Glossary
Interlaced
An Interlaced video format starts at the top of the screen
and draws all the odd number scan lines and then all the
even number scan lines in sequence. This results in half
the image being drawn in one pass and the other half of
the image being drawn in the second. These two passes
are called Fields, where the first pass is called Field 1
and the second pass is called Field 2. When both Field
1 and Field 2 have been drawn, resulting in a complete
image, you have a single Frame.
Progressive
A Progressive scan video format draws each scan line in
sequence, starting from the top of the screen and working
to the bottom. Unlike Interlaced, with Progressive scan
the entire image is drawn at one time, in a single pass.
This means that there are no fields in a Progressive scan
image.
Auto Key
A pairing of two video signals, a key video and a key
alpha, to create a key. In the switcher, you associate the
fill and alpha so that the switcher knows which alpha to
use when the video is selected.
Auto Transition
An automatic transition in which the manual movement
of the fader handle is simulated electronically. The
transition starts when the
AUTO TRANS
button is
pressed and takes place over a pre-selected time period,
measured in frames.
Chroma Key
Chroma Key is a key in which the hole is cut based on
a color value, or hue, rather than a luminance value or
alpha signal. The color is removed and replaced with
background video from another source.
Cut
An instantaneous switch from one video signal to another.
Dissolve
A transition from one video signal to another in which
one signal is faded down, while the other is
simultaneously faded up. The terms mix or cross-fade
are often used interchangeably with dissolve.
Dynamic Host Configuration Protocol
An Ethernet protocol where a device, such as the
switcher, is given an IP address by the network host. This
eliminates the need to manually enter the network
parameters and IP address.
Field
One half of a complete picture (or frame) interval
containing all of the odd, or all of the even, lines in
interlaced scanning. One scan of a TV screen is called a
field; two fields are required to make a complete picture
(which is a frame).
Force, Mask
An effect that forces the masked region to the foreground
but is not bound by the key. For example, if you have a
key and apply a mask to it. The masked area is bound by
the edges of the key. When force is turned on, the masked
area is filled with the video from the key (nothing appears
masked) but you can move the mask outside of the key
and the key video is still filling the masked region.
Frame
One complete picture consisting of two fields of
interlaced scanning lines.
File Transfer Protocol
A network protocol that is used to transfer files from one
host computer to another over a TCP-based network.
Gain
Gain represents the range of signal values present in a
video signal from a lowest to a highest point (from black
to white for example). Increasing gain expands this range,
while decreasing gain compresses this range. Clipping
occurs if applied gain changes cause output signal values
to fall outside the allowable range. Generally, increasing
the gain for a specific color component causes the video
signal colors to become increasingly saturated with that
color. Similarly, decreasing the gain for a specific color
component progressively removes that color component
from the output video signal.
Gamma
Gamma corrections introduce non-linear corrections to
a video signal. A gamma correction can be described as
taking a point on the output versus input video signal
line and pulling it perpendicularly away from the line.
The result is a Bezier curve between the start, the new
point, and the end point. Generally, increasing the gamma
value adds more of the component to the video signal in
the location of the gamma offset point. Decreasing the
gamma value reduces the amount of the component in
the video signal in the location of the gamma offset point.
Moving the gamma offset point allows you to select
which part of the input video signal receives the gamma
Carbonite Operation Manual (v13.0) — Glossary •
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