Digital TV relies on a compression and encoding scheme known as MPEG-2 to fit its stunning images into a reasonable amount of bandwidth. In each image, the MPEG-2 software records just enough of the picture without making it look like something is missing. In subsequent frames the software only records changes to the image and leaves the rest of the image as-is from the previous frame. MPEG-2 reduces the amount of data by about 55 to 1. MPEG-2 already is the industry standard for DVD videos and some of the satellite TV broadcast systems.
Compression reduces image quality from what is seen by the digital camera at the studio.
However, MPEG-2 is very good at throwing away image detail that the human eye ignores anyway. The use of MPEG-2 permits a HDTV receiver to interact with computer multimedia applications directly. For example, a HDTV show could be recorded on a multimedia computer, and CD-ROM applications could be played on HDTV systems. A Digital TV decodes the MPEG-2 signal and displays it just as a computer monitor does, giving it high resolution and stability. Inc. All rights reserved.