Wednesday, May 16, 2007

HDTV, Mulitcasting & More

The best feature of DTV is the signal. A digital signal is not affected by noise or either get it perfect or not at all. Even a digital signal from a cable box or satellite receiver has a better quality look than an analog signal. But DTV offers more...higher quality video, more choices and interactivity.

HDTV gets all the buzz and is often mistaken as being the only benefit of DTV. That said, it is the most dramatic change to television.

An HDTV signal is the highest quality DTV signal possible, available in 2 formats 1080i or 720p. Both fill a 16:9 widescreen. The numbers represent the lines of resolution and the "i" stands for interlaced scanning and the "p" stands for progressive scanning. Interlace is a traditional television format and in HDTV some folks content it, with the higher resolution, gives the picture an almost 3-dimensional look. Progressive scanning has traditionally been a format used in computers and is supposedly better at handling fast motion and graphics. Either format stands apart from the normal 480i lines of resolution in a 4:3 screen. When mated with 5.1 Dolby surround sound there is a theater-like experience.

Another feature of DTV is a station's ability to broadcast multiple program feeds on one channel of television. Generally speaking a 6Mhz channel of television could have up to 6 programs feeds. Stations that offer one feed in HDTV really do not have much bandwidth for more than one additional channel. A lot depends on the motion video requires more bandwidth than static or slow moving video. There are expensive systems that manage bandwidth allowing stations to squeeze as much from their 6Mhz assignment...WWNY-DT does not have one of those systems at the present time.

WWNY-DT does multicast. On channel 7.1 we offer WWNY's CBS programming in 1080i HDTV. Not all programs are originated in we "upconvert" standard video to that format. One tell-tale sign of an upconverted program is that it is not as crisp looking and is not in the 16:9 screen format.

On channel 7.2 WWNY-DT offers a standard definition (480i/4:3) digital feed of the programming of WNYF FOX-28. We think this service is of value for a couple of reasons. WNYF analog is a low-power station with a limited service area. As a multicast channel on WWNY's digital signal, our service area is extended. The other reason is WNYF, as a low-power station, does not currently have a digital frequency and is not mandated to broadcast digitally. Multicasting on WWNY's signal provides viewers who invested in a digital television an additional digital channel to view.

Post 2/17/2009 WNYF does plan to broadcast digitally, even in HDTV*. We have applied for a license that will increase our service area over the current analog service area, but as a licensed low-power station it still will not have the range of WWNY-DT a full-powered station.

Another feature of DTV is that station's broadcast an Electronic Program Guide (EPG). You may be familiar with an EPG from cable or a satellite service. You can "interact" with the guide to see what's on, what's coming up, get a storyline description, determine the content rating, etc.

Other services are being explored by stations. You might be able to use a multicast channel to download the local newspaper, download music files for your I-Pod...perhaps even use your remote for polling, contests, and on-line purchases. As broadcasters stuggle to survive in this multichannel, DVR, I-Pod are bound to see new features and business models.

More info on HDTV, Multicasting and the transition from analog broadcasts to digital:
FCC Consumer Facts

* Of note: WNYF does not currently broadcast over-the-air digitally in HDTV. As noted above the feed is available digitally as a multicast channel of WWNY-DT in standard definition. WNYF does, however, feed Time Warner subscribers an HDTV feed. It is available on TW channel 878.

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