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Glossary
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Glossary
Clip
A recording unit. Clips are created
every time recording starts and stops.
Clip list
A list of locations in the material
recorded on the disc, arranged in any
order. Clip lists can be created with
the scene selection function of this
unit, and with the supplied PDZ-1
Proxy Browsing Software.
Composite video signal
A video signal in which luminance
and chrominance are combined along
with timing reference “sync”
information to make composite
video.
Drop-frame mode
SMPTE time code runs at 30 frames/
second, while the NTSC color
television system runs at about 29.97
frames/second. Drop-frame mode
adjusts the running of time code to
eliminate the discrepancy between
time code value and actual time by
dropping two frames from the time
code value at the beginning of each
minute except every tenth minute.
Essence mark
A type of metadata that may be set for
a specified frame.
For more efficient searches,
XDCAM equipment records essence
marks as part of Non-RealTime
metadata, and uses them to display
thumbnails.
i.LINK
Another name for the IEEE1394-
1995 standards and their revisions.
XDCAM uses the i.LINK interface to
transfer DV streams by the AV/C
protocol, and to read and write
MPEG HD and DVCAM data files
by FAM (file access mode).
Metadata
Information about the properties of
video and audio content. XDCAM
records metadata such as UMIDs and
essence marks, and the supplied
PDZ-1 Proxy Browsing Software can
be used to record information such as
titles and comments.
MXF
Material eXchange Format. A file
exchange format developed by the
Pro-MPEG Forum. Equipment from
different manufacturers can
exchange files in this format.
Non-drop-frame mode
A mode of advancing time code
which ignores the difference in frame
values between real time and the time
code. Using this mode produces a
difference of approximately 86
seconds per day between real time
and time code, which causes
problems when editing programs in
units of seconds using the number of
frames as a reference.
Proxy AV data
Low-resolution data with a video
bandwidth of 1.5 Mbps and an audio
bandwidth of 64 kbps per channel.
This unit records proxy AV data
automatically whenever high-
resolution MPEG HD or DVCAM
data is recorded.
S/N
Signal-to-Noise ratio. The relation of
the strength of the desired signal to
the accompanying electronic
interference, the noise. If S/N is high,
sounds are reproduced with less noise
and pictures are reproduced clearly
without snow.
Sub clip
One of the sections which make up a
clip list. A sub clip may be part of a
clip or an entire clip.
Thumbnail image
A reduced still picture of video for
display on a GUI screen. XDCAM
creates thumbnail images from proxy
video, and displays them as index
pictures on GUI screens.
Time code
A digitally encoded signal which is
recorded with video data to identify
each frame of the video by hour,
minute, second and frame number.
SMPTE time code is applied to
NTSC system, and EBU time code to
PAL and SECAM systems.
UMID
Unique Material Identifier. A
standard (SMPTE 330M) for video
and audio metadata. The Basic
section of a UMID contains a
globally unique number and a
material number for the identification
of recorded material. An optional
section called the “Source Pack”
contains information such as the time
and location of recording. A UMID
with the Basic section only is called a
Basic UMID. A UMID with the
Source Pack is called an Extended
UMID.
User bits
A total of 32 bits are provided in the
time code which the user can use to
record such information as date, reel
number, or scene number on video
tape or disc. Also called user’s bits.
VBID (Video Blanking ID)
This is a video ID signal, defined in
the EIAJ CPR-1204 standard, which
is inserted into VBS video output to
enable the aspect ratio to be detected.
The ID signal is inserted into line 20,
VBI 283.
