Matrox Meteor-II Installation And Hardware Reference Manual page 62

62 Appendix D: Glossary
• Reference levels
The zero and full-scale levels of an analog-to-digital converter. Voltages below a
black reference level are converted to a zero pixel value; voltages above a white
reference level are converted to the maximum pixel value. Together with the analog
gain factor, the reference levels affect the brightness and contrast of the resulting
image.
• RGB
A color space that represents color using the primary colors (red, green and blue)
as components.
• Synchronous function
A function that does not return control to the caller until it has finished executing.
See also asynchronous function.
• Vertical sync
The part of a video signal that indicates the end of a frame and the start of a new
one.
See also horizontal sync.
• VIA
Video Interface ASIC. A custom ASIC that connects all the data buses on the board
(grab and PCI bus) to one another, and directs and monitors data flow "traffic".
It is a video interface that provides various ways of inputting and outputting data.