Template:Interlaced Video
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- Interlaced Video
- display method that consists of drawing only alternating lines of video signal during a single display refresh cycle
- Example: Frame 1 of a video signal is broken up into many horizontal lines of pixels. Lines 1, 3, 5, 7... of the image are drawn by the TV during its first refresh cycle, which we'll call Frame 1a. At the TV's next refresh cycle, Frame 1b, it draws lines 2, 4, 6, 8... of Frame 1. It then draws lines 1, 3, 5, 7... of the next frame of the video, then lines 2, 4, 6, 8... and so on for each successive frame.
- common for analog video, especially over a Coaxial, RCA, or S-Video cable
- common resolutions include 480i (analog "Standard Definition" TVs), 1080i
- vertical resolution effectively halved because at any given moment only half the pixels in a given column are active
- refresh rate of the display is effectively halved
- video quality is blurry and faint compared to Progressive Scan
- unpleasant 'combing' pattern is sometimes visible in scenes with lots of action, horizontal motion, or fast camera panning
- de-interlacing can reducing appearance of 'combing'