Companding

 • What is companding ?

Companding refers to a technique for compressing and then expanding (or decompressing) an analog or digital signal. It is a combination of the words "compressing" and "expanding."

• Types of companding :

There are two types of companding

* A law Companding

* μ-law companding

• Why is companding needed ?

Companding is a common technique for reducing the data rate of Audio signals by making the quantization level unequal. 

• Applications :

* Companding is used in digital telephony systems, compressing before input to an Analog to digital converter, and then expanding after a digital to analog converter.

* This method is also used in digital file formats for better signal-to-noise ratio (SNR) at lower bit rates.

* Companders are used in concert audio systems and in some noise reduction schemes.