480i
480i is the shorthand name for a video mode, namely the US NTSC television system or digital television systems with the same characteristics. The i, which is sometimes uppercase, stands for interlaced, the 480 for a vertical frame resolution of 480 lines containing picture information; while NTSC has a total of 525 lines, only 483 of these are used to display the image for DV-NTSC. Its PAL/SECAM counterpart is 576i; together, these are the two common forms of standard-definition television.
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