Time-scale modification of music signals

Time-scale modification (TSM) of audio signals is the process of modifying the rate of audio signals such as speech or music, while maintaining other parameters (pitch, timbre) unchanged. It is a subject of major theoretical and practical interest. In this study, a new algorithm for time-scale modification of music signals is presented. The proposed algorithm is related to the PSOLA-like algorithms, which are based on the similarity of the short-time Fourier transform between the original and the timescaled signal. The basic assumption of these algorithms is that the spectral characteristics of the signal are constant for short durations, and that the signal is quasi-periodic in the time domain. The signal in PSOLA is divided into short-time overlapping frames, which are used for constructing the time-scaled synthesis signal, while maintaining the original spectral parameters and their related location.