Apple Final Cut Pro 7 - Manual (Page 193)

Many PCI Express cards aren’t big enough to fit all of the necessary video and audio
connectors. In these situations, a breakout box is connected to the PCI Express card via
a multipin connector on a long cable, and the connectors are accessible on the breakout
box instead of the back of the PCI Express card. A breakout box is also useful because it
allows you to place the connectors somewhere more convenient than the back of your
computer, such as an equipment rack or a desktop.
Analog or digital VTR Computer
(with PCI card)
Breakout box
BNC connector
USB Video Interface
USB video interfaces cannot support the high data rates required for professional video
use, so they are not commonly used. USB video interfaces are usually used for converting
analog video sources to a digital signal for capture.
USB interface
USB RCA connector
Analog VTR Computer
Video Signals and Connectors
When you capture and output, the type of video signal you use to connect your equipment
is a critical factor that goes into determining the quality of your video. Video camcorders,
decks, and monitors can use different types of signals, depending on the environment
they are intended for. Consumer equipment usually has limited video signal choices;
professional equipment gives you the greatest range of options.
For more information, see “Video Formats.”
Composite
Composite is the lowest common denominator of video signals. A composite signal runs
all color and brightness information on a single cable, resulting in lower-quality video
compared to the quality of other formats. Nearly all video devices have a composite input
and output. This format uses a single RCA or BNC connector.
193 Chapter 12 Connecting Professional Video and Audio Equipment