What is High Definition Television (HDTV)?
HDTV is a name given to two of the digital television (DTV) formats. HDTV provides high resolution programming. A current analog TV picture is made up of horizontal lines on the picture screen; an HDTV picture can have more than twice as many lines, allowing for stunning picture detail. HDTV uses a “widescreen format.” “Widescreen format” refers to an image’s aspect ratio, which is a comparison of screen width to screen height. Analog television has an aspect ratio of 4 by 3, which means the screen is 4 units wide by 3 units high. The aspect ratio of HDTV is 16 by 9, similar to a movie theater screen. HDTV programs can include Dolby Digital surround sound, the same digital sound system used in many movie theaters and DVDs. HDTV uses the same amount of bandwidth (the size of the communications channel) as the current analog system, but with HDTV, about six times more information is transmitted. This capability translates to much better quality in picture and sound.
High Definition Television is a type of digital television that uses extremely high-resolution imagery with enhanced audio (such as Dolby Digital) to provide a movie-theater like viewing experience. The number of horizontal lines (made of pixels) displayed on the TV screen determines the TV resolution. High-definition TVs have 720 horizontal lines or more, as compared to traditional analog televisions, which have 480 horizontal lines. There is also a difference in the screen format (or aspect ratio) that gives high-definition TVs the ability to display a wide screen format (or 16:9 aspect ratio) while traditional TVs utilize a 4:3 aspect ratio. High-definition TVs can be purchased at local electronics stores and look similar to traditional analog televisions, but provide a picture that is six times sharper than an analog TV set.
• Digital television allows stations to broadcast programs in much higher resolution or clarity than standard analog television. This is called high definition television or HDTV. Viewers at home are able to receive high-quality, crystal-clear pictures. These visually stunning pictures, with more than twice the resolution and clarity of standard television, are displayed in a wide screen format with a 16:9 width to height ratio compared to analog’s 4:3, or almost square format. And because HDTV is digital, audiences have the benefit of six-channel CD-quality “surround sound.” In other words, viewers are able to enjoy a true home theater experience. HDTV normally provides 720 or 1080 lines of resolution (depending on format) vs. 480 lines on standard definition.
What is High Definition Television (HDTV)? Answer: High definition (HD) is at the top of the digital television (DTV) spectrum. The reason is simple – resolution. The Advanced Television Systems Committee (ATSC) divided HD into three categories listed in two different forms – ‘number of lines + type of scan’ or ‘number of pixels’ (vertical by horizontal). Here is a breakdown of the HD formats listed by how manufacturers label them on their product summaries: • 720p or 720×1280 – 720 lines, progressive scanned • 1080i or 1080×1920 – 1,080 lines, interlaced scanned • 1080p or 1080×1920 – 1,080 lines, progressive scanned The number of lines/pixels and type of scan matters because more lines/pixels and faster scan equals a better picture. In ranking the HD signal formats, 720p and 1080i are virtually equal in overall resolution while 1080p is the best. What Do You Need For HDTV?
