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.
Chroma Key Background
Background elements are those pixels in the source video
that are the same color as the one you chose to key out.
Note that the Shadow and translucent areas (see below)
are completely contained within the Background area.
Chroma Key Edge Softness
Edge Softness lets you apply varying degrees of softening
to the Foreground edges to help it blend in with the
underlying background image that it is being keyed over.
Chroma Key Foreground
Foreground elements are those pixels that are not within
the Background, Shadow, Translucency, or Transition
ranges. This is the area with colors that will not be keyed
out and will remain solid.
Chroma Key Luminance
Luminance allows you to control the overall brightness
of Shadow, Translucency, and Transition areas as well
as partial reflections to more closely match the
Foreground brightness.
Chroma Key Shadow
Shadow elements are those pixels in the source video
with colors that are within the Background range, but
with lower luminance values, depending on the shadow
range. You modify the Shadow range to cover darker
areas of the background (e.g. where the foreground is
casting a shadow on the background screen).
Chroma Key Spill Suppress
Spill Suppression elements are those pixels in the
Foreground that have a noticeable tint of the Background
color. This typically occurs around the edge of the
foreground subject as glow from the background
blue-screen or green-screen “spills” onto them.
Chroma Key Translucency
Translucent elements are those pixels in the source video
that are in the Background range, but with higher
luminance values than the Shadow range. You can control
the upper-end of the Translucency range by setting a
wider hue-range to constrain the area. You can also
control the transparency of the Translucent area.
Chroma Key Transition
Transition elements are those pixels in the source video
with colors that are not within any of the previous three
ranges and are also not considered part of the Foreground
area. These are typically the pixels near the edge of the
foreground, where it blends into the background.
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.
Acuity Setup Manual (v9.2) — Glossary •
115
Содержание Acuity 4410AR-020
Страница 1: ...Acuity Setup Manual v9 2...
