Digital transmission of television will change the way people watch and use television like no other advance has. Among the technological advances in television that will be possible with digital TV are
- Digital clarity (picture and sound)
- Program guide
- Multicasting and datacasting
Evolution of TV technology
Digital transmission of television is part of an evolution of technological advances that began over 60 years ago. Color TV was an improvement to black & white TV and the technology maintained compatibility. Digital transmission overcomes the limits of analog, but the systems are not compatible. TV technology has evolved and change is upon us.
Most people are familiar with how compact discs (CD's) revolutionized music. Analog sources, such as tapes and LP records, degrade with use and eventually develop noise problems. Digital technology changed that by offering an exact match to what was recorded onto the Master CD at the studio. Digital TV offers a similar benefit to both picture and sound on television. When tuning a digital signal, you get the same clear picture and sound that was captured in the studio - with none of the ghosting or snow that we're used to seeing in over-the-air analog broadcasts.
High Definition TV can be carried on digital TV transmissions. HDTV offers a much higher resolution picture and sound than standard or conventional television broadcasts. HDTV picture resolution is even better than DVD's with the same high-quality digital sound as DVD's. HDTV programming is also "widescreen."
HDTV vs. DTV
Digital TV or DTV is a transmission method - sending television over the airwaves digitally. HDTV can only be carried on and viewed through DTV transmissions.
Free HDTV programming
The four major networks all offer HDTV programming broadcast for free over their affiliates' DTV over-the-air transmissions. The only way to see this free programming in high definition in the mid-south is by tuning in the digital signal using an antenna and DTV receiver.
Data in the digital stream
Digital TV also allows stations to broadcast non-television data in their DTV signals. This data can be used for many purposes.
One promised use of data in the DTV signal is a program guide. Similar to the program guides used on cable TV or satellite systems, this guide can provide program times, information, and ratings. Currently, only channel information is available on WPTY-DT 24 and WLMT-DT 30 with program information soon to be offered. Your DTV tuner will receive and display this guide information for free.
Digital TV allows stations to broadcast multiple programs on one channel. Each digital channel can potentially hold six "sub-channels." Broadcasters can use this capability of DTV to broadcast multiple programs at the same time. For example, a station could continuously broadcast local news, weather, and traffic programming on sub-channels.
A DTV broadcast sends the equivalent of two floppy disks full of data to your tuner every second. That's 7,200 floppy disks per hour, 24 hours a day! One possible use of DTV is something called "datacasting." Stations can broadcast news, weather, sports scores, stock prices, consumer information, etc. to appear on your TV or routed to your computer or other devices. Datacasts will "piggyback" on the DTV television signal. So, you will get digital television and data.
The future of television is here
As you can see, DTV goes well beyond the capabilities of analog television. DTV is the future of television and much more. With multicasting and HDTV being broadcast regularly in the mid-south, the future of television is here now.
*some material provided courtesy of AtlantaDTV.org