Hello! This repository contains the MATLAB files relative to the implementation of the method proposed in the paper "Adaptive Loudness Compensation in Music Listening" presented at SMC 2019 (http://smc2019.uma.es/articles/S2/S2_01_SMC2019_paper.pdf).

Contacts and info: [email protected]

The need for loudness compensation is a well known fact arising from the nonlinear behavior of human sound perception. Music and other sounds are mixed and mastered at a certain loudness level, usually louder than the level at which they are commonly played. This implies a change in the perceived spectral balance of the sound, which is largest in the low-frequency range. As the volume setting in music playing is decreased, a loudness compensation filter can be used to boost the bass appropriately, so that the low frequencies are still heard well and the perceived spectral balance is preserved. This repo includes a loudness compensation function derived from the standard equal-loudness-level contours and its implementation via a digital first-order shelving filter.

• ellc.m: generates an Equal Loudness Contour as described in ISO 226/2003.
• OLA.m: performs the reconstruction of a signal that was buffered with the overlapp-and-add (OLA) method.
• traceLoudness.m: returns filtering trace-guide from ELLC (Equal-loudness level contours), as described in the paper.
• shelf1low.m: first order low-frequency shelving filter, as proposed by Valimaki and Reiss in "All About Audio Equalization: Solutions and Frontiers", Applied Sciences, 2016.
• adaptiveLoudnessComp.m: applies adaptive loudness compensation to the selected track according to reproduction level.