Download Model-based event labeling in the transcription of percussive audio signals In this paper we describe a method for the transcription of percussive audio signals which have been performed with arbitrary nondrum sounds. The system locates sound events from the input signal using an onset detector. Then a set of features is extracted from the onset times. Feature vectors are clustered and the clusters are assigned with labels which describe the rhythmic role of each event. For the labeling, a novel method is proposed which is based on metrical (temporal) positions of the sound events within the measures. The system is evaluated using monophonic percussive tracks consisting of non-drum sounds. In simulations, the system achieved a total error rate of 33.7%. Demo signals are available at URL:<http://www.cs.tut.fi/~paulus/demo/>.
Download Estimation of tempo, micro time and time signature from percussive music Tempo, micro time and time signature are basic rhythmic features for a wide range of music. Their automated extraction from music is needed for a number of applications, e.g. automatic transcription and music information retrieval systems, authoring tools, entertainment applications, musicological analysis or educational purposes. The presented analysis procedure estimates tempo, micro time and time signature from percussive music. From 117 excerpts of eight seconds length, 84.6% of the tempo values, 83.8% of the micro time and 73.5% of the time signatures were estimated correctly.
Download Complex domain onset detection for musical signals We present a novel method for onset detection in musical signals. It improves over previous energy-based and phase-based approaches by combining both types of information in the complex domain. It generates a detection function that is sharp at the position of onsets and smooth everywhere else. Results on a handlabelled data-set show that high detection rates can be achieved at very low error rates. The approach is more robust than its predecessors both theoretically and practically.
Download Rhythmic expressiveness transformations of audio recordings: swing modifications In this paper, we propose a computer software for modifying rhythmic performances of polyphonic musical audio signals. It first describes the rhythmic content of an audio signal (i.e. determination of tempi and beat indexes at the quarter-note and eighth-note levels, as well as estimation of the swing ratio). Then, the signal is transformed in real-time using a time-stretch algorithm. We present basic techniques provided by commercial products for swing modification and compare these to our system.
Download MUSESCAPE: An interactive content-aware music browser Advances in hardware performance, network bandwidth and audio compression have made possible the creation of large personal digital music collections. Although, there is a significant body of work in image and video browsing, there has been little work that directly addresses the problem of audio and especially music browsing. In this paper, Musescape, a prototype music browsing system is described and evaluated. The main characteristics of the system are automatic configuration based on Computer Audition techniques and the use of continuous audio-music feedback while browsing and interacting with the system. The described ideas and techniques take advantage of the unique characteristics of music signals. A pilot user study was conducted to explore and evaluate the proposed user interface. The results indicate that the use of automatically extracted tempo information reduces browsing time and that continuous interactive audio feedback is appropriate for this particular domain.
Download Driving pitch-shifting and time-scaling algorithm with adaptive and gestural techniques This article intends to demonstrate how a specific digital audio effect can benefit from a proper control, be it from sounds and/or from gesture. When this control is from sounds, it can be called “adaptive” or “sound automated”. When this control is from gesture, it can be called “gesturally controlled”. The audio effects we use for this demonstration are time-scaling and pitch-shifting in the particular contexts of vibrato, prosody change, time unfolding and rythm change.
Download CYMATIC: A tactile controlled physical modelling instrument The recent trend towards the virtual in music synthesis has lead to the inevitable decline of the physical, inserting what might be described as a ‘veil of tactile paralysis’ between the musician and the sound source. The addition of tactile and gestural interfaces to electronic musical instruments offers the possibility of moving some way towards reversing this trend. This paper describes a new computer based musical instrument, known as Cymatic, which offers gestural control as well as tactile and proprioceptive feedback via a force feedback joystick and a tactile feedback mouse. Cymatic makes use of a mass/spring physical modelling paradigm to model multi-dimensional, interconnectable resonating structures that can be played in real-time with various excitation methods. It therefore restores to a degree the musician’s sense of working with a true physical instrument in the natural world. Cymatic has been used in a public performance of a specially composed work, which is described.
Download Introducing Audio D-TOUCH: A tangible user interface for music composition and performance "Audio d-touch" uses a consumer-grade web camera and customizable block objects to provide an interactive tangible interface for a variety of time based musical tasks such as sequencing, drum editing and collaborative composition. Three instruments are presented here. Future applications of the interface are also considered.
Download Additive synthesis based on the continuous wavelet transform: A sinusoidal plus transient model In this paper a new algorithm to compute an additive synthesis model of a signal is presented. An analysis based on the Continuous Wavelet Transform (CWT) has been used to extract the time-varying amplitudes and phases of the model. A coarse to fine analysis increases the algorithm efficiency. The computation of the transient analysis is performed using the same algorithm developed for the sinusoidal analysis, setting the proper parameters. A sinusoidal plus transient schema is obtained. Typical sound transformations have been implemented to validate the obtained results.