Download Separation of musical notes with highly overlapping partials using phase and temporal constrained complex matric factorization In note separation of polyphonic music, how to separate the overlapping partials is an important and difficult problem. Fifths and octaves, as the most challenging ones, are, however, usually seen in many cases. Non-negative matrix factorization (NMF) employs the constraints of energy and harmonic ratio to tackle this problem. Recently, complex matrix factorization (CMF) is proposed by combining the phase information in source separation problem. However, temporal magnitude modulation is still serious in the situation of fifths and octaves, when CMF is applied. In this work, we investigate the temporal smoothness model based on CMF approach. The temporal ac-tivation coefficient of a preceding note is constrained when the succeeding notes appear. Compare to the unconstraint CMF, the magnitude modulation are greatly reduced in our computer simulation. Performance indices including sourceto-interference ratio (SIR), source-to-artifacts ratio (SAR), sourceto-distortion ratio (SDR), as well as modulation error ratio (MER) are given.
Download Unsupervised Audio Key and Chord Recognition This paper presents a new methodology for determining chords of a music piece without using training data. Specifically, we introduce: 1) a wavelet-based audio denoising component to enhance a chroma-based feature extraction framework, 2) an unsupervised key recognition component to extract a bag of local keys, 3) a chord recognizer using estimated local keys to adjust the chromagram based on a set of well-known tonal profiles to recognize chords on a frame-by-frame basis. We aim to recognize 5 classes of chords (major, minor, diminished, augmented, suspended) and 1 N (no chord or silence). We demonstrate the performance of the proposed approach using 175 Beatles’ songs which we achieved 75% in F-measure for estimating a bag of local keys and at least 68.2% accuracy on chords without discarding any audio segments or the use of other musical elements. The experimental results also show that the wavelet-based denoiser improves the chord recognition rate by approximately 4% over that of other chroma features.