576i

576i is a standard-definition digital video mode, originally used for digitizing 625-line analogue television that had been used in most countries where the utility frequency for electric power distribution is 50 Hz. Because of its close association with the legacy colour encoding systems, it is often referred to as PAL, SECAM or PAL/SECAM, when compared to its counterpart, 480i, commonly called NTSC after the system typically used in countries with 60 Hz utility frequency (see also PAL-M). The 576 identifies a vertical resolution of 576 lines, and the i identifies it as an interlaced resolution. The field rate, which is 50 Hz, is sometimes included when identifying the video mode, i.e. 576i50; another notation, endorsed by both the International Telecommunication Union in BT.601 and SMPTE in SMPTE 259M, includes the frame rate, as in 576i/25.