HDTV - A Brief Overview
HDTV (high definition television) is the new standard in television technology, which provides wide-screen picture quality similar to 35mm film along with compact disc (CD) sound quality.
HDTV is part of several standards incorporated in digital television or DTV. Basically, DTV is composed of three separate standards:
Although the ATSC defines both 1080 lines and 720 lines as HDTV, there are differing views with respect to how HDTV should be defined.
HDTV has been available on a regularly scheduled basis to viewers in Japan via analogue satellite transmission on NHK Television since 1990. United States major market television stations began transmitting DTV in the fall of 1998. The number of new DTV stations on the air is increasing every month. By the year 2008, all United States television stations will be converted to DTV.
HDTV is the biggest breakthrough in broadcasting since color TV. It offers wider pictures with greater detail and the clarity of motion pictures. Compared to standard television (NTSC), the true HDTV image has twice the luminance definition - vertically and horizontally - and is twenty-five percent wider.
Standard television aspect ratio is 4:3 (four units wide, three units high) - the HDTV aspect ratio is 16:9. The 16:9 ratio is much closer to the average wide-screen image shown in movie theaters. The biggest difference, and the greatest appeal of HDTV, is its clarity. True HDTV pictures are composed of 1080 active lines (1125 total) whereas current standard television pictures are composed of only 486 active lines (525 total).
While it is possible to see the lines that make up standard television pictures, HDTV lines are not at all noticeable. The fine-grained HD picture contains five times more information than does the standard television picture and is accompanied by multi-channel, CD quality sound. The difference in video and sound quality is dramatic.
Currently there are 610 digital television stations on the air and an equal number of stations that have applied and received a construction permit for erecting a DTV transmission tower. For the complete list see the following Internet web site address: www.hdpictures.com/stations2.htm.
For current weekly listings of HDTV programming being broadcast go to: www.hdtvgalaxy.com.
Copyright © 2005-2006, Marc W. McCord dba CobraGraphics. All rights reserved. CobraGraphics, Lone Star Paddler, canoeman.com, Southwest Paddler and Canoeman River Guide Services are exclusive tradenames and trademarks of Marc W. McCord dba CobraGraphics. Wilderness Explorations Inc. is the exclusive tranename and trademark of Marc W. McCord and Dirk Davidek. The textual, graphic, audio, and audio/visual material in this site is protected by United States copyright law and international treaties. You may not copy, distribute, or use these materials except for your personal, non-commercial use. Any trademarks are the property of their respective owners. All original photos on this web site are the exclusive property of Marc W. McCord, Dirk Davidek or other designated photographers and may not be copied, duplicated, reproduced, distributed or used in any manner except upon prior written permission under penalty of US and International laws and treaties.