Ensemble Designs 9455 3G Clean and Quiet Protection Switch - Manual (Page 55)

www.ensembledesigns.com 7435 and 9455 - page 55
Model 7435 and 9455 Clean and Quiet Protection Switches
Glossary
AES/EBU
The digital audio standard defined as a joint effort of the Audio Engineering Society and the
European Broadcast Union. AES/EBU or AES3 describes a serial bitstream that carries two audio
channels, thus an AES stream is a stereo pair. The AES/EBU standard covers a wide range of sample
rates and quantizations (bit depths). In television systems, these will generally be 48 KHz and either
20 or 24 bits.
AFD
Active Format Description is a method to carry information regarding the aspect ratio of the video
content. The specification of AFD was standardized by SMPTE in 2007 and is now beginning to
appear in the marketplace. AFD can be included in both SD and HD SDI transport systems. There is no
legacy analog implementation. (See WSS).
ASI
A commonly used transport method for MPEG video streams, ASI or Asynchronous Serial Interface,
operates at the same 270 Mb/s data rate as SD SDI. This makes it easy to carry an ASI stream through
existing digital television infrastructure. Known more formally as DVB-ASI, this transport mechanism
can be used to carry multiple program channels.
Aspect Ratio
The ratio of the vertical and horizontal measurements of an image. 4:3 is the aspect ratio for standard
definition video formats and television and 16:9 for high definition. Converting formats of unequal
ratios is done by letterboxing (horizontal bars) or pillar boxing (vertical pillars) in order to keep the
original format’s aspect ratio.
Bandwidth
Strictly speaking, this refers to the range of frequencies (i.e. the width of the band of frequency) used
by a signal, or carried by a transmission channel. Generally, wider bandwidth will carry and reproduce
a signal with greater fidelity and accuracy.
Beta
Sony Beta SP video tape machines use an analog component format that is similar to SMPTE, but
differs in the amplitude of the color difference signals. It may also carry setup on the luminance
channel.
Bit
A binary digit, or bit, is the smallest amount of information that can be stored or transmitted digitally
by electrical, optical, magnetic, or other means. A single bit can take on one of two states: On/Off,
Low/High, Asserted/ Deasserted, etc. It is represented numerically by the numerals 1 (one) and
0 (zero). A byte, containing 8 bits, can represent 256 different states. The binary number 11010111,
for example, has the value of 215 in our base 10 numbering system. When a value is carried digitally,
each additional bit of resolution will double the number of different states that can be represented.