An efficient time-varying loudness model

In this paper, we present an efficient loudness model applicable to time-varying sounds. We use the model of Glasberg and Moore (J. Audio Eng. Soc., 2002) as the basis for our developments, proposing a number of optimization techniques to reduce the computational complexity at each stage of the model. Efficient alternatives to computing the multi-resolution DFT, excitation pattern and pre-cochlea filter are presented. Absolute threshold and equal loudness contour predictions are computed and compared against both steady-state and time-varying loudness models to evaluate the combined accuracy of these techniques in the frequency domain. Finally, computational costs and loudness errors are quantified for a range of time-varying stimuli, demonstrating that the optimized model can execute approximately 50 times faster within tolerable error bounds.