Comparison of metrics for the evaluation of similarity in acoustic pressure signals

Determining if aeroacoustic sound predictions are accurate is difficult because the question of how to define ‘accurate’ remains open. This communication evaluates four metrics for comparing time-domain pressure signals, each implying its own definition of ‘accurate.’ An adaptation of a Structural Similarity Metric (originating from the image processing literature) to time–frequency representations of acoustic signals is shown to outperform typical metrics such as relative energy and mean square error.