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Graphics and Video
Definitions ACTIVE MATRIX: Active Matrix is a technology used
in the flat panel liquid crystal displays of notebook and laptop computers.
The term Matrix applies to the "grid" of liquid crystal elements
that make up each pixel on the screen. Images displayed on active matrix
screens are more responsive than previous LCD screen technologies. Also, this
type of display can be seen more clearly at a wider viewing angle than
earlier screen types such as DSTN
displays. Active Matrix displays are also known as TFT
displays. AGP: Accelerated Graphics Port.
Is a modern video technology that is geared towards the high speed display of
3-D graphic images. AGP graphics cards have replaced PCI graphics cards in
IBM compatible personal computers. BITMAP: A bitmap or "bit map" is
a "map" (a description) of the bits (pixels) of a graphic image,
usually a rectangular area. Many types of bitmap files exist, each being
formatted in a way that allows for more or less video information to be
stored for each image. Some bitmap file formats are better at
compressing video information than others. Some are able to store more color
information or other types of video information (transparency, opacity, etc.)
Common bitmap file formats include GIF, JPG, and BMP. BMP: BMP is a specific type of
graphics file and derives its name from the term "bitmap". All BMP
files are bitmap files but not all bitmap files are BMP files. GIF and JPEG
are bitmap files but they store information about graphic images (bitmaps) in
a different (and more efficient) format than BMP files. The Microsoft
"Paint" application program creates files in BMP format. CGA: Color Graphics Adapter.
Predecessor to EGA. A type of display technology developed by IBM around
1981. This technology was capable of displaying four colors, and had a
maximum resolution of 200 by 320 pixles. This resolution was not very good
and was soon replaced by EGA display technology. This technology was used by
the early IBM PCs and IBM XTs and compatibles. CRT: Cathode Ray Tube. This
is an age-old term for a computer monitor. The term "cathode ray
tube" applies to the technology used in the construction of the picture
tube portion of a monitor. There is an electronic component called a
"cathode" (a.k.a. electron "gun") that emits a beam (or
"ray") of electrons in the direction of the front of the monitor
(the screen) so that you can see images on your monitor. DISPLAY ADAPTER: This is another name for a video controller card, the circuit card and
supporting computer chips needed to control the display of information on a
computer screen (i.e. display). DOT PITCH: Dot Pitch is a measure of the
resolution/sharpness of a computer display. A "dot" is the smallest
physical element of a monitor that lights up to form part of an image on your
screen. Dot pitch is measured in millimeters (mm) and it is the distance
between two adjacent "dots" on the screen. The smaller the
"dot pitch" the higher the resolution of the display. High quality
modern SVGA displays are in the range of .25 to .26mm. .28 is average quality
and anything in the range of .30 or higher is not very high quality (does not
display a very sharp image) for computer monitors. However, a very large
monitor that is meant to be viewed at a distance, such as at a train
terminal, need not have a small dot pitch. DPI: Dots Per Inch. This is the measure of the resolution of
devices such as printers and scanners. High resolution printers are in the
range of 600 to 1200 DPI and high resolution scanners are in the range of
9600 DPI. DSTN: A particular type of video display
technology for laptop, portable and handheld devices. Short for Double Layer
Supertwist Nematic, a passive-matrix LCD technology that uses two display layers to counteract the color
shifting that occurs with conventional supertwist displays. DVD: Digital Versatile Disk. This is a
modern type of optical disk technology that is replacing CD-ROM technology. A
DVD disk has a capacity of 4.7 GB (or 4,700 MB) as compared to a CD-ROM which
has a capacity of 650 MB. This capacity is sufficient for storing over 2
hours of high resolution video. DVD disks commonly use the MPEG compression
format. DVD DECODER: A DVD decoder is a circuit card
that utilized a processor chip to decode/decompress video information stored
on a DVD disk. Software is also available to decode DVD information using
only the CPU of your PC rather than relying on a separate DVD circuit card. EGA: Enhanced Graphics Adapter. Predecessor to VGA. EGA
display technology wasa developed by IBM around 1984. It was capable of
displaying up to 16 different colors. It had a screen resolution of 350 by
640 pixels allowing for much higher quality graphics and text than the CGA
technology it replaced. This technology was used by the later IBM PCs
including the 286 "AT" PCs. GIF: Graphics Interchange Format.
A GIF file is a file containing graphical information encoded in the GIF
format. GIF is one of the most common encoding/compression formats.
Unlike the JPG format, the GIF format does not lose any of the quality of the
original image. HDTV: High Definition TeleVision.
HDTV is a technology that supports much higher quality video and audio than
conventional television. HDTV signals are usually digitally encoded (int
MPEG-2 format) as compared to the analog format of conventional TV. JPEG: Joint Photographic Experts
Group. This organization defined the specifications for the JPG
graphics file format. This is a video file format that allows you to specify
the degree of compression which in turn dictates the image
quality/resolution. The higher the compression, the lower the resolution of
the stored image and vice versa. LCD: Liquid Crystal Display.
LCD screens are the flat-panel screens used in laptop and notebook computers.
They have been developed using various tecnologies such as DSTN
(passive matrix) and TFT (active matrix). Monochrome: Single color monitor (i.e. black and white screen or amber screen or
green screen) MPEG: Moving Picture Experts
Group. This organization develops standards compressing digital audio
and digital video information. They have developed several standards so far
including MPEG-1, MPEG-2, and MPEG-3. PASSIVE MATRIX: This is a flat panel (flat screen)
technology that preceded the active matrix technology. PIXEL: A word derived from the words
"picture element". A pixel could be the same as an actual
(physical) phosphor "dot" on your computer screen. In fact, that is
often the way the word pixel is used. However from a programming (i.e.
logical) point of view, a pixel could also be a group of adjacent physical
dots on your screen, depending on what the resolution setting for your
monitor/display within your operating system. In that case, a "low"
resolution setting would result in larger text on the screen and a larger
"logical" pixel size and a "high" resolution setting
would result in smaller text on the screen and a smaller "logical"
pixel size. PNG: Portable Network Graphics.
This is a graphics file format like GIF and JPEG for storing image files in
compressed format. PNG is most like the GIF format in that there is no loss
of image information after a file is decompressed. This file format
will probably replace the GIF format since it has features that the GIF
format does not have including the ability to control the video
characteristics such as image opacity and brightness. PPI: Pixels Per Inch. A unit of measurement
of screen resolution where a pixel is equivalent to the smallest
displayable/viewable dot on a computer display. From the point of view of
computer programs that send output to the screen, a pixel can also be mapped
to several actual physical "dots" on the screen. RGB: Red, Green, and Blue.
RGB displays typically have at least 3 input jacks for red, green and blue
signal wires from the computer's display adapter card. The red, green, and
blue signals can be combined in various intensities to obtain any of up to
16,777,216 possible colors (256 times 256 times 256 levels of intensity for
each color). SVGA: Super Video Graphics Array
or simply Super VGA. This is the type of display (video monitor) most
commonly used today. SVGA resolution is primarily dependend on the amount of
video memory (video RAM) on your dipslay adapter card and the size of the
display (computer screen). A SVGA monitory can display up to 16,000,000 with
a resolution of up to 600 by 800 for 14 inch monitors anda a resolution of up
to 1200 by 1600 pixels for 20 inch monitors. TFT: Thin Film Transistor. A type of
technology used to construct Active Matrix
displays, commonly used with laptop computers. VGA: Video Graphics Array.
Predecessor to SVGA. VGA is a type of display technology developed by IBM
around 1987. The maximum resolution for VGA displays varies from 16
colors at 640 x 480 pixels to 256 colors at 320 x 200 pixels. This technology
came into wide use with the advent of Intel 386 PCs. XGA: Extended Graphics Array.
This display technology was developed by IBM around 1990. It replaced the
8514 display technology. Please visit Bob Johnson's Computer Stuff! We sell quality new and used computer hardware. If you need a specific product we can find it for you!!! Just call us toll free at 1-877-202-7788!!! |
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