Andrew Robertson - Academia.edu (original) (raw)

Papers by Andrew Robertson

They say it is a wise man who climbs Mount Fuji, but a fool who climbs it twice." I would like to... more They say it is a wise man who climbs Mount Fuji, but a fool who climbs it twice." I would like to express my extreme gratitude to my supervisor Prof. Mark Plumbley for his constant support and encouragement during the creation of this thesis. I'd like to take this opportunity to thank Dr. Nick Bryan-Kinns, Prof.

Proceedings of the SMC Conferences, Jul 30, 2013

Live music performance with computers has motivated many research projects in science, engineerin... more Live music performance with computers has motivated many research projects in science, engineering, and the arts. In spite of decades of work, it is surprising that there is not more technology for, and a better understanding of the computer as music performer. We review the development of techniques for live music performance and outline our efforts to establish a new direction, Human-Computer Music Performance (HCMP), as a framework for a variety of coordinated studies. Our work in this area spans performance analysis, synchronization techniques, and interactive performance systems. Our goal is to enable musicians to incorporate computers into performances easily and effectively through a better understanding of requirements, new techniques, and practical, performance-worthy implementations. We conclude with directions for future work.

Proceedings of the SMC Conferences, Jul 6, 2011

This paper describes a real-time Bayesian formulation of the problem of drum tracking. We describ... more This paper describes a real-time Bayesian formulation of the problem of drum tracking. We describe how drum events can be interpreted to update distributions for both tempo and phase, and how these distributions can be combined together in a real-time drum tracking system. Our algorithm is intended for the purposes of synchronisation of pre-recorded audio or video with live drums. We evaluate the algorithm of a new set of drum files from real recordings and compare it to other state-of-the-art algorithms. Our proposed method performs very well, often improving on the results of other real-time beat trackers. The algorithm is implemented in C++ and runs in real-time.

Proceedings of the SMC Conferences, Sep 14, 2014

This paper presents a methodology for predicting the pitch of bass notes by utilising their metri... more This paper presents a methodology for predicting the pitch of bass notes by utilising their metrical position within the bar. Our system assumes two separate audio channels for drums and bass. We make use of onset detection and beat tracking algorithms to determine the onset times for each bass note and the beat locations. A monophonic bass track is analysed for repetitive structures relative to the beat grid, enabling the system to make a prediction of the pitch of each bass note prior to any pitch-related analysis. We present an analysis on a small collection of studio recordings.

This research focuses on real-time gesture learning and recognition. Events arrive in a continuou... more This research focuses on real-time gesture learning and recognition. Events arrive in a continuous stream without explicitly given boundaries. To obtain temporal accuracy, weneed to consider the lag between the detection of an eventand any effects we wish to trigger with it. Two methodsfor real time gesture recognition using a Nintendo Wii controller are presented. The first detects gestures similar to agiven template using either a Euclidean distance or a cosinesimilarity measure. The second method uses novel information theoretic methods to detect and categorize gestures inan unsupervised way. The role of supervision, detection lagand the importance of haptic feedback are discussed.

Off-line beat trackers are often compared to human tappers who provide a ground truth against whi... more Off-line beat trackers are often compared to human tappers who provide a ground truth against which they can be judged. In order to evaluate a real-time beat tracker, we have taken the paradigm of the 'Turing Test' in which an interrogator is asked to distinguish between human and machine. A drummer plays in succession with an interactive accompaniment that has one of three possible tempocontrollers (the beat tracker, a human tapper and a steadytempo metronome). The test is double-blind since the researchers do not know which controller is currently functioning. All participants are asked to rate the accompaniment and to judge which controller they believe was responsible. This method for evaluation enables the controllers to be contrasted in a more quantifiable way than the subjective testimony we have used in the past to evaluate the system. The results of the experiment suggest that the beat tracker and a human tapper are both distinguishable from a steadytempo accompaniment and they are preferable according to the ratings given by the participants. Also, the beat tracker and a human tapper are not sufficiently distinguishable by any of the participants in the experiment, which suggests that the system is comparable in performance to a human tapper.

2012 3rd International Workshop on Cognitive Information Processing (CIP), 2012

We describe an information-theoretic approach to the analysis of music and other sequential data,... more We describe an information-theoretic approach to the analysis of music and other sequential data, which emphasises the predictive aspects of perception, and the dynamic process of forming and modifying expectations about an unfolding stream of data, characterising these using the tools of information theory: entropies, mutual informations, and related quantities. After reviewing the theoretical foundations, we discuss a few emerging areas of application, including musicological analysis, real-time beat-tracking analysis, and the generation of musical materials as a cognitively-informed compositional aid.

International Journal of Human-Computer Studies, 2009

Live music-making using interactive systems is not completely amenable to traditional HCI evaluat... more Live music-making using interactive systems is not completely amenable to traditional HCI evaluation metrics such as taskcompletion rates. In this paper we discuss quantitative and qualitative approaches which provide opportunities to evaluate the music-making interaction, accounting for aspects which cannot be directly measured or expressed numerically, yet which may be important for participants. We present case studies in the application of a qualitative method based on Discourse Analysis, and a quantitative method based on the Turing Test. We compare and contrast these methods with each other, and with other evaluation approaches used in the literature, and discuss factors affecting which evaluation methods are appropriate in a given context.

B-Keeper is a real-time beat-tracker for live performance with drums. The system maintains synchr... more B-Keeper is a real-time beat-tracker for live performance with drums. The system maintains synchronisation between a software sequencer and a drummer by analysing onsets form the kick drum and making small tempo changes. This system enables the sequencing of computer generated parts in time with the drums and provides a structure for real-time analysis for the purpose of integrating computers further into live performance.

We present a method for real-time pitch-tracking which generates an estimation of the relative am... more We present a method for real-time pitch-tracking which generates an estimation of the relative amplitudes of the partials relative to the fundamental for each detected note. We then employ a subtraction method, whereby lower fundamentals in the spectrum are accounted for when looking at higher fundamental notes. By tracking notes which are playing, we look for note off events and continually update our expected partial weightings for each note. The resulting algorithm makes use of these relative partial weightings within its decision process. We have evaluated the system against a data set and compared it with specialised offline pitch-trackers.

We present an overview of developments towards interactive musical systems. A description of an i... more We present an overview of developments towards interactive musical systems. A description of an interactive system is given and we consider potential uses for the automation of creative processes within live performance. We then look at the history of research into the problem of automatic accompaniment, discuss a variety of current interactive systems and present some ideas for future research.

Journal of New Music Research, 2015

This paper presents a Bayesian probabilistic framework for real-time alignment of a recording or ... more This paper presents a Bayesian probabilistic framework for real-time alignment of a recording or score with a live performance using an event-based approach. Multitrack audio files are processed using existing onset detection and harmonic analysis algorithms to create a representation of a musical performance as a sequence of time-stamped events. We propose the use of distributions for the position and relative speed which are sequentially updated in real-time according to Bayes' theorem. We develop the methodology for this approach by describing its application in the case of matching a single MIDI track and then extend this to the case of multitrack recordings. An evaluation is presented that contrasts our multitrack alignment method with state-of-theart alignment techniques.

Proceedings of the International Conference on New Interfaces for Musical Expression, 30 May - 1 June 2011, Oslo, Norway, 2011

This paper introduces the Seaboard, a new tangible musical instrument which aims to provide music... more This paper introduces the Seaboard, a new tangible musical instrument which aims to provide musicians with significant capability to manipulate sound in real-time in a musically intuitive way. It introduces the core design features which make the Seaboard unique, and describes the motivation and rationale behind the design. The fundamental approach to dealing with problems associated with discrete and continuous inputs is summarised

This paper introduces the Seaboard, a new tangible musical instrument which aims to provide music... more This paper introduces the Seaboard, a new tangible musical instrument which aims to provide musicians with signicant capability to manipulate sound in real-time in a musically intuitive way. It introduces the core design features which make the Seaboard unique, and describes the motivation and rationale behind the design. The fundamental approach to dealing with problems associated with discrete and continuous inputs is summarized.

This paper addresses the problem of determining tempo and timing data from a list of beat annotat... more This paper addresses the problem of determining tempo and timing data from a list of beat annotations. Whilst an approximation to the tempo can be calculated from the inter-beat interval, the annotations also include timing variations due to expressively timed events, phase shifts and errors in the annotation times. These deviations tend to propagate into the tempo graph and so tempo analysis methods tend to average over recent inter-beat intervals. However, whilst this minimises the effect such timing deviations have on the local tempo estimate, it also obscures the expressive timing devices used by the performer. Here we propose a more formal method for calculation of the optimal tempo path through use of an appropriate cost function that incorporates tempo change, phase shift and expressive timing.

This paper describes the development of B-Keeper, a reatime beat tracking system implemented in J... more This paper describes the development of B-Keeper, a reatime beat tracking system implemented in Java and Max/MSP, which is capable of maintaining synchronisation between an electronic sequencer and a drummer. This enables musicians to interact with electronic parts which are triggered automatically by the computer from performance information. We describe an implementation which functions with the sequencer Ableton Live.

2012 3rd International Workshop on Cognitive Information Processing (CIP), 2012

We describe an information-theoretic approach to the analysis of music and other sequential data,... more We describe an information-theoretic approach to the analysis of music and other sequential data, which emphasises the predictive aspects of perception, and the dynamic process of forming and modifying expectations about an unfolding stream of data, characterising these using the tools of information theory: entropies, mutual informations, and related quantities. After reviewing the theoretical foundations, we discuss a few emerging areas of application, including musicological analysis, real-time beat-tracking analysis, and the generation of musical materials as a cognitively-informed compositional aid.

Computer Music Journal, 2013

This article presents a method of adjusting the tempo of a music software sequencer so that it re... more This article presents a method of adjusting the tempo of a music software sequencer so that it remains synchronized with a drummer's musical pulse. This allows music sequencer technology to be integrated into a band scenario without the compromise of using click tracks or triggering loops with a fixed tempo. Our design implements real-time mechanisms for both underlying tempo and phase adjustment using adaptable parameters that control its behavior. The aim is to create a system that responds to timing variations in the drummer's playing but is also stable during passages of syncopation and fills. We present an evaluation of the system using a stochastic drum machine that incorporates a level of noise in the underlying tempo and phase of the beat. We measure synchronization error between the output of the system and the underlying pulse of the drum machine and contrast this with other real-time beat trackers. The software, B-Keeper, has been released as a Max for Live device...

They say it is a wise man who climbs Mount Fuji, but a fool who climbs it twice." I would like to... more They say it is a wise man who climbs Mount Fuji, but a fool who climbs it twice." I would like to express my extreme gratitude to my supervisor Prof. Mark Plumbley for his constant support and encouragement during the creation of this thesis. I'd like to take this opportunity to thank Dr. Nick Bryan-Kinns, Prof.

Proceedings of the SMC Conferences, Jul 30, 2013

Live music performance with computers has motivated many research projects in science, engineerin... more Live music performance with computers has motivated many research projects in science, engineering, and the arts. In spite of decades of work, it is surprising that there is not more technology for, and a better understanding of the computer as music performer. We review the development of techniques for live music performance and outline our efforts to establish a new direction, Human-Computer Music Performance (HCMP), as a framework for a variety of coordinated studies. Our work in this area spans performance analysis, synchronization techniques, and interactive performance systems. Our goal is to enable musicians to incorporate computers into performances easily and effectively through a better understanding of requirements, new techniques, and practical, performance-worthy implementations. We conclude with directions for future work.

Proceedings of the SMC Conferences, Jul 6, 2011

This paper describes a real-time Bayesian formulation of the problem of drum tracking. We describ... more This paper describes a real-time Bayesian formulation of the problem of drum tracking. We describe how drum events can be interpreted to update distributions for both tempo and phase, and how these distributions can be combined together in a real-time drum tracking system. Our algorithm is intended for the purposes of synchronisation of pre-recorded audio or video with live drums. We evaluate the algorithm of a new set of drum files from real recordings and compare it to other state-of-the-art algorithms. Our proposed method performs very well, often improving on the results of other real-time beat trackers. The algorithm is implemented in C++ and runs in real-time.

Proceedings of the SMC Conferences, Sep 14, 2014

This paper presents a methodology for predicting the pitch of bass notes by utilising their metri... more This paper presents a methodology for predicting the pitch of bass notes by utilising their metrical position within the bar. Our system assumes two separate audio channels for drums and bass. We make use of onset detection and beat tracking algorithms to determine the onset times for each bass note and the beat locations. A monophonic bass track is analysed for repetitive structures relative to the beat grid, enabling the system to make a prediction of the pitch of each bass note prior to any pitch-related analysis. We present an analysis on a small collection of studio recordings.

This research focuses on real-time gesture learning and recognition. Events arrive in a continuou... more This research focuses on real-time gesture learning and recognition. Events arrive in a continuous stream without explicitly given boundaries. To obtain temporal accuracy, weneed to consider the lag between the detection of an eventand any effects we wish to trigger with it. Two methodsfor real time gesture recognition using a Nintendo Wii controller are presented. The first detects gestures similar to agiven template using either a Euclidean distance or a cosinesimilarity measure. The second method uses novel information theoretic methods to detect and categorize gestures inan unsupervised way. The role of supervision, detection lagand the importance of haptic feedback are discussed.

Off-line beat trackers are often compared to human tappers who provide a ground truth against whi... more Off-line beat trackers are often compared to human tappers who provide a ground truth against which they can be judged. In order to evaluate a real-time beat tracker, we have taken the paradigm of the 'Turing Test' in which an interrogator is asked to distinguish between human and machine. A drummer plays in succession with an interactive accompaniment that has one of three possible tempocontrollers (the beat tracker, a human tapper and a steadytempo metronome). The test is double-blind since the researchers do not know which controller is currently functioning. All participants are asked to rate the accompaniment and to judge which controller they believe was responsible. This method for evaluation enables the controllers to be contrasted in a more quantifiable way than the subjective testimony we have used in the past to evaluate the system. The results of the experiment suggest that the beat tracker and a human tapper are both distinguishable from a steadytempo accompaniment and they are preferable according to the ratings given by the participants. Also, the beat tracker and a human tapper are not sufficiently distinguishable by any of the participants in the experiment, which suggests that the system is comparable in performance to a human tapper.

2012 3rd International Workshop on Cognitive Information Processing (CIP), 2012

We describe an information-theoretic approach to the analysis of music and other sequential data,... more We describe an information-theoretic approach to the analysis of music and other sequential data, which emphasises the predictive aspects of perception, and the dynamic process of forming and modifying expectations about an unfolding stream of data, characterising these using the tools of information theory: entropies, mutual informations, and related quantities. After reviewing the theoretical foundations, we discuss a few emerging areas of application, including musicological analysis, real-time beat-tracking analysis, and the generation of musical materials as a cognitively-informed compositional aid.

International Journal of Human-Computer Studies, 2009

Live music-making using interactive systems is not completely amenable to traditional HCI evaluat... more Live music-making using interactive systems is not completely amenable to traditional HCI evaluation metrics such as taskcompletion rates. In this paper we discuss quantitative and qualitative approaches which provide opportunities to evaluate the music-making interaction, accounting for aspects which cannot be directly measured or expressed numerically, yet which may be important for participants. We present case studies in the application of a qualitative method based on Discourse Analysis, and a quantitative method based on the Turing Test. We compare and contrast these methods with each other, and with other evaluation approaches used in the literature, and discuss factors affecting which evaluation methods are appropriate in a given context.

B-Keeper is a real-time beat-tracker for live performance with drums. The system maintains synchr... more B-Keeper is a real-time beat-tracker for live performance with drums. The system maintains synchronisation between a software sequencer and a drummer by analysing onsets form the kick drum and making small tempo changes. This system enables the sequencing of computer generated parts in time with the drums and provides a structure for real-time analysis for the purpose of integrating computers further into live performance.

We present a method for real-time pitch-tracking which generates an estimation of the relative am... more We present a method for real-time pitch-tracking which generates an estimation of the relative amplitudes of the partials relative to the fundamental for each detected note. We then employ a subtraction method, whereby lower fundamentals in the spectrum are accounted for when looking at higher fundamental notes. By tracking notes which are playing, we look for note off events and continually update our expected partial weightings for each note. The resulting algorithm makes use of these relative partial weightings within its decision process. We have evaluated the system against a data set and compared it with specialised offline pitch-trackers.

We present an overview of developments towards interactive musical systems. A description of an i... more We present an overview of developments towards interactive musical systems. A description of an interactive system is given and we consider potential uses for the automation of creative processes within live performance. We then look at the history of research into the problem of automatic accompaniment, discuss a variety of current interactive systems and present some ideas for future research.

Journal of New Music Research, 2015

This paper presents a Bayesian probabilistic framework for real-time alignment of a recording or ... more This paper presents a Bayesian probabilistic framework for real-time alignment of a recording or score with a live performance using an event-based approach. Multitrack audio files are processed using existing onset detection and harmonic analysis algorithms to create a representation of a musical performance as a sequence of time-stamped events. We propose the use of distributions for the position and relative speed which are sequentially updated in real-time according to Bayes' theorem. We develop the methodology for this approach by describing its application in the case of matching a single MIDI track and then extend this to the case of multitrack recordings. An evaluation is presented that contrasts our multitrack alignment method with state-of-theart alignment techniques.

Proceedings of the International Conference on New Interfaces for Musical Expression, 30 May - 1 June 2011, Oslo, Norway, 2011

This paper introduces the Seaboard, a new tangible musical instrument which aims to provide music... more This paper introduces the Seaboard, a new tangible musical instrument which aims to provide musicians with significant capability to manipulate sound in real-time in a musically intuitive way. It introduces the core design features which make the Seaboard unique, and describes the motivation and rationale behind the design. The fundamental approach to dealing with problems associated with discrete and continuous inputs is summarised

This paper introduces the Seaboard, a new tangible musical instrument which aims to provide music... more This paper introduces the Seaboard, a new tangible musical instrument which aims to provide musicians with signicant capability to manipulate sound in real-time in a musically intuitive way. It introduces the core design features which make the Seaboard unique, and describes the motivation and rationale behind the design. The fundamental approach to dealing with problems associated with discrete and continuous inputs is summarized.

This paper addresses the problem of determining tempo and timing data from a list of beat annotat... more This paper addresses the problem of determining tempo and timing data from a list of beat annotations. Whilst an approximation to the tempo can be calculated from the inter-beat interval, the annotations also include timing variations due to expressively timed events, phase shifts and errors in the annotation times. These deviations tend to propagate into the tempo graph and so tempo analysis methods tend to average over recent inter-beat intervals. However, whilst this minimises the effect such timing deviations have on the local tempo estimate, it also obscures the expressive timing devices used by the performer. Here we propose a more formal method for calculation of the optimal tempo path through use of an appropriate cost function that incorporates tempo change, phase shift and expressive timing.

This paper describes the development of B-Keeper, a reatime beat tracking system implemented in J... more This paper describes the development of B-Keeper, a reatime beat tracking system implemented in Java and Max/MSP, which is capable of maintaining synchronisation between an electronic sequencer and a drummer. This enables musicians to interact with electronic parts which are triggered automatically by the computer from performance information. We describe an implementation which functions with the sequencer Ableton Live.

2012 3rd International Workshop on Cognitive Information Processing (CIP), 2012

We describe an information-theoretic approach to the analysis of music and other sequential data,... more We describe an information-theoretic approach to the analysis of music and other sequential data, which emphasises the predictive aspects of perception, and the dynamic process of forming and modifying expectations about an unfolding stream of data, characterising these using the tools of information theory: entropies, mutual informations, and related quantities. After reviewing the theoretical foundations, we discuss a few emerging areas of application, including musicological analysis, real-time beat-tracking analysis, and the generation of musical materials as a cognitively-informed compositional aid.

Computer Music Journal, 2013

This article presents a method of adjusting the tempo of a music software sequencer so that it re... more This article presents a method of adjusting the tempo of a music software sequencer so that it remains synchronized with a drummer's musical pulse. This allows music sequencer technology to be integrated into a band scenario without the compromise of using click tracks or triggering loops with a fixed tempo. Our design implements real-time mechanisms for both underlying tempo and phase adjustment using adaptable parameters that control its behavior. The aim is to create a system that responds to timing variations in the drummer's playing but is also stable during passages of syncopation and fills. We present an evaluation of the system using a stochastic drum machine that incorporates a level of noise in the underlying tempo and phase of the beat. We measure synchronization error between the output of the system and the underlying pulse of the drum machine and contrast this with other real-time beat trackers. The software, B-Keeper, has been released as a Max for Live device...