Noise Morphing for Audio Time Stretching

TL;DR

This paper presents a novel noise morphing technique for audio time stretching that improves quality, especially in extreme stretch scenarios, by decomposing sound into components and morphing the noise part.

Contribution

It introduces a simple, efficient method to enhance noise processing in audio time stretching by combining sound decomposition with spectral resynthesis techniques.

Findings

Subjective tests show superior quality over state-of-the-art methods.

Method performs well across all stretch factors.

Significant improvements in extreme stretching scenarios.

Abstract

This letter introduces an innovative method to enhance the quality of audio time stretching by precisely decomposing a sound into sines, transients, and noise and by improving the processing of the latter component. While there are established methods for time-stretching sines and transients with high quality, the manipulation of noise or residual components has lacked robust solutions in prior research. The proposed method combines sound decomposition with previous techniques for audio spectral resynthesis. The time-stretched noise component is achieved by morphing its time-interpolated spectral magnitude with a white-noise excitation signal. This method stands out for its simplicity, efficiency, and audio quality. The results of a subjective experiment affirm the superiority of this approach over current state-of-the-art methods across all evaluated stretch factors. The proposed technique notably excels in extreme stretching scenarios, signifying a substantial elevation in performance. The proposed method holds promise for a wide range of applications in slow-motion media content, such as music or sports video production.