International Journal of Computer Theory and Engineering

Abstract

In this paper, we propose a new melody contour extraction technique and new normalization methods to improve Query-by-Humming. A critical issue of humming sound is noise interference from both environment and acquisition instruments. Furthermore, most users are not professional singers therefore they cause the other query problems about variation of pitch and timing. Advantage of the proposed technique can reduce noise whereas makes pitch smoothing. Our technique consists of four steps as follows: Firstly, the melody contour is extracted from humming sound by Subharmonic-to-Harmonic Ratio (SHR).Subsequently, the melody contour is filtered and smoothed by median filter and our propose technique. Afterwards, we used various normalization methods, including our new techniques, for scaling and noise robust. Finally, humming sound and melody sequences are different alignment methods such as Dynamic Time Warping (DTW), linear interpolations and nonlinear interpolations, before classification. Our technique offers several advantages: higher accuracy, lower complexity, faster query process and lower memory. In addition, the experimental results show that our proposed technique can perform more effective than other methods.