches?
TN: I don’t know that much about the politics behind the BAS relocation. We are simply looking at it from a technical point of view.
TV stations should seriously look at the 7GHz band because the channel band available there is 25MHz, and that is what they need to transmit real-time compressed HD back to the studio in an easy to use intraframe scheme. And we are making that recommendation. Real live HD ENG operations as well as TV studio HD operations will benefit greatly from intraframe compression.
TV stations and the TV broadcast industry as a whole may need to standardize on two different compression schemes by 2007. One needs to be intraframe wavelet for HD ENG and HD news studio, and the other a transport compression scheme, likely to be H.246 AVC, which is a highly efficiently long GOP compression scheme. Those two will be selected by the television industry, we believe, within the next couple of years.
HDTU: So how should stations approach HD ENG from a budgeting point of view?
TN: Be cautious. Don’t spend a lot of money now till you know what you’ll require to be competitive in your market, so you don’t fall behind the technology curve. Plan and experiment in 2005, decide in 2006 and implement HD news no later than 2007.
For more information on the report, visit www.nordahl.tv.