HDTV Technology

HDTV is really a combination of technologies, all employed to produce high-quality picture and sound.

Digital transmission - All HDTV signals are encoded and transmitted digitally, with a series of binary bits. This results in exact fidelity to the original programming source.

Higher resolution - A standard definition television (SDTV) picture is composed of approximately 300,000 pixels. The HDTV picture is composed of either 921,000 or slightly more than 2 million pixels, for more than three times the picture information of standard television. This results in a much more detailed, almost lifelike picture.

Digital video compression - To fit the increased pixels of the HDTV picture into the allotted bandwidth, MPEG-2 digital compression is used to fit more bits into the same amount of space. Only changed parts of the picture are encoded, and redundant bits of the picture are not transmitted.

Widescreen display - SDTV utilizes a squarish 4:3 ratio screen, which is ill-suited for viewing widescreen movies. HDTV uses a 16:9 ratio widescreen display -- perfect for movies and other widescreen programming.

Digital surround sound - Our current analog television system allows for analog stereo sound, with rudimentary Dolby Pro Logic surround sound. The HDTV system incorporates the state-of-the-art Dolby Digital surround sound system, with pristine digital sound reproduced in a 5.1-channel system.

Michael Miller is a writer and commentator on technology and digital lifestyle topics.