Tom Mitchell’s research while affiliated with WWF United Kingdom and other places

Digital audio synthesis has become an important component of modern music production with techniques that can produce realistic simulations of real instruments. Physical modelling sound synthesis is a category of audio synthesis that uses mathematical models to emulate the physical phenomena of acoustic musical instruments including drum membranes, air columns and strings. The synthesis of physical phenomena can be expressed as discrete variants of Newton's laws of motion, using, for example, the Finite-Difference Time-Domain method or FDTD. FDTD is notoriously computationally expensive and the real time demands of sound synthesis in a live setting has led implementers to consider offloading to GPUs. In this paper we present multiple OpenCL implementations of FDTD for real time simulation of a drum membrane. Additionally, we compare against an AVX optimized CPU implementation and an OpenGL version that utilizes a careful mapping to the GPU texture cache. We find using a discrete, laptop class, AMD GPU that for all but the smallest mesh sizes, the OpenCL implementation out performs the others. Although, to our surprise we found that optimizing for work-group local memory provided only a small performance benefit.

Considering the generation of musical tunings, it is reasonable to expect that the many constructs contained in Functional programming languages may provide useful tools for exploring both conventional and new tunings. In this paper we present a number of approaches for manipulating tunings using basic mathematics. While this provides a simple foundation for describing temperament, it is fundamental enough to support a variety of approaches and further, allows the unbounded description of arbitrary tunings. It is expected that this notion will be useful in defining tunings, and by extension scales, for Digital Musical Instruments. This breaks down the physical barrier that has limited the likes of just intonations from having practical applications in the performance setting. It also enables composers to explore a variety of non traditional temperaments rapidly, without having to manually tune each note.

In a New Interface for Musical Expression (NIME), the design of the relationship between a musician’s actions and the instrument’s sound response is critical in creating instruments that facilitate expressive music performance. A growing body of NIMEs expose this design task to the end performer themselves, leading to the possibility of new insights into NIME mapping design: what can be learned from the mapping design strategies of practicing musicians? This research contributes a qualitative study of four highly experienced users of an end-user mapping instrument to examine their mapping practice. The study reveals that the musicians focus on designing simple, robust mappings that minimize errors, embellishing these control gestures with theatrical ancillary gestures that express metaphors. However, musical expression is hindered by the unintentional triggering of musical events. From these findings, a series of heuristics are presented that can be applied in the future development of NIMEs.

Modern gestural interaction and motion capture technology is frequently incorporated into Digital Musical Instruments (DMIs) to enable new methods of musical expression. A major topic of interest in this domain concerns how a performer's actions are linked to the production of sound. Some DMI developers choose to design these mapping strategies themselves, while others expose this design space to performers. This work explores the latter of these scenarios, studying the user-defined mapping strategies of a group of experienced mid-air musicians chosen from a rare community of DMI practitioners. Participants are asked to design mappings for a piece of music to determine what factors influence their choices. The findings reveal novice performers spend little time reviewing mapping choices, more time practising, and design mappings that adhere to musical metaphors. Experienced performers edit mappings continuously and focus on the ergonomics of their mapping designs.

Translating the complex, multi-dimensional data produced by simulations of biomolecules into an intelligible form is a major challenge in computational chemistry and biology. The so-called “free energy landscape” is amongst the most fundamental concepts used by scientists to understand both static and dynamic properties of biomolecular systems. In this paper we use Markov models to design a strategy for mapping features of this landscape to sonic parameters, for use in conjunction with visual display techniques such as structural animations and free energy diagrams. This allows for concurrent visual display of the physical configuration of a biomolecule and auditory display of characteristics of the corresponding free energy landscape. The resulting sonification provides information about the relative free energy features of a given configuration including its stability.

Translating the complex, multi-dimensional data from simulations of biomolecules to intuitive knowledge is a major challenge in computational chemistry and biology. The so-called "free energy landscape" is amongst the most fundamental concepts used by scientists to understand both static and dynamic properties of biomolecular systems. In this paper we use Markov models to design a strategy for mapping features of this landscape to sonic parameters, for use in conjunction with visual display techniques such as structural animations and free energy diagrams.

The need for thorough evaluations is an emerging area of interest and importance in music interaction research. As a large degree of DMI evaluation is concerned with exploring the subjective experience: ergonomics, action-sound map-pings and control intimacy; User Experience (UX) methods are increasingly being utilised to analyse an individual's experience of new musical instruments, from which we can extract meaningful, robust findings and subsequently gen-eralised and useful recommendations. However, many music interaction evaluations remain informal. In this paper, we provide a meta-review of 132 papers from the 2014 – 2016 proceedings of the NIME, SMC and ICMC conferences to collate the aspects of UX research that are already present in music interaction literature, and to highlight methods from UX's widening field of research that have not yet been explored. Our findings show that usability and aesthetics are the primary focus of evaluations in music interaction research , and other important components of the user experience such as enchantment, motivation and frustration are frequently if not always overlooked. We argue that these factors are prime areas for future research in the field and their consideration in design and evaluation could lead to a better understanding of NIMEs and other computer music technology.

This paper presents GestureChords, a mapping strategy for chord selection in freehand gestural instruments. The strategy maps chord variations to a series of hand postures using the concepts of iconicity and conceptual metaphor, influenced by their use in American Sign Language (ASL), to encode meaning in gestural signs. The mapping uses the conceptual metaphors MUSICAL NOTES ARE POINTS IN SPACE and INTERVALS BETWEEN NOTES ARE SPACES BETWEEN POINTS, which are mapped respectively to the number of extended fingers in a performer’s hand and the abduction or adduction between them. The strategy is incorporated into a digital musical instrument and tested in a preliminary study for transparency by both performers and spectators, which gave promising results for the technique.