RAM installed on a video adapter. Before an image can be sent to a display monitor, it is first represented as a bit map in an area of video memory called the frame buffer. The amount of video memory, therefore, dictates the maximum resolution and color depth available.
With a conventional video adapter, the bit map to be displayed is first generated by the computer’s microprocessor and then sent to the frame buffer. Most modern video adapters, however, are actually graphics accelerators. This means that they have their own microprocessor that is capable of manipulating bit maps and graphics objects. A small amount of memory is reserved for these operations as well.
Because of the demands of video systems, video memory needs to be faster than main memory. For this reason, most video memory is dual-ported, which means that one set of data can be transferred between video memory and the video processor at the same time that another set of data is being transferred to the monitor. There are many different types of video memory, including VRAM, WRAM, RDRAM, and SGRAM.
- video mode
The setting of a video adapter. Most video adapters can run in either text mode or graphics mode. In text mode, a monitor can display only ASCII characters. In graphics mode, a monitor can display any bit-mapped image. In addition to the text and graphics modes, video adapters offer different modes of resolution and color […]
- video overlay
The placement of a full-motion video window on the display screen. There are various techniques used to display video on a computer’s screen, depending on whether the video source has been digitized or is still in analog NTSC format. Since computer monitors are generally analog, NTSC video can be merged with signals coming from the […]
- video standards
There are a variety of video standards that define the resolution and colors for displays. Support for a graphics standard is determined both by the monitor and by the video adapter. The monitor must be able to show the resolution and colors defined by the standard, and the video adapter must be capable of transmitting […]
- video switcher
Also called a vision mixer, a video switcher is a hardware device used in video and film production to switch between different video or audio sources. This allows the producer to mix video and also add in special effects or footage captured on a secondary source.
- video transition
In video editing a transition is what the author shows between two shots or clips. The joining of those clips is the transition from one to the other. Transitions can be an instant scene or image change, a fade, fade to black, dissolve, pan from one person to another, or any digital effect.