- published: 17 Feb 2015
- views: 358330
Low-definition television or LDTV refers to television systems that have a lower screen resolution than standard-definition television systems. The term is usually used in reference to digital television, in particular when broadcasting at the same (or similar) resolution as low-definition analog TV systems. Mobile DTV systems usually transmit in low definition, as do all slow-scan TV systems. This is also occasionally referred to as North Korean HD.[citation needed]
The most common source of LDTV programming is the Internet, where mass distribution of higher-resolution video files could overwhelm computer servers and take too long to download. Most mobile phones and portable devices such as Apple’s video iPod, or Sony’s PlayStation Portable use LDTV video, as higher-resolution files would be excessive to the needs of their small screens (320 × 240 and 480 × 272 pixels respectively). The current generation of iPods (excluding the 4th Gen iPod Touch) have LDTV screens, as do the first three generations of iPhone (480 × 320).