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Related to interlacing: Deinterlacing


A video display system which builds an image on the VDU in two phases, known as "fields", consisting of even and odd horizontal lines.

The complete image (a "frame") is created by scanning an electron beam horizontally across the screen, starting at the top and moving down after each horizontal scan until the bottom of the screen is reached, at which point the scan starts again at the top. On an interlaced display, even numbered scan lines are displayed in the first field and then odd numbered lines in the second field.

For a given screen resolution, refresh rate (frames per second) and phosphor persistence, interlacing reduces flicker because the top and bottom of the screen are redrawn twice as often as if the scan simply proceded from top to bottom in a single vertical sweep.


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To illuminate a screen by displaying all odd lines in the frame first and then all even lines. Interlacing uses half frames per second (fields per second) rather than full frames per second.

The interlace method was developed for TV broadcasting because the allotted bandwidth for TV channels in the 1940s was not sufficient to transmit 60 full frames per second. It was decided that interlacing with 60 half frames was visually better than 30 non-interlaced full frames.

Interlace vs. Progressive Scan (I vs. P)
Interlaced screens display odd lines first: 1-3-5, etc.; then even lines: 2-4-6, etc. Non-interlaced "progressive scan" screens display lines consecutively: 1-2-3-4-5-6, etc.

All old tube TVs (CRTs) were interlaced. Very old CRT computer monitors were interlaced at their highest resolution and progressive at lower resolutions. Today, some digital TV standards are interlaced, such as the high-definition 1080i format, and 1080i material is commonly transmitted by the TV networks. HDTV sets support both interlace and progressive scan methods (see HDTV and DTV). See deinterlace, vertical scan frequency, 4K 3D TV and interlaced GIF.

The Difference
In one second, interlacing displays 30 sets of odd lines and 30 sets of even lines, resulting in 60 fields per second. For every half frame of interlaced scan, progressive scan displays a full frame. Modern DVDs and monitors convert the 60 fields in interlaced NTSC content to 60 frames by interpolating the missing lines.
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Heberlein PolyJet SP-2 HP provides high-performance air interlacing for filament spinning applications
Two-level interlacing is as follows: interlacing by rows first and then by columns (or in the opposite order) to get four subimages: even rows even columns (EE), even rows odd columns (EO), odd rows even columns (OE), and odd rows odd columns (OO) as shown in Figure 10.
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To illustrate these three central points (the innovative structure and semantics of the Furioso and their function as response to historical crisis), I will focus on canto 17, which offers a particularly interesting example of interlacing several different formal elements.
Recently patented is a wiping sheet that is made of at least one nonwoven fabric formed by interlacing fibers containing thermoplastic fibers.
Piecing together the interlacing roles of the myriad new genes presents a massive puzzle, yet many of the pieces are familiar.
text Medieval Latin textus, from Latin, interlacing, makeup, structure, a derivative of texere to weave, construct
Interlacing twigs, grasses and roots apparently inspired countless geometric and abstract shapes, while other patterns exhibit scenes reminiscent of surrealistic modern art.