HDTV means high definition television. HDTV is a video and television standard that includes a group of formats, or modes, which all provide higher resolution than previous standards (now referred to as SD or standard definition).
There are three main differences in the types of HDTV modes available:
- Pixel resolution: The number of pixels per frame (the more the better).
- Interlacing format: Either interlaced (each frame consists of two half-resolution fields) or progressive (each frame contains a full resolution image).
- Frame rate: Each HDTV mode can be specified with various frame rates (the more frames per second, the better).
The three HDTV modes are:
- 1080i : 1920x1080 pixels interlaced
- 1080p : 1920x1080 pixels progressive
- 720p : 1280x720 pixels progressive
For audio, HDTV uses Dolby Digital surround sound (AC-3).