Time-frequency synthesis of noisy sounds with narrow spectral components
Résumé
The inverse FFT method was proposed to alleviate the computational complexity of the additive sound synthesis method in real time applications, and consists in synthesizing overlapping blocks of samples in the frequency domain. However, its application is limited by its inherent trade-off between time and frequency resolution. In this paper we propose an alternative to the inverse FFT method for synthesizing colored noise. The proposed approach uses subband signal processing to generate time-frequency noise with an auto-correlation function such that the noise obtained after converting it to time domain has the desired power spectral density. We show that the inverse FFT method can be interpreted as a particular case of the proposed method, and therefore, the latter offers some extra design flexibility. Exploiting this property, we present experimental results showing that the proposed method can offer a better trade-off between time and frequency resolution, at the expense of some extra computations.