Dynamic Range Compression Characteristics Using an Interpolating Polynomial for Digital Audio Systems

Shugang WEI  Kensuke SHIMIZU 

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences  Vol.E88-A  No.2  pp.586-589
Publication Date: 2005/02/01
Online ISSN: 
Print ISSN: 0916-8508
Type of Manuscript: LETTER
Category: Digital Signal Processing
Keyword: 
dynamic range control,  compression characteristic,  interpolating polynomial,  digital audio system,  gain, 

Full Text: PDF(117.9KB)

Summary: 
An audio signal level compressor is presented, which is based on the approximation algorithm using an interpolating polynomial. To implement a compression characteristic in a digital audio system, a power calculation with fractional numbers is required and it is difficult to be performed directly in digital circuits. We introduce a polynomial expression to approximate the power operation, then the gain calculation is easily performed with a number of additions, multiplications and a division. Newton's interpolation formula is used to calculate the compression characteristics in a very short time and the obtained compression characteristics are very close to the ideal ones.