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| Multimedia is a term typically used to mean the | combination of text, sound, and motion video. |
| key components that may be included in a multimedia system | microphone, connection to the Internet, Digital still pictures and video cameras, A video capture card, MPEG hardware and web-based movie players |
| A video adapter (also called a display adapter or video board) is an | integrated circuit card in a computer that provides digital-to-analog conversion, video RAM, and a video controller so that data can be sent to a computer display. |
| almost all displays and video adapters adhere to the standard | Video Graphics Array (VGA). |
| VGA is how data is passed between the | computer and the display |
| VGA is responsible for the frame refresh rates in hertz and the | number and width of horizontal lines, which essentially amount to specifying the resolution of the pixels that are created. |
| Video Electronics Standards Association (VESA) | defines how software can determine the capability of a display |
| Video Electronics Standards Association (VESA) identifies resolutions setting | beyond those of VGA. |
| A display is a computer output surface and projecting mechanism that shows | text and often graphic images, using a Cathode Ray Tube (CRT), Liquid Crystal Display (LCD), light-emitting diode, gas plasma, or other image projection technology. |
| Displays (and monitors) are sometimes called | Video Display Terminals (VDT) or Video Display Units (VDU). |
| Most computer monitors use | analog signals to display the image. |
| The video adapter takes the digital data sent by application programs, stores it in | video Random Access Memory (video RAM), and converts it to analog data for the display scanning mechanism using a Digital-to-Analog Converter (DAC). |
| Computer video displays can be characterized according to | Color capability, Sharpness and viewability, The size of the screen, The projection technology |
| video displays can usually operate in one of several display modes that determine | how many bits are used to describe color and how many colors can be displayed. |
| bit depth 1 | number of colors: 2 (monochrome) |
| bit depth 2 | number of colors: 4 (CGA) |
| bit depth 4 | number of colors: 16 (EGA) |
| bit depth 8 | number of colors: 256 (VGA) |
| bit depth 16 | number of colors: 65,536 (High Color, XGA) |
| bit depth 24 | number of colors: 16,777,216 (Ture Color SVGA) |
| bit depth 32 | number of colors: 16,777,216 (True Color Alpha Channel) |
| The absolute physical limitation on the potential image sharpness of a | screen image is the dot pitch. |
| Dot pitch is a diagonal distance between the | same color phosphor dots. |
| The smaller the dot pitch, the | greater the potential image sharpness. |
| The dots-per-inch is determined by a combination of the screen | resolution (that is, how many pixels are projected on the screen horizontally and vertically) and the physical screen size. |
| Viewability | the ability to see the screen image from different angles. |
| On desktop computers, the display screen width relative to height, known as the | aspect ratio, is generally standardized at 4 to 3 |
| Screen sizes are measured in | either millimeters or inches diagonally from one corner to the opposite corner. |
| LED and gas plasma work by lighting up | display screen positions based on the voltages at different grid intersections. |
| LCDs work by | blocking light rather than creating it. |
| Displays generally handle data input as | character maps or bitmaps. |
| In character-mapping mode, a display has a | pre-allocated amount of pixel space for each character. |
| In bitmap mode, the display receives an exact representation of the screen image that is to be projected in the form of | a sequence of bits that describe the color values for specific X and Y coordinates starting from a given location on the screen. |
