Glossary of Video Terms and Acronyms - Isotest

Video Terms and Acronyms
Glossary
CCETT (Centre Commun d’Etudes de Telecommunications et de
Telediffusion, France) – The CCETT is one of the three licensors of the
MPEG Layer II coding algorithm. The audio coding technique, originally
developed for DAB under EUREKA 147 jointly with IRT and Philips, was
selected by ISO/MPEG as Layer II of the MPEG-1 standard.
CCIR (Comite Consultatif Internationale des Radiocommunications) –
International Radio Consultative Committee, an international standards
committee that has been absorbed by the parent body, the ITU. A permanent
organization within the ITU with the duty to study technical and operating
questions relating specifically to radio communications and to make
recommendations on them. The CCIR does not prepare regulations; it
draws up recommendations and reports, produced by experts from both
public and private entities, which provide guidance on the best operational
methods and techniques. The CCIR is expected to base its recommendations
upon 150 and IEC international standards, but when no relevant one
exists, the CCIR has been known to initiate standardization. These recommendations
and reports provide a basis for international standardization of
telecommunications.
CCIR-468 – Specifies the standard for weighted and unweighted noise
measurements. The weighted standard specifies the weighting filter and
quasi-peak detector. The unweighted standard specifies a 22 Hz to 22 kHz
bandwidth limiting filter and RMS detector.
CCIR-500 – Method for the Subjective Assessment of the Quality of
Television Pictures. CCIR-500 is a detailed review of the recommendations
for conducting subjective analysis of image quality. The problems of defining
perceived image quality are reviewed, and the evaluation procedures
for interval scaling, ordinal scaling, and ratio scaling are described – along
with the applications for which each is best employed.
CCIR-601 – See ITU-R BT.601.
CCIR-656 – The physical parallel and serial interconnect scheme for ITU-R
BT.601-2-601. CCIR 656 defines the parallel connector pinouts as well as
the blanking, sync, and multiplexing schemes used in both parallel and
serial interfaces. Reflects definitions in EBU Tech 3267 (for 625 line signals)
and in SMPTE 125M (parallel 525) and SMPTE 259M (serial 525).
CCIR-6601 – Consultative Committee International Radio. A standard that
corresponds to the 4:2:2 format.
CCIR-709 – The recommendation considers that the HDTV studio standard
must be harmonized with those of current and developing television systems
and with those of existing motion-picture film. In a review of current
systems, a consensus was identified in specifications for opto/electronic
conversion, picture characteristics, picture scanning characteristics, and
signal format (both analog and digital representations). Work is underway in
the editing of national and CCIR-related documents to determine whether
these consensus values may be affirmed in the next review of the individual
documents. The values in Rec 709 are considered interim, and CCIR
notes that continuing work is expected to define target parameters for
future improved image rendition.
CCIR-801 – At present, the first results on studies related to Study
Programme 18U/11 have been collected. It must be recognized that these
studies must be intensified in close cooperation with such organizations as
the IEC and ISO to take fully into account the requirements for implementa-
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tion of HDTV for media other than broadcasting, i.e., cinema, printing,
medical applications, scientific work, and video conferencing. In addition,
the transmission of HDTV signals via new digital transmission channels or
networks has to be considered and taken into account.
CCITT (Comite Consultatif Internationale Telegraphique et
Telephonique) – A committee of the International Telecommunications
Union responsible for making technical recommendations about telephone
and data communication systems for PTTs and suppliers. Plenary sessions
are held every four years to adopt new standards.
CCITT 0.33 – Recommendation 0.33 of the CCITT Specification for
Measuring Equipment, Volume IV, Series O Recommendations-1988. This
defines the automatic test sequences that are used to check on the different
parameters that are important to signal quality. Recommendation 0.33
has defined sequences for both monaural and stereo audio testing. Also
called EBU Recommendation R27.
CCK – See Composite Chroma Key.
CCTV – See Closed Circuit TV.
CCU – See Camera Control Unit.
CD – Committee Draft.
CD (Compact Disc) – A 4.75" disc used to store optical, machinereadable,
digital data that can be accessed with a laser-based reader such
as a CD player.
CD-DA (Compact Disc-Digital Audio) – Standard music CDs. CD-DA
became CD-ROMs when people realized that you could store 650 Mb of
computer data on a 12-cm optical disc. CD-ROM drives are simply another
kind of digital storage media for computers, albeit read-only. They are
peripherals just like hard disks and floppy drives. (Incidentally, the convention
is that when referring to magnetic media, it is spelled disk. Optical
media like CDs, laserdisc, and all the other formats are spelled disc.)
CDDI (Copper Data Distributed Interface) – A high-speed data interface,
like FDDI but using copper. See FDDI.
CD-I – See Compact Disc Interactive.
CD-ROM – See Compact Disc Read Only Memory.
CDTV – See Conventional Definition Television.
CD-XA – CD-XA is a CD-ROM extension being designed to support digital
audio and still images. Announced in August 1988 by Microsoft, Philips,
and Sony, the CD-ROM XA (for Extended Architecture) format incorporates
audio from the CD-I format. It is consistent with ISO 9660, (the volume and
the structure of CD-ROM), is an application extension. CD-XA defines
another way of formatting sectors on a CD-ROM, including headers in the
sectors that describe the type (audio, video, data) and some additional info
(markers, resolution in case of a video or audio sector, file numbers, etc.).
The data written on a CD-XA can still be in ISO9660 file system format and
therefore be readable by MSCDEX and UNIX CD-ROM file system translators.
A CD-I player can also read CD-XA discs even if its file system only
resembles ISO9660 and isn’t fully compatible. However, when a disc is
inserted in a CD-I player, the player tries to load an executable application
from the CD-XA, normally some 68000 application in the /CDI directory. Its
name is stored in the disc’s primary volume descriptor. CD-XA bridge discs,