Definitions for "Interlaced Video"
Keywords:  ntsc, pal, odd, television, scan
Interlaced video is scanned from right to left, top to bottom, in the same way as progressive scan video. The difference, though, is that every sixtieth of a second, every other line making up the complete frame is scanned. Then, a sixtieth of a second later, the lines in-between the lines already scanned are captured. Effectively, half the picture's vertical resolution is sent in the first sixtieth of a second, and the second half is sent in the second sixtieth of a second. When the video is played back, the whole thing happens in reverse, giving the appearance of a complete frame. Each of these "halves" of a frame is called a "field".
A technique used for television video formats, such as NTSC and PAL, in which each full frame of video actually consists of alternating lines taken from two separate fields captured at slightly different times. The two fields are then interlaced or interleaved into the alternating odd and even lines of the full video frame. When displayed on television equipment, the alternating fields are displayed in sequence, depending on the field dominance of the source material. See also progressive video.
A video frame format that divides the lines into two fields, each consisting of alternating odd and even lines, which are scanned at different times. Used in standard definition video.