Broadcasting Standards

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Broadcast Standards

Another group of standards combine technical and legal definitions. These are called ATSC, NTSC, PAL, and SECAM. ATSC
ATSC stands for Advanced Television Systems Committee, but the acronym is synonymous with the group's standard for digital television broadcast. ATSC is used for over-the-air transmission of HDTV signals, replacing the former analog standard NTSC. It can support video resolutions up to 1080p and 5.1 surround audio, and can be picked up on the same frequency UHF/VHF antennas as NTSC.
NTSC
NTSC stands for National Television Standards Committee, and is synonymous with the video transmission standard for North and Central America, including Mexico and Canada, and Japan. Its technical format is 525 lines per frame at roughly 30 frames per second refresh rate. The video is interlaced over the even and odd scanlines, for an apparent refresh rate of ~60fps. In quality, NTSC is equivalent to a composite signal. but is not necessarily equivalent to the output from a video capture card that may claim to be NTSC-legal.
NTSC is no longer utilized in the United States, having been replaced with the digital ATSC standard in 2009.
PAL
PAL (Phase Alteration Line) is the European counterpart to the NTSC standard. It has a higher vertical resolution (625 lines per frame) but a lower refresh rate (25 frames per second) that can cause flickering. It is the standard for the UK, Western Europe, the Middle East, and parts of Africa and South America.

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