MOTU micro express-USB, Руководство пользователя

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APPENDIX
141
A
Glossary
Address Track:
A third audio track, used for time
code, located on the edge of the video signal on a 3/
4” VTR. Because of its proximity to the video
signal, the address track cannot be recorded by
itself; it must be recorded simultaneously with the
video signal.
ATR:
Audio Tape Recorder . A device that can record
an audio signal on audio tape.
Base setup: One of eight MIDI Timepiece AV
internal basic configurations. Each base setup
stores all of the MIDI Timepiece AV internal
settings as one configuration. Each base setup can
be configured differently from the others.
Burn-in Window:
A numeric display of time code
superimposed over the video picture to aid in the
post-production editing process.
Cable routing:
An internal connection from one of
the MIDI Timepiece AV’s MIDI IN ports to one or
more of its MIDI OUT ports.
Control Track:
A video tape track located at the
edge of the video tape containing a series of pulses
that serve as a reference tracking the tape speed.
This track is recorded with the video signal.
CRT:
Cathode Ray Tube . The glass screen in TV’s,
computers, etc. upon which video images are
projected.
Crosstalk: Interference on a track from the signal
of an adjacent track on a multitrack tape recorder.
Default:
An initial value or configuration.
Drop Frame:
A SMPTE time code format used to
compensate for an accumulating timing error in
color video. Drop Frame skips two frames at the
beginning of each minute (except every 10th
minute) as it counts color video frames. The result
is that the SMPTE time code values match the
actual elapsed time, since color video runs slower
(29.97 frames per second) than black and white
video (30 frames per second). Drop-frame is
required only with color video programs in which
the SMPTE time code numbers must precisely
match the actual elapsed time.
Drop-out:
A brief period of missing information in
a continuous signal, such as a video signal or
SMPTE time code signal. Drop-outs are usually
caused by small, physical imperfections in the
surface of the tape on which the signal is recorded.
Flywheeling:
Another name for Freewheeling . See
Freewheeling below.
Freewheeling: A process in which a synchronizer,
such as the MIDI Timepiece AV, continues to
generate time code even when it encounters drop-
outs in a time code source. Converters may briefly
lose synchronization during a drop-out and, in
turn, momentarily stop converting time code. The
MIDI Timepiece AV can freewheel up to 32 frames,
making it insusceptible to drop-outs.
FSK:
Frequency Shift Key . An audio time code
consisting of a series of pulses which increment the
counter of an FSK reading device.
Genlock: A process in which a video generator
(graphics, picture, or VITC) is locked in phase with
an external source.
!USB Interfaces Manual Book Page 141 Tuesday, October 10, 2000 12:43 PM