 
Anamorphic — Content that is enhanced for widescreen (16:9) televisions through the inclusion of increased vertical picture information. A widescreen television stretches the picture horizontally to match the increased vertical picture information, resulting in a clearer and sharper picture intended to be displayed only on a widescreen TV. Since a standard screen TV must letterbox widescreen images to fit them to the screen, much of the vertical resolution is lost. Widescreen television do not need to letterbox these images, and therefore can offer up to 33% more vertical resolution while viewing the same anamorphic DVD.
Aspect Ratio — The ratio of a picture's horizontal resolution, measured in either pixels or lines, to a picture's vertical resolution, also measured in either pixels or lines. Aspect ratio is always measured in width to height (e.g., 16:9). Standard screen televisions have an aspect ratio of 4:3. Widescreen television have an aspect ratio of 16:9 and allow for a more panoramic viewing experience.
Component Video — A set of three physical connectors (typically red, green, and blue RCA jacks) that are used to transmit or receive component video signals. Component video signals are high-bandwidth signals that separate the Luminance and Chrominance signals of a video picture for enhanced resolution and color fidelity.
Direct View Display — A direct view television uses a cathode ray tube (CRT) to produce picture images on the display screen. Three electron guns at the rear of the television fire beams at the phosphor-coated interior of the display screen. Each gun causes the phosphor to glow red, blue or green, causing a colored dot to appear on the screen. Since direct view displays are phosphor-based, they are susceptible to screen burn.
Downscaling — A process by which a program is converted to a lower resolution than its native format for display on a television. The process may also involve a conversion between progressive and interlaced scan formats. Downscaled content is typically less crisp and clear than its native resolution.
DTV — Television signals that are recorded, broadcast, and processed digitally. Currently, 18 different DTV formats have been specified, including SD and HD formats. DTV broadcasts are sharper than analog broadcasts and offer much better noise immunity and resistance to degradation.
DVI — Digital Visual Interface. This is a high-bandwidth video connection that carries digitized RGB picture information and can support copy-protection methods. The DVI specification allows for the presentation device and display device to agree on an optimal picture size and resolution to ensure the highest quality picture automatically.
EDTV — DTV signals that feature roughly the same resolution as SDTV signals but are drawn exclusively using progressive scan methods. Since these signals do not offer the additional resolution, they are not considered HDTV. But, because they offer a smoother picture and less flicker than interlaced SDTV signals, they are referred to as Enhanced Definition signals.
Field — As it relates to a video image on a television screen, a field, is comprised of one half of the complete picture frame - either all of the odd lines of a frame or all of the even lines. Two fields make up a complete video frame. (See Interlaced Scan)
Frame — As it relates to a video image on a television screen, a frame is comprised of all of the horizontal and vertical pixels (lines) at one time. A complete picture is known as a frame. (See Interlaced Scan, Progressive Scan)
HDTV — DTV signals that feature greater vertical and horizontal resolution compared to SDTV signals and are presented in a widescreen (16:9) format. HDTV pictures have twice the color resolution and roughly six times the sharpness of SD images.
Interlaced Scan — A method of drawing a picture frame on a television screen using two fields. One field is comprised of all of the odd-numbered lines on the screen, and the other field is comprised of all of the even-numbered lines on the screen. An interlaced picture is created by drawing all of the lines in one field first, then drawing all the lines in the other field second.
Letterbox Mode — A method of presenting widescreen images on a standard screen television. In order to preserve the aspect ratio of the original video content, the picture is scaled down so that it fits the available width of the television screen. Since the picture will not fill the screen vertically, dark bars are drawn in above and below the picture.
Liquid Crystal Display — An LCD television or monitor uses liquid crystals that act as "shutters" within the television screen. An LCD television has thousands of small light sources at the rear of the display. A layer of cells containing the liquid crystals is placed between the light sources and the display screen. When the liquid crystal cells are electrified with current, the crystals align and block any light from shining through, or scatter allowing the light to shine through to the screen. LCD monitors typically only display video signals in a progressive scan format. LCD monitors do not use phosphors and are not susceptible to screen burn.
Pillarbox Mode — A method of presenting standard screen images on a widescreen television. In order to preserve the aspect ratio of the original content, the picture is scaled so that it fits the available height of the television screen. Since the picture will not fill the screen horizontally, dark bars are drawn in to the left and right of the picture. Pillarbox presentation is also referred to as "Curtained" or "Sidebarred" modes.
Pixel — The term "pixel" comes from the phrase "picture element" and is equivalent to a dot on a screen. High-Definition pictures are comprised of many more horizontal and vertical colored dots than standard definition pictures. In the DTV world, pixels are broadcast as either square-shaped or rectangular-shaped pieces of the total picture.
Plasma Display — A plasma television uses hundreds of thousands of tiny cells embedded in the screen to produce a picture. Each cell represents a pixel, and each cell is comprised of three subcells. The three subcells are filled with plasma gas that glows either red, blue, or green (depending on the phosphor coating) whenever it is electrically excited. The colored light emitted by the three RGB subcells combine to form a single colored pixel on the screen. Since plasma displays use phosphor, they are susceptible to screen burn.
Postage Stamp — A term used to describe the scenario in which a picture displayed on a television screen is framed on all four sides by black bars. The picture appears to be letterboxed and pillar boxed simultaneously, resulting in a very small picture being displayed in the center of the television screen. A postage stamp display can occur in certain conditions when video is converted from one format and aspect ratio to another.
Progressive Scan — A method of drawing a picture frame on a television screen in its entirety without drawing two separate fields. The picture is drawn from left to right and top to bottom in one scan without skipping any lines. This method reduces the flicker of the picture on the television screen and results in smoother motion on the screen.
Projection Display — A projection television uses an internal video projector (either LCD or CRT) to create a small version of the picture image, which is then magnified and projected onto a large viewing screen. Projection displays are used to create very large screens, but their sharpness and clarity can be very adversely affected by the viewer's position relative to the screen. Since the video source inside a projection television uses phosphors, the video source itself is susceptible to screen burn.
Resolution — The measure of a television picture's sharpness and clarity related to the amount of picture information in the signal. DTV resolution is typically measured in terms of horizontal and vertical pixels.
Screen Burn — Screen burn is a condition that can arise when significant portions of a television screen are not used to display active video for prolonged durations of time. This can occur when 4:3 pictures are constantly presented on a 16:9 television screen, or 16:9 pictures are constantly presented on a 4:3 television screen. The pixels in the dark sidebars are not exercised and wear much less rapidly, so that when the full display is finally utilized, there are noticeable differences in the brightness and clarity of the unexercised pixels. In addition, bright images that remain stationary on any screen that uses phosphor technology to generate the image can become burned into the screen, resulting in an annoying "ghost image" that remains permanently on the screen.
SDTV — DTV signals that feature vertical and horizontal resolutions comparable to current NTSC analog television signals, typically using a standard 4:3 aspect ratio. SD programs are drawn using interlaced scan methods. For the most part, all HDTV monitors are capable of supporting an interlaced SDTV (480i) signal, some also support 480P.
Upscaling — A process by which a program is converted to a higher resolution than its native format. The process may also involve a conversion between progressive and interlaced scan formats. Upscaled content can look fuzzy or distorted compared to its native resolution.
Widescreen — Widescreen is a term equally applied to both television sets and video programs. A widescreen television has a picture screen that is roughly 1.78 times wider than it is high. Widescreen video programs can vary in their aspect ratio, but the pictures are typically at least 1.5 times wider than they are high. Motion pictures shown at the theater may feature video that is 2.35 times wider than it is high. Often referred to as "Panavision" and "CinemaScope."
YPbPr — YPbPr represents component video connections, where luminance (Y) is represented by a green jack, separate from the color components blue (Pb) and red (Pr). Most high-definition sets today support this format. These colors should not be confused as RGB output.
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