SMC2011 Papers accepted for poster presentation

Abstract: For the description of rhythmic content of music signals usually features are preferred that are invariant in presence of tempo changes. In this paper it is shown that the importance of tempo depends on the musical context. For popular music, a tempo-sensitive feature is optimized on multiple datasets using analysis of variance, and it is shown that also a tempo-robust description profits from the integration into the resulting processing framework. Important insights are given into optimal parameters for rhythm description, and limitations of current approaches are indicated.

Abstract: Machine listening and machine learning are critical aspects in seeking a heightened musical agency for new interactive music systems. This paper details LL (ListeningLearning), a project which explored a number of novel techniques in this vein. Feature adaptation using histogram equalisation from computer vision provided an alternative normalization scheme. Local performance states were classified by running multiple k-means clusterers in parallel based on statistical summary feature vectors over windows of feature frames. Two simultaneous beat tracking processes detected larger scale periodicity commensurate with bars, and local IOI information, reconciling these. Further, a measure of `free' playing as against metrically precise playing was explored. These various processes mapped through to control a number of live synthesis and processing elements, in a case study combining a human percussionist and machine improvisation system. A further project has subsequently adapted core parts of the work as a Max/MSP external, first used for Sam Hayden's violectra project, and now released in conjunction with disclosure of code for this paper.

Abstract: This paper presented the researches and the developments realized for an artistic project called Luna Park. This work is widely connected, at various levels, in the paradigm of the concatenative synthesis, both to its shape and in the processes which it employs. Thanks to a real-time pro- gramming environment, synthesis engines and prosodic trans- formations are manipulated, controlled and activated by the gesture, via accelerometers realized for the piece. This paper explains the sensors, the real time audio engines and the mapping that connects this two parts. The world pre- miere of Luna Park takes place in Paris, in the space of projection of the IRCAM, on June 10th, 2011, during the festival AGORA.

Abstract: The synchronization of natural and technical periodic processes can be simulated with self-sustained oscillators. Under certain conditions, these oscillators adjust their frequency and their phase to a master oscillator or to other self-sustained oscillators. These processes can be used in sound synthesis for the tuning of non-linear oscillators, for the adjustment of the pitches of other oscillators, for the synchronization of periodic changes of any sound parameters and for the synchronization of rhythms. This paper gives a short introduction to the theory of synchronization, shows how to implement the differential equations which describe the self-sustained oscillators and gives some examples of musical applications. The examples are programmed as mxj~ externals for MaxMSP. The Java code samples are taken from the perform routine of these externals. The externals and Max patches can be downloaded from http://www.icst.net/.

Abstract: A new method for two-dimensional interpolation called Intersecting N-Spheres Interpolation is described.  It is simple to compute and its generalization to higher dimensions is straightforward.  It is presented as a tool used in the design of many-to-many mappings for digital musical instruments.  Examples of its uses, including such mappings in conjunction with a musical interface called the sponge, are given and discussed.

Abstract: This paper discusses the design and implementation of an interactive touch surface exhibit which re-appropriates a historic electroacoustc work for the digital age. The electroacoustic work in question is Henri Pousseur's seminal `Scambi' composition, originally created in 1957 at the RAI Studios, Milan. The status of Scambi as a key example of an electroacoustic `open' form makes it ideal for re-appropriation as an interactive public exhibit, while an existing musicological analysis of Pousseur's compositional instructions for Scambi provide insight for the user interface design and translation of written textual composition process into interactive software. The project is on-going, and this paper presents our current work-in progress. We address the musicological, practical and aesthetic implications of this work, discuss informal observation of users engaging with our tabletop system, and comment on the nature of touchscreen interfaces for musical interaction. This work is therefore relevant to the electroacoustic community, fields of human computer interaction, and researchers developing new interfaces for musical expression. This work contributes to the European Commission funded DREAM project.

Abstract: Distributing short sequences of sounds in space as well as in time is important for many applications, including the signaling of hot spots. In a first experiment, we show that the accuracy in the localization of one such spot is not improved by the apparent motion induced by spatial se- quencing. In a second experiment, we show that increasing the number of emission points does improve the smooth- ness of spatio-temporal trajectories, even for those rapidly- repeating pulses that may induce an auditory-saltation illu- sion. Other indications for auditory-display designers can also be drawn from the experiments.

Abstract: An exploratory experiment was carried out in which subjects with different musical skills were asked to play a digital piano keyboard, first by following a specific key sequence and style of execution, and then performing freely. Judgments of perceived sound quality were recorded in three different settings, including standard use of the digital piano with its own internal loudspeakers, and conversely use of the same keyboard for controlling a physics-based piano sound synthesis model running on a laptop in real time. Through its audio card, the laptop drove a couple of external loudspeakers, and occasionally a couple of shakers screwed to the bottom of the keyboard. The experiment showed that subjects prefer the combination of sonic and vibrotactile feedback provided by the synthesis model when playing the key sequences, whereas they promote the quality of the original instrument when performing free. However springing out of a preliminary evaluation, these results were in good accordance with the development stage of the synthesis software at the time of the experiment. They suggest that vibrotactile feedback modifies, and potentially improves the performer's experience when playing on a digital piano keyboard.

Abstract: Most methods to compute content-based similarity between audio samples are based on descriptors representing the spectral envelope or the texture of the audio signal only. This paper describes an approach based on (i) the extraction of spectro--temporal profiles from audio and (ii) non-linear alignment of the profiles to calculate a distance measure.

Abstract: This paper proposes a sound spazialization control system based on acoustic localization of performers. Our proposal is to allow a performer to plan and conduct the sound spatialization, acting in real-time through the spatial movement of sound source. The proposed system is able to locate and track the sound in two-dimensional space with accuracy, so that the two coordinate values of the real source position can be used to control the position of virtual source in a spatialization setup. We focus our attention on localization and tracking of human voice in real moderate reverberant and noisy environment. We consider a system based on Generalized Cross-Correlation (GCC) and Phase Transform (PHAT) weighting for time delay estimation between signals. Besides, a Kalman filter is applied directly to smooth the time series of observed TDOAs, in order to obtain a more robust and accurate estimate of position. We developed a prototype system, composed by an array of three microphones and a Max/MSP external object for digital localization process, to test the system control in real-world and to validate its usability.

Abstract: AudioArduino is a system consisting of an ALSA (Advanced Linux Sound Architecture) audio driver and corresponding microcontroller code; that can demonstrate full-duplex, mono, 8-bit, 44.1 kHz soundcard behavior on an \FTDI based Arduino. While the basic operation as a soundcard can be demonstrated with nothing more than a pair of headphones and a couple of capacitors - modern PC soundcards typically make use of multiple signal standards; and correspondingly, multiple connectors.
The usual distinction that typical off-the-shelf stereo soundcards make, is between line-level signals (line-in/line-out) - and those not conforming to this standard (such as microphone input/speaker output). To provide a physical illustration of these issues in soundcard design, this project outlines an open design for a simple single-sided PCB, intended for experimentation (via interconnection of basic circuits on board). The contribution of this project is in providing a basic introductory overview of the problems (PWM output in particular) in analog I/O design and implementation for soundcards, through a real world example; which would be useful primarily in an educational scope.

Abstract: One advantage of modern smart phones is their ability torun complex applications such as instrument simulators. Most available percussion applications use a trigger-type implementation to detect when a user has made a gesture corresponding to a drum hit, which limits the expressive-ness of the instrument. This paper presents an alterna-tive method for detecting drum gestures and producing a latency-reduced output sound. Multiple features related to the shape of the percussive stroke are also extracted. These features are used in a variety of physically-inspired and novel sound mappings. The combination of these com- ponents provides an expressive percussion experience for the user.

Abstract: This paper presents first results of an ongoing project devoted to the analysis and virtualization of the analog electronic devices of the “Studio di Fonologia Musicale”, one of the European centres of reference for the production of electroacoustic music in the 1950’s and 1960’s. After a brief summary of the history of the Studio, the paper discusses a particularly representative musical work produced at the Studio, "Scambi" by Henri Pousseur, and it presents initial results on the analysis and simulation of the electronic device used by Pousser in this composition, and the ongoing work finalized at developing an installation that re-creates such electronic lutherie.

Abstract: This paper presents a hardware and software system for adding multiple touch sensitivity to the piano-style keyboard.  The traditional keyboard is a discrete interface, defining notes by onset and release.  By contrast, our system allows continuous gestural control over multiple dimensions of each note by sensing the position and size of up to three touches per key.  Sensors are constructed using system-on-chip capacitive touch sensing controllers on circuit boards shaped to each key.  The boards are laminated with thin plastic sheets to provide a traditional feel to the performer.  The sensors, which are less than 2.5mm thick, mount atop an existing acoustic or electronic piano keyboard.  The hardware connects by USB, and software on a host computer generates OSC messages reflecting a broad array of low- and high-level gestures, including motion of single points, two- and three-finger pinch and slide gestures, and continuous glissando tracking across multiple keys.  This paper describes the sensor design and presents selected musical mappings.

Abstract: Sinusoidal modeling systems are commonly employed in sound and music processing systems for their ability to decompose a signal to its fundamental spectral information. Sinusoidal modeling is a two-phase process: sinusoidal parameters are estimated in each analysis frame in the first phase, and these parameters are chained into sinusoidal trajectories in the second phase. This paper focuses on the first phase. Current methods for estimating parameters rely heavily on the resolution of the Fourier transform and are thus hindered by the Heisenberg uncertainty principle. A novel approach is proposed that can super-resolve frequencies and attain more accurate estimates of sinusoidal parameters than current methods. The proposed algorithm formulates parameter estimation as a linear programming problem, in which the L1 norm of the residual component of the sinusoidal decomposition is minimized. Shared information from iteration to iteration and from frame to frame allows for efficient parameter estimation at high sampling rates.

Abstract: This paper describes a multiobjective approach for melody harmonization in evolutionary music. There are numerous methods and a myriad of results to a process of harmonization of a given melody according to Western standards. Some implicit rules can be extracted from musical theory, but some harmonic aspects can only be defined by preferences of a composer. Thus, a multiobjective approach may be useful to allow an evolutionary process to find a set of solutions that represent a trade-off between the rules in different objective functions. In this paper, a multiobjective evolutionary algorithm defines chord changes with differing degrees of simplicity and dissonance. While presenting such an algorithm, we discuss how to embed musical cognizance in Genetic Algorithms in a meta-level.  Experiments were held and compared to human judgment of the results. The findings suggest that it is possible to devise a fitness function which reflects human intentions for harmonies.

Abstract: This paper presents a novel machine learning algorithm that has been specifically developed for the classification of semiotic musical gestures.  We demonstrate how our algorithm, called the Adaptive Naive Bayes Classifier, can be quickly trained with a small number of training examples and then classify a set of musical gestures in a continuous stream of data that also contains non-gestural data.  The algorithm also features an adaptive function that enables a trained model to slowly adapt itself as a performer refines and modifies their own gestures over, for example, the course of a rehearsal period.  The paper is concluded with a study that shows a significant overall improvement in the classification abilities of the algorithm when the adaptive function is used.

Abstract: There is some evidence that both music preferences and an attraction to computers and technology are related to personality. This paper will argue that the specific measure of ‘music-systemizing’ may therefore be predictive of a preference for electronica, techno and computer-generated music.  We report a preliminary study with 36 participants in which those who enjoy computer music based genres demonstrated a trend of a higher mean score on the music-systemizing scale than those who enjoy love songs.

Abstract: Various attempts at automatic music composition systems have been made but they have not dealt with the issue of how to edit the composed piece by the user. In this paper, we propose a human-in-the-loop music composition system, where the manual editing stage is integrated into the composition process.  This system first generates a musical piece based on the lyrics input by the user. After that, the user can edit the melody and/or chord progression. The feature of this system is to regenerate, once the user edits the melody or chord progression of the generated piece, the remaining part so that it musically matches the edited part. With this feature, users can try various melodies and arrangements without taking into account the musical inconsistency between the melody and chord progression. We confirmed that this feature facilitated the user's trial and error in elaborating music.

Abstract: This paper presents a full-body vibrotactile display that can be used as a tool to help learning music performance. The system is composed of 10 vibrotactile actuators placed on different positions of the body as well as an extended and modified version of a software tool for generating tactile events, the FA/SA application. We carried out initial tests of the system in the context of enhancing the learning process of novice guitar players. In these tests we asked the performers to play the guitar part over a drum and bass-line base track, either heard or felt by the performers through headphones and the tactile display they were wearing. Results show that it is possible to accurately render the representation of the audio track in the tactile channel only, therefore reducing the cognitive load in the auditory channel.

Abstract: Pure and Faust are two functional programming languages useful for programming computer music and other multimedia applications. Faust is a domain-specific language specifically designed for synchronous signal processing, while Pure is a general-purpose language which aims to facilitate symbolic processing of complicated data structures in a variety of application areas. Pure is based on the LLVM compiler framework which supports both static and dynamic compilation and linking.
This paper discusses a new LLVM bitcode interface between Faust and Pure which allows direct linkage of Pure code with Faust programs, as well as inlining of Faust code in Pure scripts. The interface makes it much easier to integrate signal processing components written in Faust with the symbolic processing and metaprogramming capabilities provided by the Pure language. It also opens new possibilities to leverage Pure and its JIT (just-in-time) compiler as an interactive frontend for Faust programming.

Abstract: In film and video production, the selection or production of suitable music often turns out to be an expensive and time-consuming task. Directors or video producers frequently do not possess enough expert musical knowledge to express their musical ideas to a composer, which is why the usage of temp tracks is a widely accepted practice. To improve this situation, we aim at devising a generative music prototyping tool capable of supporting media producers by exposing a set of high-level parameters tailored to the vocabulary of films (such as mood descriptors, semantic parameters, film and music genre etc.). The tool is meant to semi-automate the process of producing and/or selecting temp tracks by using algorithmic composition strategies to either generate new musical material, or process exemplary material, such as audio or MIDI files. Eventually, the tool will be able to provide suitable raw material for composers to start their work. We will also publish parts of the prototype as an open source framework (the RaPScoM framework) to foster further development in this area.

Abstract: This paper is an initial attempt to study the world of sound effects for motion pictures, also known as Foley sounds. Throughout several audio and audio-video tests we have compared both Foley and real sounds originated by an identical action. The main purpose was to evaluate if sound effects are always better than real sounds [1]. Once this aspect is cleared up, the next step will be to understand how Foley effects exaggerate important acoustic features. These are the basis for being able to create a database of expressive sounds, such as audio caricatures, that will be used in different applications of sound design such as advertisement or soundtracks for movies.

Abstract: The overall vision of a piano which can talk, where the piano produces understandable speech playing notes with a robotic piano player has been developed over the last decade. After successfully transcribing recorded ambient sound for piano and ensembles the outcome of this mapping is also used by the composer Peter Ablinger as artwork, which explores the auditory perception in the tradition of artistic phenomenalists\footnote{in the sense of the work done by Alvin Lucier, who himself described him as phenomenalists}. For this vision robotic piano player has been developed to play the result from the transcription of voice recordings by reconstructing the the key features of the analyzed spectrum stream, here the voice, on the piano. This paper is a report on the development, mentioning the different solutions, and discussing these area. The output as artworks will be referenced.

Abstract: A key challenge in the design of Virtual Musical instruments (VMIs) is finding expressive, playable, learnable mappings from gesture to sound that progressively re-ward practice by performers. Designing such mappings can be particularly demanding in the case of non-contact musical instruments, where physical cues can be scarce. Unaided intuition works well for many instrument de-signers, but others may find design and evaluation heuristics useful when creating new VMIs. In this paper we gather existing criteria from the literature to assemble a simple set of design and evaluation heuristics that we dub articulacy. This paper presents a design case study in which an expressive non-contact finger-tracking VMI, Sound Spheres, is designed and evaluated with the sup-port of the articulacy heuristics. The case study explores the extent to which articulacy usefully informs the design of a non-contact VMI, and we reflect on the usefulness or otherwise of heuristic approaches in this context.

Abstract: Polyphonic music is comprised of independent voices sounding synchronously. The task of voice segregation is to assign notes from symbolic representation of a music score to monophonic voices. Human auditory sence can distinguish these voices. Hence, many previous works utilize perceptual principles. Voice segregation can be applied to music information retrieval and automated music transcription of polyphonic music. In this paper, we propose to modify the voice segregation algorithm of contig mapping approach by Chew and Wu. This approach consists of 3 steps; segmentation, segregation, and combining. We present a modification of “combining” step on the assumption that the accuracy of voice segregation depends on whether the segregation manages to correctly identify which voice is resting. Our algorithm prioritize voice combining at segmentation boundaries with increasing voice counts. We tested our voice segregation algorithm on 78 pieces of polyphonic music by J.S.Bach. The results show that our algorithm attained 92.21% of average voice consistency.

Abstract: The Performance Rendering Contest (Rencon) is an annual international competition in which entrants present computer systems they have developed for generating expressive musical performances, which audience members and organizers judge. Recent advances in performance-rendering technology have brought with them the need for a means for researchers in this area to obtain feedback about the abilities of their systems in comparison to those of other researchers. The Rencon contest at SMC2011 (SMC-Rencon) is going to have two different stages of evaluation. In the first stage, the musicality of generated performances and technical quality of systems will be evaluated by expert reviewers using a blind procedure for evaluation. In the second stage, performances generated on site will be openly evaluated by the SMC audience and Internet viewers. The SMC-Rencon Award will be bestowed on the system scoring the highest number of total points (from both stages).

Abstract: This paper compares the use of two different technologies for controlling sound synthesis in real time: the infrared marker-based motion capture system OptiTrack and Xsens MVN, an inertial sensor-based motion capture suit. We present various quantitative comparisons between the data from the two systems and results from an experiment where a musician performed simple musical tasks with the two systems. Both systems are found to have their strengths and weaknesses, which we will present and discuss.

Abstract: Simultaneous handling and synchronisation of data related to music, such as score annotations, MIDI, video, motion descriptors, sensor data, etc. requires special tools due to the diversity of this data. We present a toolbox for recording and playback of complex music-related data. Using the Sound Description Interchange Format as a storage format and the Open Sound Control protocol as a streaming protocol simplifies exchange of data between composers and researchers.

Abstract: In this article some theoretical issues about the foundations of a laptop orchestra will be presented, prompted by the actual involvement in the design of the S. Giorgio Laptop Ensemble in Venice. The main interest is in the development of an eco-systemic kind of communication/interaction between performers. First the main phenomenological features of orchestra and laptop will be reviewed, followed by a summary of the history of laptop orchestras up to now. A coherent system according to the premises will then be developed defining what will be an orchestral player and what will be a conductor and how they will be musically interacting. Technical issues regarding the set-up of the orchestra and the means of communication between the elements of the orchestra will then be approached. The most versatile solution for this last issue (audio communication) has been found exploiting possibilities of Local Area Network communications on ethernet interfaces. Finally the partial results of the research will be summarized.

Abstract: We describe a multimodal system which exploits the use of footwear-based interaction in virtual environments. We developed a pair of shoes enhanced with pressure sensors, actuators, and markers. Such shoes control a multichannel surround sound system and drive a physically based sound synthesis engine which simulates the act of walking on different surfaces. We present the system in all its components, and explain its ability to simulate natural interactive walking in virtual environments. The system was used in an experiment whose goal was to assess the ability of subjects to walk blindfolded on a virtual plank. Results show that subjects perform the task slightly better when they are exposed to haptic feedback as opposed to auditory feedback, although no significant differences are measured. The combination of auditory and haptic feedback does not significantly enhances the task performance.

Abstract: Technical ear training aims to improve the listening of musicians and sound engineers so that they can technically modify and edit the structure of sound to fully express their artistic intent. In order to provide this technical ear training to non-professionals such as artists, entry-level sound engineers, and music students, the authors have developed a simplified yet personalized ear- raining program. The most distinct feature of this system is to adaptively control the training task based on the trainee’s prior performances. In detail, this system estimates the weakness of the trainee, and generates a training routine which drills focusing on the weakness, so that trainee can effectively practice technical ear training without an instructor. Subsequently, we have investigated the effect of the new training program with one-month long training experiment for eight subjects. The result showed that the group assigned to the proposed training system showed better score improvement than the group assigned to the conventional one.

Abstract: This paper presents a simple model for the extraction of a sound localization cue utilizing pitch cues in the auditory system. In particular, the extraction of the interaural time difference (ITD) as the azimuth localization cue, rather than the interaural intensity difference (IID), is constructed using a conventional signal processing scheme. The new configuration in this model is motivated by psychoacoustical and physiological findings, suggesting that the ITD can be controlled by the pitch cue in the simultaneous grouping of auditory cues. The localization cues are extracted at the superior olivary complex (SOC) while the pitch cue may be extracted at a higher stage of the auditory pathway. To explore this idea in the extraction of ITD, a system is introduced to feed back information on the pitch cue to control and/or modify the ITD for each frequency channel.

Abstract: When learning an instrument, students often like to emulate the sound and style of their favourite performers. The learning process takes many years of study and practice. In the case of synthesisers the vast parameter space involved can be daunting and unintuitive to the novice making it hard to define their desired sound and difficult to understand how it was achieved. Previous research has produced methods for automatically determining an appropriate parameter set to produce a desired sound but this can still require many parameters and does not explain or demonstrate the effect of particular parameters on the resulting sound. As a first step to solving this problem, this paper presents a new approach to searching the synthesiser parameter space to find a sound, reformulating it as a multi-objective optimisation problem (MOOP) where two competing objectives (closeness of perceived sonic match and number of parameters) are considered. As a proof-of-concept a pareto-optimal search algorithm (NSGA-II) is applied to CSound patches of varying complexity to generate a pareto-front of non-dominating (i.e. ”equally good”) solutions. The results offer insight into the extent to which the size and nature of parameter sets can be reduced whilst still retaining an acceptable degree of perceived sonic match between target and candidate sound.

Abstract: Research on analysis of expressive music performance is recently moving from a scenario where the focus is on the single player to a scenario where small music ensembles are investigated and the analysis is extended to the social interaction between the members of the ensemble. A step in this direction is the definition and the validation of a set of score-independent audio features that, on the one hand, can suitably characterize the expressive performance of each instrument in the ensemble and, on the other hand, enable to distinguish among different performances played by the ensemble in different social conditions. This paper focuses on the analysis of four different performances of a same music piece performed by a string quartet. The performances differ both with respect to expressiveness and with respect to factors affecting the social interaction within the ensemble, with a particular focus on the functional roles of the players. The analysis aims at evaluating whether and how much a set of consolidated score-independent audio features, particularly suitable for string instruments, enable to distinguish among such different performances and among the instruments composing the ensemble.

Abstract: This paper provides an overview of a multi-media composition, Leech, which aurally and visually renders BitTor- rent traffic. The nature and usage of BitTorrent networking is discussed, including the implications of widespread music piracy. The traditional usage of borrowed musical material as a compositional resource is discussed and expanded upon by including the actual procurement of the musical material as part of the performance of the piece. The technology and tools required to produce this work, and the roles that they serve, are presented. Eight distinct streams of data are targeted for visualization and sonification: Torrent progress, download/upload rate, file name/size, number of peers, peer download progress, peer location, packet transfer detection, and the music being pirated. An overview of the methods used for sonifying and and visualizing this data in an artistic manner is presented.

Abstract: We propose an approach for the automatic creation of mood playlists in the Thayer plane (TP). Music emotion recognition is tackled as a regression  and classification problem, aiming to predict the arousal and valence (AV) values of each song in the TP, based on Yang’s dataset. To this end, a high number of audio features are extracted using three frameworks: PsySound, MIR Toolbox and Marsyas. The extracted features and Yang’s annotated AV values are used to train several Support Vector Re- gressors, each employing different feature sets. The best performance, in terms of R2 statistics, was attained after forward feature selection, reaching  63%  for arousal and 35.6% for valence. Based on the predicted location of each song in the TP, mood playlists can be created by specifying a point in the plane, from which the closest songs are retrieved. Using one seed song, the accuracy of the created playlists was 62.3% for 20-song playlists, 24.8% for 5-song playlists and 6.2% for the top song.

Abstract: This paper presents a new digital musical instrument that focuses on the issue of feedback in instrument design as a key condition to achieve a performance tool that is both highly responsive and highly expressive. The Sonik Spring emphasizes the relationship between kinesthetic feedback and sound production while at the same time linking visual and gestural motion to the auditory experience and musical outcome. The interface consists of a 15-inch coil that is held and controlled using both hands. The coil exhibits unique stiffness and flexibility characteristics that allow many degrees of variation of its shape and length. The design of the instrument is described and its unique features discussed. Three distinct performance modes are also detailed highlighting the instrument’s expressive potential and wide range functionality.

Abstract: Many traditional and new musical instruments make use of an isomorphic note layout across a uniform planar tessellation.  Recently, a number of hexagonal isomorphic keyboards have become available commercially. Each such keyboard or interface uses a single specific layout for notes, with specific justifications as to why this or that layout is better.  This paper is an exploration of all possible note layouts on isomorphic tessellations.  We begin with an investigation and proof of isomorphism in the two regular planar tessellations (Square and hexagonal), we describe the history and current practice of isomorphic note layouts from traditional stringed instruments to commercial hex keyboards and virtual keyboards available on tablet computers, and we investigate the complete space of such layouts, evaluating the existing popular layouts and proposing a set of new layouts which are optimized for specific musical tasks.

Abstract: This paper introduces a technique to improve the efficiency of the Open Sound Control (OSC) communication protocol. The improvement is achieved by decoupling the user interface and transmission layers of the protocol, thereby reducing the size of the transmitted data and simplifying the parsing process of the receiving end point. The proposed method is related to an internet-based name resolution scheme, and is fully compatible with the current OSC v1.1 specification. Three widely used OSC libraries are modified so that existing applications are able to gain benefits of the improvement with minimal reimplementation effort. The practical applicability of the method is demonstrated with a multitouch-controlled audiovisual application setup. It was found that the required adjustments for the existing OSC libraries and applications are minor, and that the intuitiveness of the OSC user interface layer is retained even if communicating in a more efficient manner.

Abstract: When developing and setting software instruments, the way data from the gesture interfaces are correlated with the parameters required to control the synthesis, i.e. the mapping, has a decisive role in ergonomics, playability and expressiveness of a device. The authors propose an approach based on a modular software design. In order to improve and enrich the interaction between the musician and his/her instrument, the authors propose to introduce the notion of "Dynamic Intermediate Models" (DIM) designed in a modular software architecture to complete and extend the notion of mapping functions. In such a scheme, these modules are inserted between those dedicated to the formatting of data from interfaces and those in charge of audio-graphic synthesis and rendering. In this paper, the general framework of the software architecture and the concept of "Dynamic Intermediate Models" will be presented and developed, based on a theoretical program to implement the DIMs based on a multidisciplinary approach taking into account the different aspects of evaluation.

Abstract: The current paper concerns a work in progress research and design project regarding a forth-coming mixed media interactive performance, which integrates space design, sound, visuals and snowboarding. The aim is to create a play-ful and even provocative experience to the users- performers and to the spectators of the final event by mixing and blending music, sound design, architecture, visual projections and freestyle snowboarding. It is a collaborative effort between a French freestyle snowpark de-velopment and snowboarding events company named H05, and three researchers and practitio-ners in computer music, architectural design and electronic engineering. Computer motion tracking techniques, a variety of spatial and body sensors and sonic transformations of pre-composed material have been and are currently explored for the realization of the musical part of the piece. The fundamental and key concept is to associate sound features and interactively composed sound objects to snowboarding full body gestures. Architectural design plays a critical role in the project, since the composed space shapes the snowboarding movements, which accordingly form the musical and visual elements of our work. The current paper de-scribes our initial designs and working proto-types used during a test period in the HO5 snowparks in the Alps.

Abstract: 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 combine together to give a real-time drum tracking system. The proposed system 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. We discuss the merits of such a formulation and how it makes explicit the assumptions that underlie approaches to beat tracking. We conclude by considering how such an approach might be used for other tasks, such as score following or audio alignment. The proposed algorithm is implemented in C++ and runs in real-time.

Abstract: We present the initial research into a generative electronica system based upon analysis of a corpus, describing the combination of expert human analysis and machine analysis that provides parameter data for generative algorithms. Algorithms in MaxMSP and Jitter for the transcription of beat patterns and section labels are presented, and compared with human analysis. Initial beat generation using a genetic algorithm utilizing a neural net trained on the machine analysis data is discussed, and compared with the use of a probabilistic model.

Abstract: In this paper we outline the Closure-based Cueing Model (CbCM), an algorithm for learning hierarchical musical structure from symbolic inputs. Inspired by perceptual and cognitive notions of grouping, cueing, and chunking, the model represents the schematic and invariant properties of musical patterns, in addition to learning explicit musical representations. Because the learned structure encodes the formal relationships between hierarchically related musi- cal segments, as well as the within-segment transitions, it can be used for the generation of new musical material fol- lowing principles of recombinance. The model is applied to learning melodic sequences, and is shown to general- ize perceptual contour and invariance. We outline a few methods for generation from the CbCM, and demonstrate a particular method for generating ranked lists of plausible continuations from a given musical context.

Abstract: Selecting a sensor technology for a Digital Musical Instrument (DMI) is not obvious specially because it involves a performance context. For this reason, when designing a new DMI, one should be aware of the advantages and drawback of each sensor technology and methodology. In this article, we present a discussion about the Rulers, a DMI based on seven cantilever beams fixed at one end which can be bent, vibrated, or plucked. The instrument has already two sensing versions: one based on IR sensor, another on Hall sensor. We introduce strain gages as a third option for the Rulers, sensor that are widely used in industry for measuring loads and vibration. Our goal was to compare the three sensor technologies according to their measurement function, linearity, resolution, sensitivity and hysteresis and also according to real-time application indicators as: mechanical robustness, stage light sensitivity and temperature sensitivity. Results indicate that while strain gages offer more robust and medium sensitivity solution, the requirements for their use can be an obstacle for novice designers.

Abstract: This paper describes the development of a social game, BeatLED, using music, movement and luminescent textile.The game is based on a tool used in research on synchronization of movement and music, and social entrainment at the Institute of Psychoacoustics and Electronic Music (IPEM) at Ghent University. Players, divided into several teams, synchronize to music and receive a score in realtime, depending on how well they synchronize with the music and each other. While this paper concentrates on the game design and dynamics, an appropriate and original means of providing output to the end users was needed. To accommodate this output, a flexible, stretchable LED-display was developed at CMST (Ghent University), and embedded into textile. In this paper we analyze the characteristics a musical social game should have, as well as the overall merit of such a game. We discuss the various technologies involved, the game design and dynamics, a proof-of-concept implementation and the most prominent test results. We conclude that a real-world implementation of this game not only is feasible, but would also have several applications in multiple sectors, such as musicology research, team-building and health care.