Expanding the Hi-Def Skies

Satellite operators, programmers embrace MPEG-4 compression
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Lower high-definition TV set prices, more affordable production gear and improved transmission technology were the big topics for satellite operators, programmers and vendors at the ISCe Satellite Investment Symposium (ISIS) and the joint HD World/SATCON conferences in New York last week.

“The stage is set for an HD explosion,” declared Jeffrey Friemark, chief financial officer of satellite giant Intelsat, to a crowd of satellite operators and investors at the ISIS event.

The technological challenge—and opportunity—is creating and using new advanced MPEG-4 compression gear that optimizes satellite and cable transmission paths.

HBO Chief Technology Officer Bob Zitter was on-hand at ISIS to discuss HBO's plan to move its 26 premium cable networks to hi-def by mid-2008.

To make the switch, HBO is converting the compression technology it uses for satellite feeds from the MPEG-2 standard to MPEG-4 advanced compression technology, using encoders, modulators and integrated receiver/decoders from Motorola. It will maintain primary HD feeds of HBO and Cinemax in MPEG-2 to serve its current base of legacy HD receivers for those channels.

“Television, going forward, is hi-def, and that's what it will be,” says Zitter. “That's the reason we decided we needed to make the gigantic leap that we did.”

While MPEG-4 has some obvious bandwidth efficiencies over MPEG-2—most vendors say it can produce the same picture quality in half the bitrate or less—HBO's commitment to MPEG-4 is a bold move because the existing universe of cable set-top boxes is MPEG-2. Zitter equates the decision with HBO's original gambit to switch its satellite feeds from analog to digital MPEG-2 in the mid-90s. It took the industry a few years to catch up.

“In the long run, it's going to happen,” says Zitter, who notes that cable operators are beginning to roll out dual-chip boxes that can receive and decode both MPEG-2 and MPEG-4 signals. Such boxes would allow HBO to pass an MPEG-4 feed directly from its transmission center to a cable subscriber's set-top with no extra compression steps.

Motorola has worked with HBO to create an interim solution for cable operators who want to carry the new HD channels now: an integrated receiver/decoder that is capable of receiving an MPEG-4 signal and transcoding it (actually, it decompresses and re-encodes it) to MPEG-2. That way, HBO can reap the satellite transponder savings of transmitting HD video at 9 megabits per second using MPEG-4, while a cable operator can still deliver an MPEG-2 feed at 18 Mbps, which can be displayed by current set-tops.

Cisco's Scientific-Atlanta unit is working on a similar solution, which should be available early next year, and both S-A and Motorola were on the HD World floor demonstrating how MPEG-4 content can be quickly transcoded to MPEG-2. These receiver/transcoder devices are also capable of taking an MPEG-4 HD feed and putting out a standard-definition MPEG-2 feed, which could give programmers the luxury of outputting a single HD feed to serve multiple delivery platforms.

“Customers are saying, 'Give me one box that does all of those things,'” says S-A product manager Joel Orvis.

While some major programmers warn that MPEG-4 compression technology is still far from being optimized, it has already gained significant traction in the industry. Satellite operator DirecTV is using MPEG-4 for its new HD program feeds, and telco AT&T distributes MPEG-4 signals for its U-verse TV service; both operators have rolled out MPEG-4-compliant boxes to receive them.

Satellite operators like SES Americom are delivering MPEG-4 standard-definition feeds to telcos and MPEG-4 hi-def feeds to cable and satellite operators as well as telcos. Of the 61 hi-def feeds SES carries, 27 are in MPEG-4, says Bryan McGuirk, president of media and enterprise services for SES Americom. The rest rely on MPEG-2 compression.

The proportion of MPEG-4 HD feeds that SES and other satellite operators carry will gradually surpass the existing MPEG-2 base, says Motorola senior director of marketing Marty Stein.

“Everything new in HD will be in MPEG-4,” Stein says.

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