A-Law

A-law is one of the two standard G.711 versions. The a-law codec is similar to the u-law algorithm which is used for digital communication and telephony in South America and Japan. However, the main difference between the two besides the countries that utilize them is that u-law has a slightly larger dynamic range.

Generally speaking, dynamic range is the ratio of the loudest sound without distortion over the background noise. For given bits, encoding with an a-law algorithm reduces the dynamic range of an audio signal, which increases coding efficiency and provides a higher signal-to-distortion ratio than linear encoding. The A-law compression ensures the same noise level while allowing for a clearer sound without distortion.

A-law is used in telephony and telecommunication for both newer digital and older analog systems. Once a digital computer system receives the sound, an analog-based system converts analog signals into digital ones. In accordance with the a-law algorithm, quantization levels must be set for the analog signal in an unequal space. It is done through the use of a nonlinear gain amplifier.

If the audio signal is already digitalized, there is no need to compress it. The symbol size of most computers can easily recognize an 8-bit digital data file.

Some benefits of audio processing using the a-law algorithm include: