Glossary of Video Terms and Acronyms - Isotest

Video Terms and Acronyms
Glossary
D
D – Definition.
D1 – A non-compressed component digital video recording format that
uses data conforming to the ITU-R BT.601-2 standard. Records on highend
19 mm (3/4") magnetic tape recorders. Systems manufactured by
Sony and BTS. Most models can record 525, 625, ITU-R BT.601-2, and
SMPTE 125M. The D1 designation is often used incorrectly to indicate
component digital video.
D16 – A format to store film resolution images on D1 format tape
recorders. Records one film frame in the space normally used for 16 video
frames.
D2 – A non-compressed composite digital video recording format originally
developed by Ampex that uses data conforming to SMPTE 244M and four
20-bit audio channels. Records on high-end 19 mm (3/4") magnetic tape
recorders. It uses the same tape cassette cartridge but the tape itself is
metal particle tape like Beta SP and MII. The D2 designation is often used
incorrectly to indicate composite digital video.
D2-MAC – Similar to D-MAC, the form preferred by manufacturers for
European DBS. See also MAC.
D3 – A non-compressed composite digital video recording format that uses
data conforming to SMPTE 244M and four 20-bit audio channels. Records
on high-end 1/2" magnetic tape similar to M-II. The format was developed
by Matsushita and Panasonic.
D4 – A format designation never used due to the fact that the number four
is considered unlucky (being synonymous with death) in some Asian languages.
D5 – A non-compressed, 10-bit 270 Mbit/second, component or composite
digital video recording format developed by Matsushita and Panasonic. It is
compatible with 360 Mbit/second systems. It records on high-end 1/2"
magnetic tape recorders.
D6 – A digital tape format which uses a 19 mm helical-scan cassette tape
to record uncompressed high definition television material at 1.88 GBps
(1.2 Gbps).
D7 – DVCPRO. Panasonic’s development of native DV component format.
D8 – There is no D8, nor will there be. The Television Recording and
Reproduction Technology Committee of SMPTE decided to skip D8 because
of the possibility of confusion with similarly named digital audio and data
recorders.
D9 – Digital-S. A 1/2-inch digital tape format developed by JVC which
uses a high-density metal particle tape running at 57.8 mm/s to record a
video data rate of 50 Mbps.
DA-88 – A Tascam-brand eight-track digital audio tape machine using the
8 mm video format of Sony. It has become the defacto standard for audio
post production though there are numerous other formats, ranging from
swappable hard drives to analog tape formats and everything in between.
DAB – See Digital Audio Broadcasting.
DAC – Digital-to-Analog Converter.
44 www.tektronix.com/video_audio
DAC to DAC Skew – The difference in a full scale transition between R, B,
and B DAC outputs measured at the 50% transition point. Skew is measured
in tenths of nanoseconds.
Daisy Chain – Bus line that is interconnected with units so that the signal
passes from one unit to the next in serial fashion.
DAM – DECT Authentication Module.
Damped Oscillation – Oscillation which, because the driving force has
been removed, gradually dies out, each swing being smaller than the preceding
in smooth regular decay.
DAT (Digital Audio Tape) – a) A consumer digital audio recording and
playback system developed by Sony, with a signal quality capability surpassing
that of the CD. b) A magnetic tape from which you can read and to
which you can copy audio and digital information.
Data – General term denoting any or all facts, numbers, letters, and symbols
or facts that refer to or describe an object, idea, condition, situation,
or other factors. Connotes basic elements of information that can be
processed or produced by a computer. Sometimes data is considered to be
expressible only in numerical form, but information is not so limited.
Data Acquisition – Collection of data from external sensors usually in
analog form.
Data Base – Systematic organization of data files for easy access,
retrieval, and updating.
Data Bus – Set of lines carrying data. The data bus is usually bidirectional
and three-state.
Data Carousels – The data broadcast specification for data carousels
supports data broadcast services that require the periodic transmission of
data modules through DVB compliant broadcast networks. The modules are
of known sizes and may be updated, added to, or removed from the data
carousel in time. Modules can be clustered into a group of modules if
required by the service. Likewise, groups can in turn be clustered into
SuperGroups. Data broadcast according to the data carousel specification
is transmitted in a DSM-CC data carousel which is defined in MPEG-2
DSM-CC. This specification defines additional structures and descriptors to
be used in DV compliant networks. The method is such that no explicit references
are made to PIDs and timing parameters enabling preparation of
the content off-line.
Data Compression – Application of an algorithm to reduce the bit rate of
a digital signal, or the bandwidth of an analog signal while preserving as
much as possible of the information usually with the objective of meeting
the constraints in subsequent portions of the system.
Data Domain – Analysis or display of signals in which only their digital
value is considered and not their precise voltage or timing. A logic state
analyzer displays information in the data domain.
Data Element – An item of data as represented before encoding and after
decoding.