Automatic parameter optimization for a perceptual audio codec

In audio codec design, often various parameters have to be fixed which may have a dramatic impact on codec performance. In this paper, we report on successful optimization of a codec based on perceptual criteria. Specifically, the PEAQ measure is used to determine the audio quality over a set of test items and search algorithms are used for optimization. First, simulated annealing is used for global search, then Rosenbrock's method is used to further refine the result. As shown by an example, the improvements gained by optimization compared to an educated guess are substantial.