Webopedia on Google+Webopedia on TwitterWebopedia on FacebookTech Bytes Blog
Main » TERM » G »

G.721

An International Telecommunications Union (ITU-T) standard for for audio (speech) compression and decompression that is used in digital transmission systems, and in particular, used for the coding of analogsignals into digital signals.

G.721 is an ITU-T standard codec that uses Adaptive Differential Pulse Code Modulation (ADPCM); a form of Pulse Code Modulation (PCM), to produce a digital signal with a lower bit rate than standard PCM. This ITU standard for speech codecs uses ADPCM on a  32 kbit/s channel. NOTE: G.721 was first introduced in 1984. In 1990 this standard was folded into G.726 along with G.723. (See also ADPCM).

See G.7xx for more information on how these standards are used in telephony networks.







TECH RESOURCES FROM OUR PARTNERS
LATEST ARTICLES
Slideshow: History of Microsoft Operating Systems

Microsoft Windows is a family of operating systems for personal computers. In this article we look at the history of Microsoft operating... Read More »

Slideshow: Interesting Facts About Google Search

From Goats to Penguins, a server outage and trillions of searches, our slideshow presents interesting facts about Google and the Google.com... Read More »

Slideshow: 5 Apps to Make Your Commute a Breeze

We've scoured the App and Play Stores to bring you five of the most useful apps to have with you on the road, plus a bonus in-car feature. Read More »

STUDY GUIDES
Java Basics, Part 1

Java is a high-level programming language. This guide describes the basics of Java, providing an overview of syntax, variables, data types and... Read More »

Java Basics, Part 2

This second Study Guide describes the basics of Java, providing an overview of operators, modifiers and control Structures. Read More »

The 7 Layers of the OSI Model

The Open System Interconnection (OSI) model defines a networking framework to implement protocols in seven layers. Use this handy guide to compare... Read More »