Thomas Lysaght

The generation of natural-synthetic spectra by means of adaptive frequency modulation

Frequency-modulation (FM) synthesis is widely known as a computationally efficient method for synthesizing musically interesting timbres. However, it has suffered from neglect owing to the difficulty in creating natural-sounding spectra and mapping gestural input to synthesis parameters. Recently, a revival has occurred with the advent of adaptive audio-processing methods, and this work proposes a technique called adaptive FM synthesis. This article derives two novel ways by which an arbitrary input signal can be used to modulate a carrier. We show how phase modulation (PM) can be achieved first by using delay lines and then by heterodyning. By applying these techniques to real-world signals, it is possible to generate transitions between natural-sounding and synthesizerlike sounds. Examples are provided of the spectral consequences of adaptive FM synthesis using inputs of various acoustic instruments and a voice. An assessment of the timbral quality of synthesized sounds demonstrates its effectiveness.

Analysis of Sign Language Gestures Using Size Functions and Principal Component Analysis

This paper presents a computer vision based virtual learning environment for teaching communicative hand gestures used in Sign Language. A virtual learning environment was developed to demonstrate signs to the user. The system then gives real time feedback to the user on their performance of the demonstrated sign. Gesture features are extracted from a standard web-cam video stream and shape and trajectory matching techniques are applied to these features to determine the feedback given to the user.

mytune: webvisualization technologies for irish traditional music archives

Online digital music libraries have become important repositories for music for all enthusiasts of Irish traditional music. These libraries have certainly facilitated the discovery of new material and enabled extensive exploration of musical variations on well-known favorites. Current web interfaces to these repositories, offer a combination of text and notation-based information as well as providing audio and midi listening formats. However, these interfaces could take advantage of more recently available technologies offering graph-based, interactive, visual displays and more useful data analytic content. Drawing on the state-of the-art data visualization web libraries, the objective of this work is to present a prototype of a new digital library for Irish traditional music. The design and architecture is detailed using standard Unified Modelling Language (UML) notation. Evaluation is carried out by a usability survey to determine the effectiveness of the enhancements.