Objective:

This project is part of a project cluster that investigates time-frequency masking in the auditory system, in cooperation with the Laboratory for Mechanics and Acoustics / CNRS Marseille. While other subprojects study the spread of masking across the time-frequency plane using Gaussian-shaped tones, this subproject investigates how multiple Gaussian maskers distributed across the time-frequency plane create masking that adds up at a given time-frequency point. This question is important in determining the total masking effect resulting from the multiple time-frequency components (that can be modeled as Gaussian Atoms) of a real-life signal.

Method:

Both the maskers and the target are Gaussian-shaped tones with a frequency of 4 kHz. A two-stage approach is applied to measure the additivity of auditory masking. In the first stage, the levels of the maskers are adjusted to cause the same amount of masking in the target. In the second stage, various combinations of those maskers are tested to study their additivity.

In the first study, the maskers are spread either in time OR in frequency. In the second study, the maskers are spread in time AND in frequency.

Application:

New insight into the coding of sound in the auditory system could help to design more efficient audio codecs. These codecs could take the additivity of time-frequency masking into account.

Funding:

WTZ (project AMADEUS)

Publications:

  • Laback, B., Balazs, P., Toupin, G., Necciari, T., Savel, S., Meunier, S., Ystad, S., Kronland-Martinet, R. (2008). Additivity of auditory masking using Gaussian-shaped tones, presented at Acoustics? 08 conference, Paris.