Open Access

Lilia Lajmi, Stefan Roth

• Over time, the Constant Quality Transform (CQT) has established itself as a useful tool in audio signal processing, with a variety of methods proposed to reduce computational complexity, increase its accuracy and improve its usability. The aim of this review is to compare three different CQT-based transformations in order to gain further insight on how differences in the implementation affect frequency and amplitude accuracy in terms of computation time. All methods are implemented with the same parameter set in a MATLAB framework to transform short audio frames and compute the relative deviation in amplitude and frequency in order to establish a level playing field. The results show that the limitation of the window length to the number of available samples does not only reduces the computation time, but also keeps the accuracy at a comparable level. The results are then evaluated and discussed to inspire further analysis, discussion, and verification.