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.
An analog video signal consisting of alternating odd and even fields.
Interlaced video is where each frame of the video is divided into two fields. The first field is called the upper field and contains the topmost horizontal scan lines of the frame. The second field is called the lower field which contains the lowermost horizontal scan lines of the frame. A Television displays the all the upper fields first, and then displays all the lower fields in order to fill in the alternating gaps left by the upper fields. One NTSC video frame which is displayed approximately every 1/30th of a second, contains two interlaced fields, displayed approximately every 1/60th of a second each. PAL and SECAM videos display frames at 1/25 of a second and contain two interlaced fields displayed 1/50th of a second each.
The process by which two separate video fields form a television picture. In the NTSC format, the field consisting of the odd-numbered lines is drawn first, followed 1/60 second later by the field with the even-numbered lines. Although the two fields don't actually appear at the same time, the human brain interprets them as a single frame lasting 1/30 seconds.
A system where each frame of video has two fields of odd and even lines, which are shown rapidly so that the viewer sees a single, integrated image.
Video that is created by interlacing (interweaving) to consecutive pictures to create a single picture. In interlaced video, the first field is painted into every other line of the video display screen. The second field is then painted into the lines left blank.
Each PAL video frame consists of two fields. When displaying video, a PAL television displays one field every 1/50 of a second. Our eyes put the two alternating fields together to create 25 whole PAL frames per second. This effect is undesirable for multimedia applications and should be removed (de-interlaced) prior to compression.
Process of scanning frames in two passes, each painting every other line on the screen, with scan lines alternately displayed in even and odd fields. NTSC video is interlaced; most computers produce a noninterlaced video signal. [See noninterlaced video
Each NTSC or PAL video frame consists of two "fields". When displaying video, NTSC televisions display one field every 1/60th of a second, and PAL televisions display one field every 1/50th of a second. Our eyes put the two different fields together to create 30 whole NTSC frame per second.
Each NTSC or PAL video frame consists of two "fields". For example NTSC televisions display one field every 1/60th of a second, and our vision puts the two different fields together to create 30 whole NTSC frame per second.
