Autoregressive hidden semi-Markov model of symbolic music performance for score following

International audienceA stochastic model of symbolic (MIDI) performance of polyphonic scores is presented and applied to score following. Stochastic modelling has been one of the most successful strategies in this field. We describe the performance as a hierarchical process of performer's progression in the score and the production of performed notes, and represent the process as an extension of the hidden semi-Markov model. The model is compared with a previously studied model based on hidden Markov model (HMM), and reasons are given that the present model is advantageous for score following especially for scores with trills, tremolos, and arpeggios. This is also confirmed empirically by comparing the accuracy of score following and analysing the errors. We also provide a hybrid of this model and the HMM-based model which is computationally more efficient and retains the advantages of the former model. The present model yields one of the state-of-the-art score following algorithms for symbolic performance and can possibly be applicable for other music recognition problems

Perspectives of electroacoustic music : a critical study of the electroacoustic music of Jonathan Harvey, Denis Smalley and Trevor Wishart.

SIGLEAvailable from British Library Document Supply Centre- DSC:D174894 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Analysis and resynthesis of polyphonic music

This thesis examines applications of Digital Signal Processing to the analysis, transformation, and resynthesis of musical audio. First I give an overview of the human perception of music. I then examine in detail the requirements for a system that can analyse, transcribe, process, and resynthesise monaural polyphonic music. I then describe and compare the possible hardware and software platforms. After this I describe a prototype hybrid system that attempts to carry out these tasks using a method based on additive synthesis. Next I present results from its application to a variety of musical examples, and critically assess its performance and limitations. I then address these issues in the design of a second system based on Gabor wavelets. I conclude by summarising the research and outlining suggestions for future developments

Gestural extraction from musical audio signals

Conventional exploration of gestures normally associated with musical instruments can be a costly and intrusive process. This thesis presents a novel approach to gestural extraction which overcomes these problems. The motivation behind this research is that the result of gestural input can be heard and therefore extracted from the acoustic signal produced by a musical instrument. Therefore, the guiding principles of this work are taken from the human auditory system. The concept of temporal grouping, and the fact that any sound which reaches the inner ear is conveyed to the brain, are two features of the auditory system that are mimicked by the presented system. Pertinent definitions are proposed for the sections of the note envelope and musical instrument gestures are classified according to those responsible for excitation or control. The extraction of gestural information is dependent upon successful identification of note events. A note tracking system is presented which exploits the structure of a note in order to perform preliminary note onset detection. A backtracking function is employed to regress through auditory data, providing a means of assigning individual start points to each note harmonic. The note tracking system also records the end point of each note harmonic. Note information is validated by a bespoke musical comparison system which provides a means of comparing and evaluating different note detection methods. Information provided by the note tracking system is used to extract gestural information regarding oboe key presses and excitation (articulation) methods of string instruments. System tests show that it is possible to correctly distinguish between bowed and plucked notes with an 89% success rate, using only three discriminators associated with the onset of a note. In this thesis the foundations of a multifacetted gestural extraction system are presented with useful potential for further development

Algorithmen zur Synchronisation von Musikdaten im Partitur-, MIDI- und PCM-Format

Digitalisierung und weltweite Vernetzung haben zu einer Flut von Daten höchst unterschiedlichen Inhalts und Formats geführt, die es durch gezielte multimediale Techniken sinnvoll zu nutzen gilt. Dabei stellen allerdings die Inhomogenität und Komplexität der vorliegenden Daten große Problemen dar. Zum Beispiel können im Fall des Datentyps Audio, um den es in der vorliegenden Arbeit geht, verschiedene Versionen ein und desselben Musikstücks in unterschiedlichen Datenformaten vorliegen; hier seien z.B. Partiturformat, MIDI-Format oder wellenformbasierte Datenformate wie das PCM-Format genannt. Für die inhaltsbasierte Suche in inhomogenen Musikdatenbänken werden Synchronisationsalgorithmen benötigt, die solche Daten unterschiedlicher Formate automatisch verlinken. Hierbei verstehen wir unter Synchronisation ein Verfahren, das zu einer bestimmten Position innerhalb einer Darstellung eines Musikstücks (z.B. in einem PCM-Datensatz) die entsprechende Stelle innerhalb einer anderen Darstellung (z.B. MIDI-Datensatz) bestimmen kann. In unserem Verfahren extrahieren wir vor der eigentlichen Synchronisation unter Verwendung von Multiraten-Filterbänken und Notenschablonen eine geeignete Menge an Notenereignissen (Kandidaten für Einsatzzeiten und Tonhöhen) aus der PCM-Darstellung, um so die PCM-Daten mit partiturähnlichen Daten überhaupt erst vergleichbar und algorithmisch zugänglich zu machen. Um die Synchronisation robust gegenüber unscharfen (impliziten) Notenereignissen in der Partitur (wie z.B. Triller, Arpeggien oder Verzierungen) zu machen, werden diese mittels sogenannter Fuzzy-Noten modelliert und gesondert behandelt. MIDI-Dateien und die PCM-Extraktionsdaten müssen aus technischen Gründen sowie zur Steigerung der Robustheit zeitquantisiert werden. Auf den so vorverarbeiteten Daten werden nun auf der Basis geeigneter Kostenfunktionen mittels dynamischer Programmierung kostenoptimale zeitliche Verlinkungen (Matchings) berechnet. Unser Verfahren wurde in MATLAB implementiert und anhand zahlreicher Beispiele unterschiedlicher Komplexität getestet

Live electronics in live performance : a performance practice emerging from the piano+ used in free improvisation

This thesis explores a performance practice within free improvisation. This is not a theory based improvisation – performances do not require specific preparation and the music refrains from repetition of musical structures. It engages in investigative and experimental approaches emerging from holistic considerations of acoustics, interaction and instrument, and also philosophy, psychology, sociopolitics and technology. The performance practice explores modes and approaches to working with the given potentiality of an electronically augmented acoustic instrument and involves the development of a suitably flexible computerised performance system, the piano+, combining extended techniques and real-time electroacoustic processes, which has the acoustic piano at its core. Contingencies of acoustic events and performance gestures – captured by audio analysis and sensors and combined to control the parameter space of computer processes – manipulate the fundamental properties of sound, timbre and time. Spherical abstractions, developed under consideration of Agamben’s potentiality and Sloterdijk’s philosophical theory of spheres, allow a shared metaphor for technical, instrumental, personal, and interpersonal concerns. This facilitates a theoretical approach for heuristic and investigative improvisation where performance is considered ‘Ereignis’ (an event) for sociopolitically aware activities that draw on the situational potentiality and present themselves in fragile and context dependent forms. Ever new relationships can be found and developed, but can equally be lost. Sloterdijk supplied the concept of knowledge resulting from equipping our ‘inner space’, an image suiting non-linearity of thought that transpires from Kuhl’s psychological PSI-theory to explain human motivation and behaviour. The role of technology – diversion and subversion of sound and activity – creates a space between performer and instrument that retains a fundamental pianism but defies expectation and anticipation. Responsibility for one’s actions is required to deal with the unexpected without resorting to preliminary strategies restricting potential discourses, particularly within ensemble situations. This type of performance embraces the ‘Ereignis’.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Live Electronics in Live Performance: A Performance Practice Emerging from the piano+ used in Free Improvisation.

This thesis explores a performance practice within free improvisation. This is not a theory based improvisation – performances do not require specific preparation and the music refrains from repetition of musical structures. It engages in investigative and experimental approaches emerging from holistic considerations of acoustics, interaction and instrument, and also philosophy, psychology, sociopolitics and technology. The performance practice explores modes and approaches to working with the given potentiality of an electronically augmented acoustic instrument and involves the development of a suitably flexible computerised performance system, the piano+, combining extended techniques and real-time electroacoustic processes, which has the acoustic piano at its core. Contingencies of acoustic events and performance gestures – captured by audio analysis and sensors and combined to control the parameter space of computer processes – manipulate the fundamental properties of sound, timbre and time. Spherical abstractions, developed under consideration of Agamben’s potentiality and Sloterdijk’s philosophical theory of spheres, allow a shared metaphor for technical, instrumental, personal, and interpersonal concerns. This facilitates a theoretical approach for heuristic and investigative improvisation where performance is considered ‘Ereignis’ (an event) for sociopolitically aware activities that draw on the situational potentiality and present themselves in fragile and context dependent forms. Ever new relationships can be found and developed, but can equally be lost. Sloterdijk supplied the concept of knowledge resulting from equipping our ‘inner space’, an image suiting non-linearity of thought that transpires from Kuhl’s psychological PSI-theory to explain human motivation and behaviour. The role of technology – diversion and subversion of sound and activity – creates a space between performer and instrument that retains a fundamental pianism but defies expectation and anticipation. Responsibility for one’s actions is required to deal with the unexpected without resorting to preliminary strategies restricting potential discourses, particularly within ensemble situations. This type of performance embraces the ‘Ereignis’

New Techniques for Enhanced Quality of Computer Accompaniment

A computer accompaniment system has been extended with several techniques to solve problems associated with reliably recognizing and following a real-time performance. One technique is the use of an additional matcher to consider alternatives when the performance could be interpreted in two ways. Another is to delay corrective action when data from the matcher is suspect. Methods for handling grace notes, trills, and glissandi are also presented. The implementation of these and other techniques to produce an enhanced computer accompaniment system is discussed. 1. Introduction The basic technology for real-time computer accompaniment 1 of live musicians was first presented in 1984 [1, 2], however the first systems left a lot of room for improvement. We have been developing new computer accompaniment systems for two years in an effort to obtain higher reliability in the accompanist and also to deal with a more complete musical vocabulary. Like the first systems, the task is to accept a..

New Techniques for Enhanced Quality of Computer Accompaniment

A computer accompaniment system has been extended with several techniques to solve problems associated with reliably recognizing and following a real-time performance. One technique is the use of an additional matcher to consider alternatives when the performance could be interpreted in two ways. Another is to delay corrective action when data from the matcher is suspect. Methods for handling grace notes, trills, and glissandi are also presented. The implementation of these and other techniques to produce an enhanced computer accompaniment system is discussed. 1