Time-scaling of Audio Signals with Muti-scale Gabor Analysis
نویسنده
چکیده
The phase vocoder is a standard frequency domain time-scaling technique suitable for polyphonic audio, but it generates annoying artifacts called phasiness, or loss of presence, and transient smearing, especially for high values of the time-scale parameter. In this paper, a new time-scaling algorithm for polyphonic audio signals is described. It uses a multi-scale Gabor analysis for lowfrequency content and a vocoder with phase-locking on transients for the residual signal and for high-frequency content. Compared to a phase-locking vocoder alone, our method significantly reduces both phasiness and transient smearing, especially for high values of the time-scale parameter. For time-contraction (time-scale parameters lower that one), the results seem to be more signaldependant.
منابع مشابه
Multi-gabor Dictionaries for Audio Time-frequency Analysis
In this paper we consider the construction of multiresolution Gabor dictionaries appropriate for audio signal analysis. Motivated by a desire for parsimony and efficiency, we propose and formalise the idea of reduced multi-Gabor systems, showing that they constitute a frame for L2(R) and other Hilbert spaces of interest. In order to demonstrate the practicality of such a scheme, we apply it to ...
متن کاملHarmonic decomposition of audio signals with matching pursuit
We introduce a dictionary of elementary waveforms, called harmonic atoms, that extends the Gabor dictionary and fits well the natural harmonic structures of audio signals. By modifying the “standard” matching pursuit, we define a new pursuit along with a fast algorithm, namely the Fast Harmonic Matching Pursuit, to approximate N-dimensional audio signals with a linear combination of M harmonic ...
متن کاملSparsity and persistence in time-frequency sound representations
It is a well known fact that the time-frequency domain is very well adapted for representing audio signals. The main two features of time-frequency representations of many classes of audio signals are sparsity (signals are generally well approximated using a small number of coefficients) and persistence (significant coefficients are not isolated, and tend to form clusters). This contribution pr...
متن کاملTime Scale Modiication Using a Sines+transients+noise Signal Model
We propose a method for the time scaling of digitally sampled audio signals using a three part signal model consisting of sines+transients+noise. The three part model provides an accurate and exible parametric representation for a wide range of audio signals. Because the proposed time scaling method manipulates each of the model components separately, the method allows modiied tonal components ...
متن کاملA Hybrid Time-Frequency Domain Approach to Audio Time-Scale Modification*
Frequency-domain approaches to audio time-scale modification introduce a reverberant/phasy artefact into the time-scaled output. Such artefacts are generally not present within time-domain implementations; however, high quality time-scaling in the timedomain is typically limited to quasi-periodic signals such as speech. A hybrid method of time-scaling is presented which draws upon appealing asp...
متن کامل