Definitions – Extron Electronics SME 100 User Guide User Manual
Page 13
Definitions
Advanced Audio Coding (AAC) — A standardized compression and encoding scheme for
lossy (low quality) digital audio.
Advanced Video Coding (AVC) — See the H.264 (MPEG-4 AVC) definition.
Bandwidth — A measure of available (or used) data communication resources in bit / s.
Bit rate — The number of bits that are conveyed or processed per unit of time. Bit rate is
quantified using the bits per second (bit / s) unit, often in conjunction with an SI prefix such
as kilo- (kbit / s or kbps), mega- (Mbit / s or Mbps), or giga- (Gbit / s or Gbps).
Compression — The science of reducing the amount of data required to represent a
picture (or a stream of pictures) and sound before sending or storing it.
Constant Bit Rate (CBR) — This scheme adjusts the output bit rate so that it stays very
close to the specified target bit rate.
Constrained Variable Bit Rate (CVBR) — This scheme is similar to Variable Bit Rate
(VBR), but sets a maximum allowed bit rate that the SME 100 cannot exceed.
Darwin Streaming Server (DSS) — Darwin Str
) is
software developed by Apple
®
that provides a high performance media streaming server
for delivering content. The software is used to simultaneously stream to a broad range of
screens and devices (including computers, televisions, smartphones, and tablets).
Domain Name System (DNS) — A database system that translates domain names
(such as
esses.
Dynamic Host Configuration Protocol (DHCP) — A network protocol that enables
a server to automatically assign unique network addresses (IP address, subnet mask,
gateway) to a device using a defined range of numbers configured for the network.
Elementary Stream — Raw H.264 video or raw AAC audio, not wrapped by additional
headers.
Extended Display Identification Data (EDID) — Data structure used to communicate
video display information (including native resolution and vertical interval refresh rate
requirements) to a source device. The source device will then output the optimal video
format for the display based on the provided EDID, ensuring proper video image quality.
File Transfer Protocol (FTP) — A protocol that is used to transfer files from one host to
another host over a TCP-based network (such as the Internet).
Gateway — A network node equipped for interfacing with another network that uses
different protocols (an entrance and exit into a communications network).
Group of Pictures (GOP) — A group of successive pictures within a coded video stream.
A GOP begins with an I-frame containing the full temporal resolution and data of a video
frame. Predictive frames (P-frames) follow I-frames and contain data that has changed from
the preceding I-frame.
H.264 (MPEG-4 AVC) — A block oriented, motion-compression-based codec standard
developed by the ITU-T Video Coding Experts Group (VCEG) together with the ISO / IEC
Moving Picture Experts Group (MPEG).
HDTV 1080p/60 — Stands for high definition television displayed at 1920x1080 resolution
(1080p; 2,073,600 pixels) with a refresh rate of 60 Hz.
Hop — In a packet-switching network, a hop is the trip a data packet takes from one router
(or intermediate point) to another in the network.
Hypertext Transfer Protocol (HTTP) — A networking protocol that allows web servers to
transfer and display web content to users.
SME 100 • Introduction
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